And the Cyclone-4 missiles of Ukrainian production. The article discusses the strategy for launching a carrier rocket from an aircraft and provides the necessary calculations and graphs.
The relevance of the article lies in the proposed form of launching a carrier rocket from an aircraft, which provides for a combination of two different approaches to launch a carrier rocket from an aircraft. For the first part of its trajectory, the rocket flies like an aircraft. The rocket overcomes the second part of the trajectory with the help of a braking parachute and thanks to it it is brought to the position required for launch.
The research used the method of constructing a mathematical model in the Delphi-7 programming environment in Pascal. The author has constructed the first mathematical model of the flight of a launch vehicle with a wing after its separation from the aircraft. The second mathematical model was created to describe the flight of the carrier rocket after firing off the bearing surfaces and braking with a turn to the required position for the subsequent launch.
Key words: air launch, launch vehicle, mathematical model, bearing surfaces, braking parachute, oval wing, aircraft.
The history of world aviation is closely related to our country. Back in 1910 of the last century, engineer Alexander Kudashev in Kiev built the first aircraft capable of actually performing a controlled flight (when the pilot controls the aircraft using the steering wheel).
Also in Kiev, the world famous Igor Ivanovich Sikorsky began his aviation career. No less famous Oleg Konstantinovich Antonov, who created the world's largest transport aircraft An-124 and An-225, which are known far beyond the borders of the USSR, also worked for many years in Ukraine and created the most developed and modern aviation-scientific technical complex, which bears his name - the State Enterprise named after O.K. Antonov.
Our country is also a space power, because in our country there are such giants of the space industry as the Yuzhnoye and Yuzhmash design bureaus, which are engaged not only in the production of launch vehicles and satellites, but also produce them at a serial plant. It is thanks to such enterprises that Ukraine participates in many international projects, such as the project of a new type of engines "Vega" (under the auspices of the European Space Agency), "Sea launch" (launching a launch vehicle from an offshore platform in the Pacific Ocean), where the Ukrainian Zenit rocket - 3SL is used as the main carrier of satellites, processing of Dnepr intercontinental ballistic missiles for launching small satellites; the Cyclone-4 project together with the Brazilian space agency for launches from the Alcantara cosmodrome and many other projects.
This article suggests new project called "Air Launch". The project provides for the launch of a Cyclone-4 launch vehicle from an An - 225 Mriya aircraft.
The economic component of the project
The very idea of launching a booster rocket from an aircraft is not new, because even in the times of the twentieth century in countries such as the Soviet Union and the United States of America, scientists developed projects based on various aircraft, but through numerous risk factors, none of the projects was implemented. However, the idea of building a mobile spaceport was implemented in international project Sea Launch. This is a converted offshore oil production platform, which is located in the neutral waters of the Pacific Ocean and has the ability to move in order to be as close to the equator as possible during the launch of the launch vehicle, because each degree of deviation from the equator leads to an increase in speed by 100 m / s , which negatively affects the energy capabilities of the launch vehicle.
Thanks to such transportation of the launch vehicle, the savings in launching the launch vehicle from the aircraft are approximately $ 2-2.5 million.
Launch strategy
Air launch is a method of launching missiles or aircraft from a height of several kilometers, where the launch vehicle is delivered. The delivery vehicle is most often another aircraft, but a balloon or airship can also be used.
From the Air Launch, the Air Launch into Orbit should be highlighted. Air launch into orbit is a method of launching launch vehicles and / or spaceships high in the air from horizontal take-off jet aircraft, both subsonic and supersonic. When this method is used for launching into orbit, it has tremendous advantages over traditional vertical launching of rockets, including due to the reduced mass, reaction force and cost of the rocket.
On the ground, a booster rocket with attached load-bearing surfaces is loaded onto the aircraft using a special lifting mechanism (similar in design with a lifting platform for the Buran orbital ship, which was used to lift the load (Buran) to a height of 25 meters, lowering it using cranes to the height required for loading and connecting the ship to the aircraft). Circuits of such devices exist, which makes it easier to bring this development to life.
After these operations, the aircraft takes off and goes to the launch area. At the border of the launch area, the aircraft must climb 10,000 m and reach the required (design) speed (860 km / h). When such flight indicators are achieved, the aircraft switches to the automatic control system, and is brought to a pitch angle of 10 degrees. At this moment, the automatic system releases the locks holding the launch vehicle on the aircraft. The next step will be the departure of the booster and the maneuvering of the aircraft. The aircraft performs a descent evasive maneuver and the launch vehicle performs a slide maneuver. The booster maneuver is described below. It is necessary to refer to the maneuvering of the aircraft, after firing the rocket, the aircraft begins to decelerate and descend with a simultaneous roll to the side (the left or right side of the roll depends on the direction of the wind at the moment the launch vehicle is fired from the aircraft). After reaching the maximum altitude of the maneuver, the rocket begins to descend and accelerate. The plane leaving the trajectory of the rocket returns to the airfield. The rocket with the help of controls (ailerons, elevators, rudder) stabilizes and adheres to a given trajectory. After reaching the height, when the rocket has a small pitch angle (according to the calculation - 9360m), the bearing surfaces are shot and the braking parachute is released. After opening the braking parachute, the carrier rocket speed continues to decrease and the rocket turns with its output to a vertical position relative to the center of gravity. After performing such actions, the booster launches the main engines of the first stage, fires off the braking parachute and starts the flight in the normal mode.
Similar designs and strategies air launch
The author considered only analogs that launched rockets with a mass of at least 15 tons, because it is these carrier rockets that have the necessary energy characteristics for commercial use. In the 1960s and later in the United States, such experimental rocket planes launched from carrier aircraft were created, including the first hypersonic aircraft - the suborbital manned spaceplane North American X-15, also Bell X -1, Lockheed D - 21 Boeing X - 43, etc. Similar (but not suborbital) systems were also in France (Leduc) and other countries. The air launch was used to test the Enterprise spaceplane in a large-scale program of the Space Shuttle reusable transport system. The first of the detailed air-launched AKS projects was the unrealized Spiral system of the 1960s - 1970s from a hypersonic aircraft - Accelerators, launch vehicles and an orbital aircraft. Air launch was used for flights of a subsonic aircraft, an analogue of its orbital aircraft.
American projects: in the United States, the system has long been implemented by Pegasus (RN) / L-1011 (aircraft). Developed by Orbital Sciences Corporation. The launch is carried out using an L-1011 aircraft from the Lockheed Corporation, specially equipped for this. The separation of the rocket from the carrier aircraft occurs at an altitude of 12 km. The mass of the carrier - 18500 kg (Pegasus), 23130 kg (Pegasus XL) The mass of the payload launched into low-earth orbit by the carrier Pegasus is up to 443 kg. Launch cost (as of 1994) - US $ 11 million. From 1990 to 2008, a total of 40 launches of the Pegasus carrier were carried out with in-orbit artificial satellites, of which 3 launches were unsuccessful. Another system is being developed and there are other AKC projects.
Lockheed-1011 aircraft and Pegasus launch vehicle
Russian - Ukrainian projects: in Russia, the detailed projects AKS BAKS and Air Launch were proposed. In the first project, a spaceplane with an external fuel is launched from the board of the An - 225 (325) "Dream" super heavy aircraft. The main element of the second project is a specially converted heavy aircraft An - 124-100Vse "Ruslan", from the side of which at an altitude of about 10 km, developed by the State Missile Center "Design Bureau im. Makeev "technology, the so-called" mortar "launch of the carrier rocket is carried out, which delivers a payload to the calculated orbit. There are also projects "Burlak" and others, in which a launch vehicle with an artificial satellite is launched from various carrier aircraft Tu-160, An-124, Tu-22M.
Ukrainian projects: in Ukraine, using the An-225 carrier aircraft, the projects of the AKS Svityaz (LV Zenit) AKRK Orel and Lybid (winged spaceplane) have been developed. The An-225-100 carrier aircraft is being developed by the Oleg Antonov ASTC and is a modification of the An-225 Mriya base aircraft. The aircraft is equipped with special equipment for attaching the launch vehicle over the fuselage; inside the sealed cabins, the onboard launch equipment and the operators necessary for launching the launch vehicle are located. The Svityaz launch vehicle is created on the basis of units, assemblies and systems of the Zenit launch vehicle. It is built according to a three-stage scheme. Uses non-toxic fuel components - liquid oxygen and kerosene. When launching spacecraft into geostationary orbit, the launch vehicle is equipped with a solid-propellant apogee degree.
AKRC "Orel" is a two-stage aerospace complex. The first stage of such a complex will be a carrier aircraft developed by the Kiev Aviation Scientific and Technical Complex named after V.I. O. K. Antonova An - 124 ("Ruslan"). The second stage will be a payload carrier rocket developed by the Dnepropetrovsk design bureau Yuzhnoye, which is to be launched from the fuselage of the carrier aircraft.
At the first stages of the creation of the Ukrainian AKRC "Orel" there will be a disposable spacecraft. In the future, multiple spacecraft will also be sent into space and returned to Earth. Unlike the Shuttle and Buran, the launch of the carrier rocket will be carried out not from the external suspension of the carrier aircraft, but from its middle, that is, from the fuselage. There have not yet been such scientific and technical solutions in the world. Such a scheme for launching a payload into a near-earth orbit has a number of undeniable advantages. This is an improved aerodynamic design of the AKRK as a whole, a higher safety of the second stage separation in the form of a booster rocket, more optimal technical and economic indicators, a higher secrecy of the AKRK's dual-use tasks (both purely scientific and commercial, and special, for military purposes) ...
Kazakh - Russian project: Kazakhstan proposes the AKS Ishim project (MiG -31 + RN). AKS projects with air launch of spaceplanes were created in Germany (Zenger-2), Japan (ASSTS), China (prototype Shenlong and AKS of the next generation), etc. Private suborbital spaceplanes SpaceShipOne, SpaceShipTwo, M-55 are launched with the help of air launch. and other similar projects. An air launch from a balloon of a suborbital manned rocket is envisaged in the Stabilo ARCASPACE project of Romania.
The main competitor of the launch strategy proposed in the work is the Russian one, using the An - 124-100Vse aircraft, because the American analogue has a 10 times lower payload weight. The main factor that does not allow the implementation and commercial use of the Russian launch strategy is the gap in the "mortar" shooting of a rocket from an aircraft. Now Russian specialists are working to eliminate this problem. The first launches are scheduled for 2015.
Placement of the launch vehicle on the An-124 Ruslan aircraft.
An - 225 "Mriya" heavy universal transport aircraft
The development of an aircraft designed to move large-sized elements of space systems (including the VKS Energia-Buran) began in 1985. The first flight of the An-225, built at the Kiev aircraft plant, took place on December 21, 1988, and on May 13, 1989, the An-225 had already transported the Buran from Zhukovsky to the Baikonur cosmodrome. 106 world records were set on this aircraft.
Aircraft structure
Fuselage. It has two decks: above is the crew cabin and the cabin of the accompanying personnel, utility rooms (kitchen, cloakroom, toilet), below is the cargo compartment. It can accommodate loads weighing up to 250 tons. To ensure loading and unloading, a front cargo hatch and a ramp are used.
Wing. The wing is made of long (up to 30 meters) pressed panels. The panels are interconnected by titanium fasteners, providing tightness and a high level of resistance.
Plumage of the aircraft. Two-keel. The stabilizer has a span of 30 meters, has a caisson, is made of extruded panels and rolled plates of aluminum alloys. The elevator has six sections, three on each console. Elevator - from two sections on each keel.
Chassis. Consists of a two-post front and fourteen-post main landing gear. All Struts have a split release capability to avoid landing without extending the landing gear. Also on the chassis is a weight and centering control system. The brakes are carbon.
Engines. D-18T engines are installed on the An-225 aircraft (starting thrust of one engine is 23.06 tons). The engine is a three-shaft turbofan with a fuel consumption of 0.57 kg of thrust per year in cruising mode.
Systems. All aircraft systems are highly automated and require minimal crew attention during flight. Their performance is supported by 34 on-board computers. The flight-navigation and radio-technical complexes ensure the control of the aircraft in automatic and manual modes at all stages of the flight, as well as the processing and delivery of all necessary flight and navigation information to the aircraft on-board systems and to the light indicators in the cockpit. The control system includes an electro-hydraulic helm control system with four-fold redundancy and a fly-by-wire control system for wing mechanization with double redundancy. The hydraulic complex consists of four main and two backup hydraulic systems that ensure the operation of the steering surfaces, wing mechanization, raising and lowering the landing gear, opening and closing hatches and doors.
The idea of launching a spacecraft from an air carrier is regularly proposed as a way to radically facilitate human access to space. However, only one launch vehicle uses this principle. About what is beneficial and what difficulties an air launch creates, this post.
A bit of history
Rocket aircraft
Air launch was very successfully used in the United States after the war for the study of flight to high speeds and heights. Bell X-1, on which the speed of sound was overcome for the first time in the world, was launched from a suspension on a B-29 bomber:
The decision was very logical - the use of rocket engines meant a small supply of fuel, which would not be enough for a full-fledged launch from the ground. The X-1 model was developed - the X-1A crossed the border in Mach two and studied the behavior of the aircraft at high altitudes (up to 27 km). Modifications X-1B, C, D, E were used for further research.
The next big step forward was the X-15 rocket plane. It also took off from an airborne carrier - a B-52 bomber:
The powerful engine developed a thrust of 250 kilonewtons (71% of the thrust of the Redstone rocket engine), could reach a speed of 7000 km / h and an altitude of 80 km. It would seem that the United States has two roads to space - fast and dirty on Mercury capsules, Redstone and Atlas rockets, and longer, but much more beautiful, on X-15, X-20 and subsequent projects. However, the "airplane" program was in the shadow of space flights, and, despite the successfully achieved goals, did not receive such brilliant development as the "Mercury" - "Gemini" - "Apollo" line.
Neil Armstrong. He flew the X-15, but left the project on time.
Ballistic missiles
An alternative approach was the development of air-launched ballistic missiles. In the late fifties, when ballistic missiles required several hours to prepare for launch, they were inferior to strategic bombers in flexibility and reaction time on alert. The bombers could patrol the borders of the enemy country for hours, and, after command, they could strike within tens of minutes, or they could also be quickly withdrawn. And ballistic missiles had the critical advantage of inability to intercept. The idea arose of combining the merits of the two systems - the development of a ballistic missile for a strategic bomber. This is how the GAM-87 Skybolt project was born:
The first test launches began in 1961, with the first fully successful launch on December 19, 1962. However, by this time, the Navy was receiving ballistic missiles for submarines Polaris, which could "patrol" under water for months. The United States Air Force was developing the Minuteman solid-propellant rocket, which was comparable to the Skybolt, but the rocket was in the silo, ready to be fired, which was much more convenient. The project was closed.
On October 24, 1974, the Minuteman III rocket was dropped from the cargo compartment of the C-5 transporter as an experiment:
The test was successful, but the military saw no need for such a system, and the project was canceled. In the USSR, there was one notable project, but extremely interesting:
The system of a hypersonic booster aircraft and an orbital aircraft was supposed to start from the runway, gain altitude up to 30 km and speed up to 6M (6700 km / h). Then the orbital plane, together with the booster stage on a fluorine / hydrogen fuel pair, was disconnected and accelerated independently until it entered orbit. The project was started in 1964 and officially closed in 1969 (although the orbital plane was "clandestinely" tested as a test of the future Buran technologies). The saddest thing (why - more on that below) is that the booster plane was not built and tested.
I recommend it on the Buran.ru website.
Modernity
Currently, there is one air launch vehicle, two completed projects of suborbital air launch aircraft and models for testing hypersonic engines. Let's consider them in more detail:PH Pegasus
The first launch - 1990, 42 launches in total, 3 failures, 2 partial successes (orbit slightly below the required one), 443 kg into low orbit. A modified L-1011 passenger aircraft is used as an air carrier. Separation from the carrier is carried out at an altitude of 12 kilometers and a speed not exceeding 0.95M (1000 km / h).
SpaceShipOne
Suborbital air launch aircraft. It was developed for participation in the Ansari X-Prize competition, made 17 flights in 2003-2004, of which the last three were suborbital space flights up to an altitude of about 100 km. Despite the optimistic promises "In the next 5 years about 3,000 people will be able to fly into space" the project was effectively halted after winning the X-Prize, and for ten years no space tourists have flown suborbital trajectories.
SpaceShipTwo
Suborbital air launch aircraft. It has been under development for ten years to replace SpaceShipOne. Test flights are currently underway, the maximum altitude reached as of February 2014 is 23 km.
X-43, X-51
Unmanned vehicles for testing hypersonic engines.
The X-43 was originally designed as a scale model of the future X-30 spaceplane. Made three flights. The first in June 2001 ended in failure due to errors in calculations, which led to the loss of stabilization of the booster stage. The second, in March 2004, was successful, reaching a speed of 6.83M. The third flight took place in November 2004, the speed of 9.6M was reached in 12 seconds.
The X-51 was designed for slower (~ 5M) but longer flights. Made four flights - a relatively successful first in May 2010 (200 out of the planned 300 seconds at 5M), two unsuccessful ones, and completely successful (210 seconds at 5M, as planned) in May 2013.
Unrealized projects
There are also unrealized projects: MAKS, HOTOL, Burlak, Vehra, AKS Tupolev-Antonov, Polet, Stratolaunch,.Calculations of the profitability of an air launch
The Pegasus launch vehicle gives us a very convenient opportunity to determine the degree of profitability of an air launch. The fact is that the Minotaur I launch vehicle has the second and third stage of the Pegasus as the third and fourth stages, it outputs the same payload, but starts from the ground. The comparison of masses seems to be noticeable in favor of "Pegasus" - an air launch rocket weighs 23 tons, and a ground one - 36 tons. However, in order to fully compare these launch vehicles, it is necessary to calculate the characteristic velocity margin, which is given by the rocket stages. On the material of the Encyclopedia Astronautica (data for Pegasus-XL, data for Minotaur I), the reserves of the characteristic speed of the steps were calculated for the same payload:
Calculated document in Google Docs
The result turned out to be very curious - due to the air launch, 12.6 percent of the characteristic speed is saved. On the one hand, this is a rather noticeable benefit. On the other hand, this is not too much to cause an explosive growth in air launch systems.
Note the hypothetical comparison with the Spiral. If "Pegasus" was on the "Spiral" booster aircraft, the separation would take place at a speed of ~ 1800 m / s and an altitude of 30 km, which would save at least 2000 m / s in characteristic speed. By the same principle, there is a comparison with the "Minotaur". Notice how much the benefit has increased. Hence it follows that the benefit of an air launch is determined to the greatest extent by the carrier - the higher the speed and separation height, the higher the benefit.
General considerations about the advantages and disadvantages of an air launch
Advantages
Reducing gravity losses... The higher the initial velocity, the smaller the initial pitch angle of the rocket. Gravitational losses are calculated as an integral of the pitch angle function, therefore, the smaller the pitch to the horizon, the smaller the losses.
Model plot of the pitch angle. Curvilinear trapezoid area (shaded in red) - gravitational losses.
Reduced drag losses... The pressure decreases exponentially with height: 
At an altitude of 12 km, where the Pegasus starts, the pressure is about 5 times less than at sea level (~ 200 millibars). At an altitude of 30 km, it is already a hundred times less (~ 10 millibars).
Reduced back pressure losses... The rocket engine works more efficiently in a vacuum, where there is no external pressure to prevent the expansion and projection of fuel. The ID of one engine on the surface is less than in vacuum, therefore starting in a rarefied atmosphere will reduce back pressure losses.
Jet engine has a higher specific impulse... Since the oxidizer is taken "free" from the ambient air, it does not need to be carried with you, which increases the specific impulse of the system due to the carrier aircraft.
Ability to use existing infrastructure... The air launch system can use existing airfields without the need for launch facilities. But the pre-launch preparation systems (assembly and testing complex, fuel component warehouses, flight control buildings) still need to be built.
The ability to start from the desired latitude... If the carrier aircraft has a significant range, you can start from a lower latitude to increase the payload, or shift to the desired latitude to create the desired orbital inclination.
disadvantages
Very poor scalability... The rocket, which delivers 443 kg to LEO, weighs a comfortable 23 tons, which can be attached / suspended / put on an aircraft without any problems. However, rockets that put at least 2 tons into orbit begin to weigh 100-200 tons, which is close to the carrying capacity of existing aircraft: An-124 lifts 120 tons, An-225 - 247 tons, but it is in a single copy, and new airplanes are virtually impossible to build. Boeing 747-8F - 140 tons, Lockheed C-5 - 122 tons, Airbus A380F - 148 tons. For heavier missiles, it is necessary to develop new aircraft that will be expensive, complex and monstrous (like on KDPV).
Liquid fuel will require carrier rework... Cryogenic components will evaporate over a long take-off and climb time, so you need to have a supply of components on the carrier. It is especially bad with liquid hydrogen, it evaporates very actively, you will need to carry a large supply.
Structural Strength Issues of Payload and Launch Vehicle... In the West, satellites are often developed with the requirement to withstand only axial overloads, and even horizontal assembly (when the satellite lies "on its side") is unacceptable for them. For example, at the Kuru cosmodrome, the Soyuz launch vehicle is taken out horizontally without a payload, placed in the launch facility and the payload is connected there. As for the carrier aircraft, even takeoff will create a combined axial / lateral overload. I'm not even talking about the fact that in an unstable atmosphere of the so-called. "Air pockets" can seriously shake the complex. The launch vehicles were also not designed for side flights in a fueled state; for sure, not a single existing liquid fuel launch vehicle can simply be loaded into the cargo hatch and thrown into the stream for launch. It will be necessary to make new missiles, more durable, and this excess weight and and loss of efficiency.
The need to develop powerful hypersonic engines... Since an efficient launch vehicle is a fast launch vehicle, conventional turbojet engines are poorly suited. L-1011 gives only 4% height and 3% speed for Pegasus. But new powerful hypersonic engines are on the verge of current science, they have not yet been made. Therefore, they will be expensive and require a lot of time and money to develop.
Conclusion
Aerospace systems can become very effective remedy delivery of goods to orbit. But only if these cargoes are small (probably not more than five tons, if predicted taking into account the progress achieved), and the carrier is hypersonic. Attempts to create flying monsters such as a twin An-225 with twenty-four engines or some other super-heavy example of the victory of technology over common sense is a dead end at the current level of our knowledge.For navigation: posts by tag
M.N. Avilov, Ph.D.
For thirty years (1955-1985) V.P. Makeev headed the Design Bureau for Mechanical Engineering (now the State Missile Center "Design Bureau named after Academician V.P. Makeev"). The Machine Building Design Bureau created missile systems of the USSR naval strategic nuclear forces - a sea-based missile shield. The chief designer of the missile complex is the organizer of the work and interaction of many teams of specialists and enterprises, the director of the introduction of new ideas, technical solutions and technologies into the equipment being created. Under the leadership of the chief designer, endowed with such qualities, teams of specialists and cooperation of enterprises (research institutes, factories) that create and manufacture unique systems and weapon complexes. Viktor Petrovich Makeev - Chief and then General Designer of the Mechanical Engineering Design Bureau managed to organize such teams of specialists and cooperation of enterprises, which, under his leadership, created all the strategic complexes of SLBMs of the Navy, the last of which (D-9R, D-9RM and D-19) and are now in service and guard the interests of our fatherland.
The first sea-based missile system with ballistic missiles (BR) R-11FM, launched from a submarine on the surface, was adopted by the USSR Navy in 1959.The firing range of the first naval ballistic missile was 150 km, its launch weight was equal to five and a half tons , the mass of the warhead is 1100 kg. The length of the rocket is 10.3 m, its diameter is 0.88 m (the span of the stabilizers is 1.75 m). The diesel-electric submarine of AV611 pr. Had two missile silos with a diameter of 2.4 m.
Ten years after the adoption of the first SLBM complex, in 1969, joint detailed tests of the D-9 complex with an underwater launch (from a depth of 50 m) and intercontinental range shooting. In 1974, the D-9 complex was adopted by the Navy. The firing range of the R-29 rocket was 8000 km, with a launch weight of 33.3 tons, the maximum throwable weight of 1000 kg, the rocket length is 13 m, the rocket diameter is 1.8 m. The submarine of pr. 667B housed 12 launch missile silos with a diameter of 2.4 m (on the submarine pr. 667BD there were 16 mines).
Comparison of missiles shows a colossal leap achieved in their tactical and technical characteristics. One of the main characteristics - the firing range - increased almost 55 times with an increase in the launch mass of the rocket by only six times, the diameter - twice and the length of the rocket - by 2.7 m.At the same time, the missile silo increased only in height in proportion to the length of the rocket ... This turned out to be possible due to the solution of a number of problems earlier in the creation of two other complexes - D-4 (adopted for service in 1963) and D-5 (1968).
In the D-4 complex with the R-21 rocket, the following issues of underwater launch were solved and worked out:
However, the number of R-21 missiles on submarines did not exceed three. In 1958-1960. at TsKB-18, design studies were carried out for the nuclear submarine of project 667, armed with the D-4 complex, with the deployment of eight R-21 missiles. The project was distinguished by originality: the missiles were placed in the mines of four blocks in a horizontal position, two in each block. One pair of blocks with missile silos was located in the bow of the submarine, the other in the stern. In each pair of blocks, one block with two shafts was placed along the starboard side, the other along the left. The blocks of each pair were rigidly connected by a hollow axis (pipe) located perpendicular to the diametrical plane of the boat's hull. This axis could be rotated with the blocks by 90 °, and thus the missile silos from the traveling horizontal position before the prelaunch preparation were brought to the vertical position.
Already at the initial stage of work, technical problems began to be identified, the solution and implementation of which showed the unreasonableness of the further development of this project, and the work was stopped. However, the problem of increasing the number of missiles placed on submarines remained a matter of paramount importance for the Navy. The decision was closely related to the possibility of a significant reduction in the size of the ballistic missile while increasing the firing range.
As soon as the solutions were found, in 1962 it was decided to develop the D-5 complex with a small-sized single-stage R-27 ballistic missile with an average firing range of 2500 km. The complex with ammunition load of 16 missiles, placed in vertical silos, was intended for arming the SSBNs of project 667A. When creating the D-5 complex, the developers proposed and worked out the following unconventional ways to ensure the small-sized rocket:
Also, a rocket-launch system was created, which makes it possible to bring the size of the rocket as close as possible to the size of the submarine launch shaft. At the same time, the firing range of these SLBMs, although increased (R-21 - 1420 km, R-27 - 2500 km), remained at a level that limited the capabilities of the strategic nuclear forces of the Navy. Therefore, in 1964, the development of the D-9 complex with the R-29 missile, the first sea-based intercontinental ballistic missile, began.
The minimum dimensions of the two-stage rocket were achieved due to the "drowning" * of the engines, the elimination of inter-tank compartments (as in the R-27), the elimination of the interstage compartment by placing the 2nd stage engine in the 1st stage oxidizer tank and separation of the stages by the gas tank when the detonating extended charge. The dimensions of the R-29 made it possible to place on the SSBNs projects 667B and 667BD 12 and 16 BR, respectively.
* - Approx. ed. With a "recessed" scheme, the rocket engines are located in the oxidizer (fuel) tanks.
Submarine navigation support in the 1960s could not ensure the implementation of acceptable firing accuracy by intercontinental ballistic missiles with an inertial control system using traditional methods. To solve this problem, an astrocorrection system and high-precision gyroscopic devices operating in a vacuum were used on board the R-29. The development of the necessary data to ensure the accuracy of shooting required the use of high-performance small-sized digital computing systems and special software. Astrocorrection determined fundamentally new technical solutions for the rocket layout, as well as the principles of organizing prelaunch preparation.
The development of the D-9 complex was carried out taking into account the possible deployment of a missile defense system by a potential enemy. R-29 became the first SLBM equipped with missile defense penetration means. The high rate of improvement of weapons demanded hard work by the teams of development enterprises, research institutes of industry and the Navy. The role of KBM in this process was decisive. Tests and commissioning of the D-4 and D-5 complexes quite clearly revealed certain technical problems, the solution of which was necessary to improve the performance characteristics of promising SLBM complexes. Based on the experience of work on these complexes, we considered it necessary to resolve the following problems:
A group of specialists from the Institute of Armaments of the Navy (28th Scientific Research Institute of the Ministry of Defense) consisting of V.A. Emelyanova, A.B. Abramova, M.N. Avilov and V.V. Kazantseva conducted the necessary research, developing the principles of construction and formulating proposals for the implementation in a complex of a system for compensating for dynamic errors from pitching, yawing and orbital motion of submarines when leveling onboard gyro devices in the process of prelaunch preparation and ensuring the technical possibility of targeting a ballistic missile at any submarine course, as well documentation systems (the corresponding TTZ was developed). Good creative and working relations and contacts of the Institute of Armaments of the Navy with the Research Institute of Automation (NINA) and KBM to a large extent contributed to the implementation of ideas and proposals on these issues in the complexes of SLBMs of intercontinental firing range.
Ground development and testing of the R-29 missile
In 1968, the development of prototypes of prototypes of the complex of ship and onboard control systems was in full swing at the integrated stand in KBM and at the enterprises-developers of individual systems. Simultaneously, in KBM, using universal computing tools for testing the adopted scheme of operation and interaction of onboard systems, the flight trajectory of the R-29 rocket was simulated with the solution of fundamentally new problems to ensure astrocorrection of the BSU trajectory in flight under various launch conditions. Later, in a special government decree, it was pointed out that, in order to reduce the costs and time for conducting flight tests, to maximize the use of the ground testing stage, and to take out for flight tests only what can be fully tested and verified only during flight testing.
In general, the BR goes through the stages of ground development and testing at proving grounds. At the stage of testing by launches from the head submarine, the operation of the systems of the complex, including the rocket, is tested and verified, their interaction with the systems of the submarine under conditions as close as possible to real operation. After the completion of this stage of testing, a conclusion will be given on the possibility of adopting the complex for service. In terms of landfills, the following stages are envisaged:
Each of the stages of testing requires the preparation of logistics, the organization of a clear interaction between various services of the landfills and the enterprises-developers of the complex during the work, based on the results of which a conclusion is made on the possibility of moving to the next stage. As already noted, the R-29 was the first two-stage intercontinental missile, therefore, the onboard equipment, its operation and placement on the rocket, as well as its individual devices, fundamentally differed from those developed earlier. In connection with the implementation of astrocorrection of the flight trajectory in the interests of ensuring a given shooting accuracy, the volume of tasks solved in flight by onboard equipment has significantly increased. All tasks, including the stabilization of the rocket, were practically solved by the onboard digital computer complex (BTsVK). For the first time, digital technology was used on board the R-27K missile, designed for firing at sea mobile targets and accepted for trial operation in 1975. The R-29 became the second SLBM with digital equipment developed by NINA.
Due to the imperfection of the manufacturing technology, problems arose with ensuring the reliability of the BTsVK. The enterprise-developer and manufacturer, together with the lead developer of the missile complex (KBM) and the Institute of Armaments of the Navy, had to do a lot to refine the technology, test and refine the BTsVK as a whole to achieve acceptable reliability indicators. During tests and combat training launches of intercontinental-range missiles, it is imperative to take special measures to exclude the deviation of the ballistic missile from the given trajectory and the fall of the missile or its parts in territories outside the established dangerous zones.
 BR-21(all-welded stainless steel body, classic layout with inter-tank and tail compartments): 1 - instrument compartment; 2 - inter-tank compartment; 3 - tail compartment. BR-27(all-welded body made of aluminum alloy, scheme of a "recessed" engine without inter-tank and tail compartments): 1 - bottom-instrument compartment; 2 - shock absorber; 3 - wafer ribbing; 4 - double dividing bottom; 5 - "recessed" engine; 6 - the bottom-frame of the engine. P-29(all-welded body made of aluminum alloy, without interstage compartment): 1 - warhead niche bottom; 2 - double dividing bottom; 3 - engine bottom-frame; 4 - detonation extension charge of separation of stages; 5 - "recessed" second stage engine (elimination of the interstage compartment); 6 - wafer ribbing; 7 - double dividing bottom; 8 - "recessed" first stage engine; 9 - the bottom-frame of the engine. |
To ensure safety, the R-29 and all subsequent SLBMs during test and combat training launches were equipped with an emergency missile detonation system (APR) developed by the KBM. On the R-29, the APR system was located in the body of the combat unit (which the ballistic missiles are equipped with for test and combat training launches). When the missile deviates from the specified trajectory by an amount more permissible for any reason, the APR system receives a signal from the onboard gyro platform, according to which commands are formed to eliminate the missile by using standard pyrotechnics to separate its detachable elements (for example, stages). The peculiarity of the APR system is that it does not work during normal flight of the rocket (the developers even joked: they do not remember its existence either with a successful or unsuccessful launch).
The stage of throw tests of full-scale mock-ups R-29 at the southern range of the Navy in the area of Cape Fiolent was successfully completed in early 1968. Next was the stage of factory bench tests of the missile for joint flight tests (SLT) from the ground stand at the northern naval range.
Factory bench tests
In early September 1968, the author was sent to work in the commission for factory bench tests of the R-29 missile, which were carried out at the Krasnoyarsk Machine-Building Plant, a missile manufacturer. The tests were carried out on on-board equipment, which was used to equip the first SLI missile from the ground stand. Upon arrival at the Krasmash, he introduced himself, as was customary, to the district engineer of the military mission, Captain 1st Rank F.I. Novoselova (in 1969 he was appointed head of the URAV of the Navy, and in the early 1980s - head of shipbuilding and weapons of the Navy). The chairman of the bench testing commission was the head of the KBM department L.M. Oblique, and the deputy. Chairman - V.I. Shook. The working group from KBM was headed by A.I. Koksharov. The work of the commission on factory bench tests was attended by: from the Research Institute of Automation - A.I. Bakerkin, from NIIAP - V.S. Mityaev and K.A. Khachatryan, from the Central Design Bureau "Geofizika" - V.P. Yushkov, from the Krasnoyarsk Machine-Building Plant - L.A. Kovrigin and V.N. Harkin.
I happened to meet L.M. Kosym in 1961, in preparation for joint tests of the D-4 complex. At that time he was the head of the department and oversaw the work of the co-executors of the developers of the complex control system. In the future, he had to interact with him in the process of work on the D-9, D-19 and D-9RM complexes (then he became deputy chief designer). Leib Meyerovich is a sociable, benevolent person, but rather tough in carrying out the technical policy of the head developer. He was the ideologist of the organization of many works on the management system. When he chaired meetings of chief designers of co-executing enterprises to find solutions to technical problems arising in the process of developing a control system for a complex of weapons, with many disagreements, he always found and proposed ways to solve it, reconciling and motivating all participants in the work. When the situation at the meeting became tense, L.M. Oblique contrived to joke so that emotions subsided, the meeting turned into a business course, and, as a rule, it was worked out constructive solution question. When analyzing and identifying the causes of unsuccessful launches, malfunctions in systems during testing, Leib Meyerovich suggested from the very beginning to work in a direction leading to positive results. And this is possible only with an excellent (down to the details) knowledge of the hardware and the organization of the interaction of the complex systems and the measurement system.
During breaks in work, there was an opportunity to get acquainted with the work of the shops in which the elements of the rocket body were manufactured, with the technology, in particular, with the use of mechanical and electrochemical milling in their manufacture. I managed to get to know the design of the rocket well. Factory bench tests were carried out in the assembly shop and adjacent premises. The workshop was a well-lit space about the size of a football field. At that time, the assembly of the 8K65 missiles used to launch the Molniya communications satellites and our R-27 was underway there. Compared to the 8K65, the P-27 and P-29 felt like a match compared to a thick pencil and were barely visible in the huge assembly hall.
Due to the complexity of mounting and dismantling the onboard equipment in the instrument compartment ** P-29 with a high filling factor, the tests were carried out in two stages. At the first stage, the onboard equipment was located on special racks and connected by replaceable cables with steering gears and other controllable elements that are located on the rocket (outside the instrument compartment). This made it possible to have easy access to it in the event of violations in the operation and installation of equipment, and, if necessary, to quickly replace the devices. After checking the installation and testing the interaction of the devices and their interaction with the control and testing equipment (KPA), the onboard equipment was installed in the instrument compartment of the rocket, and then the operation of the equipment as a part of the instrument compartment was checked (tested). After that, the instrument compartment was connected to the rocket assemblies and the functioning of the BSU as part of the rocket was checked. During the checks, the monitored parameters were recorded by a telemetry system without broadcasting. For camouflage purposes, telemetry information was transmitted via cable (this deviation from real conditions later led to the need to refine the cable connections in the instrument compartment under the conditions of the test site).
** - Approx. ed. The R-29 instrument compartment is a separate structure and is installed on the rocket after installation, verification of the equipment installed in it and docking with the warhead. To ensure a high filling ratio, individual devices had a complex shape, for example, in the form of a part of a torus.
In December 1968, factory bench tests were completed and an act was signed on the readiness of the first P-29 missile to be sent to the State Central Maritime Range (MCMP) for SLI from the ground stand. In January of the next year in Miass, the Council of Chief Designers, which met at the KBM, considered the issue of readiness and decided to start flight tests of the D-9 complex missile from the ground stand. At that time, the Neptune hotel was still under construction in Miass (funds were allocated specifically for this purpose on the D-9 project), and the existing one was small, so some of the representatives who arrived at the Council of Chief Designers were housed in private apartments. I remember that the employees of TsNII-28 S.Z. Premeev, V.K. Shipulin, Yu.P. Stepankov and I lived in a one-room apartment of a residential building opposite the hotel under construction, and V.M. Latyshev and A.A. Antonov - in the abortion clinic of the polyclinic, among the medical equipment.
Joint flight tests from the ground stand
Tests of the P-29 from the ground stand began at the MCMP in March 1969 and ended at the end of 1970. The Chairman of the State Commission was Rear Admiral R.D. Novikov, the technical leader of the tests is the chief designer of KBM V.N. Makeev. Members of the State Commission from the Research Institute of Armament of the Navy were V.K. Svistunov and H.P. Prokopenko. The permanent contingent of our employees during the tests included: V.K. Svistunov - leader of the D-9 complex from the Navy and secretary of the State Commission, S.Z. Eremeev, S.G. Voznesensky, M.N. Avilov, V.A. Kolychev and Yu.P. Stepankov. L.S. Avdonin and V.K. Shipulin headed the analysis group, whose tasks included organizing the analysis of the launch results, the State Commission report on the launch results and the preparation of the launch report. Other specialists came to address specific issues that arose in the testing process (V.A.Vorobyov, V.V. Nikitin, A.A. Antonov, V.F. Bystrov, A.S. Paeevsky, A.B. Abramov, V.V. . E. Gertsman).
In March 1969, the author was sent on a business trip to test the P-29 from the ground stand (VK Svistunov and VA Emelyanov were already working there). The ground stand, the technical position for the preparation of missiles and the hotel for the testers were located several tens of kilometers from Severodvinsk, not far from the village of Nyonoksa. *** Work with the rocket at the technical position was in full swing, but the launch of the first P-29 missile from the ground stand was delayed in connection with the need to modify the cables in the instrument compartment of the rocket. During the operation of telemetry with radiation on the air at the test site, the influence of the radiation of the telemetry channel on the operation of the BTsVK was discovered, which was caused by the use of unshielded cables in the communication lines of the BTsVK with other equipment.
*** - Approx. ed. There was a large wooden church in the village, built (as they say, without a single nail) in 1727 - this is the only surviving five-hipped church.
After the completion of all work with the rocket and the systems of the ground stand, they were made ready for launch. After listening to the reports on the readiness of the chief designer and the chiefs of the landfill services. The State Commission approved the flight task and decided on the launch time. The first launch from the ground stand was successful, confirming the correctness of technical solutions for fundamentally new tasks and for their implementation in on-board equipment, incl. on astrocorrection, digital automatic stabilization, BTsVK, on the dynamics of separation on the trajectory of the rocket elements (stages, astrodome and the front compartment, consisting of the instrument compartment and the warhead).
The success of the first launch caused a rise in the moral, mental and physical strength of the testers - the long-term work of the teams of many enterprises and organizations of the creators of the first intercontinental SLBM was crowned with success! But this is only the first practical step. Testers know that the path to success always lies through overcoming mistakes, mastering new technical, technological, organizational, operational factors that accompany the creation of new complex equipment. A special role in flight tests is assigned to "complex specialists" who are well aware of the operation and interaction of all tested systems. Such tests, as a rule, reveal malfunctions, failures and failures in the operation and interaction of the tested systems, due to technological, design, production and operational factors. The main task of the "complexist" is to be able to quickly and as accurately as possible establish which elements, devices, equipment, processes could be the causes of deviations from the normal functioning of the tested equipment, based on the information received during the testing process (from measuring instruments or on the fact of a malfunction) such a deviation. This is necessary to determine the specific "culprit" and possible reasons for the rejection. If necessary, "narrow" specialists are involved, and recommendations are developed for prompt elimination and exclusion of repetition of the identified deviations.
The time spent on finding and eliminating the causes of deviation from the normal operation of the tested equipment ultimately affects the duration of the tests, the timing of which is strictly defined and limited. The flight test program from the ground stand provided for 16 launches. The first three, sixth, seventh, eleventh, twelfth, thirteenth and fifteenth launches were successful. On the fourth, fifth and tenth in-flight launches, the BCVK failed, on the eighth - premature reset of the astrodome, on the ninth - the signal from the rocket lift contact did not pass, on the fourteenth - the bleeding of air from the instrument compartment did not pass. With all these unsuccessful launches, the APR system worked. The reason for half of the failures (4th, 5th and 10th launches) was the insufficient reliability of the BTsVK, which was the reason for a sharp intensification of work aimed at increasing the reliability of digital technology. Taken measures provided the required level of reliability already by the stage of flight tests of the complex with submarines. The second half (8th, 9th and 14th launches) revealed flaws that could not be detected during ground testing. Observations identified during successful launches also provided information for the refinement of individual systems and their elements.
One launch during tests from a ground stand did not take place. It was planned at the very end of December, on New Year's Eve 1970. The preparation of the rocket at the technical position took place without any special remarks. The rocket was loaded into the mine of the ground stand, routine checks were carried out, and the State Commission decided to launch. On the day of the launch, all the services of the range and combat zero were involved, providing the launch. The launch time, as usual, was evening. The test participants took their places. V.P. Makeev watched the prelaunch preparations in the bunker. Automatic prelaunch preparation ended with the issuance of a command to start the rocket engine, but it did not start. The rocket remained in the stand shaft. As provided in such cases, an emergency engine shutdown (AED) was automatically passed. The start was canceled. The testers were asked a question that was usual for them in form (what is the reason?) And specific in content (the reason for not starting the rocket engine). Possible reasons for non-launch of the rocket propulsion system are immediately analyzed. As a result of the analysis, it was found that the most likely reason for the non-starting of the remote control could be the failure of the mechanism to prevent the launch of the remote control of the first stage. This assumption was confirmed. A working group was appointed to identify the reasons for the failure of the protection mechanism and develop proposals to ensure the normal operation of this mechanism. The author was instructed to represent the Naval Weapons Institute on this working group.
New Year was celebrated in Nyonoks. New Year's tables were set in the dining room. V.P. Makeev gave a brief assessment of the results of the work, talking about the tasks of the testers next year, then congratulated everyone on the New Year. In January, the working group moved to the chemical engineering design bureau in Moscow) to the chief designer A.M. Isaev. About A.M. Isaev was told, for example, that he does not have a special salon in the canteen at his enterprise for management (on this occasion, he was sometimes teased by his colleagues - chief designers of other enterprises). During my stay at KBHM, one could be convinced of this. A.M. Isaev dined in the common self-service room.
The working group established the reason for the failure of the safety mechanism: it turned out that there was a deviation in the heat treatment technology of the moving element of the mechanism. It caused the movable element to jam during prelaunch preparation - when the command was given to cocking the safety mechanism, it did not work, which is why the engine did not start when the command was given to start the remote control. We have developed proposals, the implementation of which excluded the failure of the protection mechanism. Further tests and operation of the R-29 rocket did not reveal any deviations from the normal operation of the protection mechanism.
Thanks to the clarity and good organization of accounting and the elimination of all comments, malfunctions, improvements, the main schedule of missile launches from the ground stand was observed. The testers who showed good knowledge of the materiel during the tests, which contributed to the prompt identification and elimination of the causes of malfunctions and comments, were always encouraged by V.P. Makeev, who greatly appreciated the observation and ability to analyze situations that arise when working with the tested technique. I remember that during routine checks of the rocket in the shaft of the ground stand at a certain second, the check mode was canceled. A possible cause was identified and corrected in the ground control system hardware. A corresponding entry was made in the journal. The checks and launch of this and the next missile went well, but when the next missile was checked, the mode was canceled. For several days we were looking for the reason, we analyzed the schemes. Unsuccessfully. And time went on. When analyzing deviations from the norm during the functioning of the tested systems, V.P. Makeev always listened attentively to the opinions and suggestions of the testers. The head of the KBM department Pavel Sergeevich Kolesnikov, comparing the operation of the ground equipment scheme of the control system when the check mode of the next missile failed and when the check mode was canceled, a possible reason for which was previously eliminated, established a circuit connection between these events. The necessary changes were made in the circuit and in the equipment, and the work went on. V.P. Makeev thanked P.S. Kolesnikov. Soon he was appointed deputy. chief designer of KBM, and in this position he worked very successfully until retirement.
In May 1970, flight tests of the R-29 from the ground stand came to an end. The 16th launch remained, which was supposed to be the last one according to the stage program. After that, a decision should be made about the possibility of moving to the SLI stage with a PL. The State Commission heard the reports of the chief designer and the landfill services on readiness, a decision was made. The launch time, as always, was in the evening, about 20-21 hours Moscow time. It was light. Participants of the tests, not occupied at the starting position and at the point for recording and reproducing telemetric information, were at the measuring point one kilometer from the starting position. They received information about the course of prelaunch preparation and about the flight of the rocket. Prelaunch preparation went without comment, the launch took place, but the rocket, having risen ten meters above the stand, crashed to the ground. As it turned out later, the engine did not come out on mode. From the measuring point, a high-flying column of flame and smoke was observed with a mushroom cloud above it - there was an almost instantaneous merger and ignition of about 30 tons of rocket fuel components. The tests could not end with an emergency launch ...
After the emergency launch, a meeting of test participants was held in the training ground club, V.P. Makeev. He outlined the complexity of the situation, asking everyone to be careful in the performance of their duties and in identifying the causes of the accident, adding that testing from the ground stand should be continued. After him, the chief designer of the rocket engine A.M. Isaev, saying that the specialists of his enterprise must understand everything and take measures to exclude the possibility of a repetition of such a situation. Then the political officer of the polygon came to the podium. At his first words, a portrait of Lenin fell, hanging on the stage behind him. The situation was comic, but the seriousness of the situation and what was happening did not even allow one to smile. They announced a break.
A break was also made in the tests of the rocket from the ground stand. The area around the stand shaft was polluted with toxic fuel components, the soil and the remains of the rocket floated for several days. The bunker with the equipment near the stand (the presence of people in this bunker during the prelaunch preparation and launch was not allowed) was also gassed through the tunnels in which cables and fittings were laid from the stand shaft. The bunker from which the prelaunch preparation and launch was controlled was located further from the stand and was connected to the stand through the bunker closest to the stand. People and equipment in this bunker were not harmed. To carry out work on bringing the stand and working condition, it was necessary to degass the area, all communications of the stand, cables, equipment and the premises of the nearby bunker. Two days after the accident, we went to look from afar at the stand and the remains of the rocket. At this time V.P. Makeev and from the edge of the site studied the stand and everything that surrounded it for a long time. It was decided to transfer four missiles from the submarine stage to continue and complete tests from the ground stand. Throughout the summer months, work was going on to degass the stand, equipment, terrain, and to prepare the stand for the continuation of tests.
The last four launches from the ground stand were almost without comment. In November 1970, a report was drawn up by the State Commission on the implementation of the program for testing the R-29 missile of the D-9 complex from the ground stand and a decision was made on the possibility of moving to the stage of joint flight tests of the D-9 complex with submarines. In December 1972, joint flight tests of the D-9 complex with salvo fire (four-rocket salvo) from the lead SSBN project 667B were successfully completed, and on March 13, 1974, the complex was adopted by the Navy. And on July 3, 1981, for the first time in world practice, volley firing of strategic SLBMs from the high-latitude region of the Arctic Ocean, covered with solid ice... A two-rocket salvo with R-29D missiles from the ice position was fired by the SSBN pr. 667B.
In which there is no thrust or control force and moment, it is called a ballistic trajectory. If the mechanism that drives the object remains operational throughout the entire time of movement, it belongs to a number of aviation or dynamic ones. The trajectory of the aircraft during a flight with the engines turned off high altitude can also be called ballistic.
An object that moves along given coordinates is acted upon only by the mechanism that sets the body into action, the forces of resistance and gravity. A set of such factors excludes the possibility of rectilinear motion. This rule works even in space.
The body describes a path that is like an ellipse, hyperbola, parabola, or circle. The last two options are achieved at the second and first cosmic speeds. Parabolic or circular motion calculations are performed to determine the trajectory of a ballistic missile.
Taking into account all the parameters during launch and flight (mass, speed, temperature, etc.), the following trajectory features are distinguished:
- In order to launch the rocket as far as possible, you need to find the right angle. The sharpest is best, about 45º.
- The object has the same start and end speed.
- The body lands at the same angle as it launches.
- The time of movement of the object from the start to the middle, as well as from the middle to the finish point, is the same.
Trajectory properties and practical implications
The movement of the body after the termination of the influence of the driving force on it is studied by external ballistics. This science provides calculations, tables, scales, sights and develops the best options for shooting. The ballistic trajectory of a bullet is a curved line that describes the center of gravity of an object in flight.
Since the body is influenced by the force of gravity and resistance, the path that the bullet (projectile) describes forms a curved line. Under the action of the reduced forces, the speed and height of the object gradually decreases. There are several trajectories: flat, hinged and coupled.
The first is achieved by using an elevation angle that is less than the angle of greatest range. If the flight range remains the same for different trajectories, such a trajectory can be called conjugate. In the case when the elevation angle is greater than the angle of the greatest distance, the path acquires the name of a hinged one.
The trajectory of the ballistic movement of an object (bullet, projectile) consists of points and sections:
- Departure(for example, the muzzle of the barrel) - this point is the beginning of the path, and, accordingly, the reference.
- Weapon horizon- this section passes through the departure point. The trajectory crosses it twice: on release and fall.
- Elevation plot is a line that is a continuation of the horizon and forms a vertical plane. This section is called the firing plane.
- Trajectory vertices is the point halfway between the start and end points (shot and fall) and has the highest angle along the entire path.
- Hovering- the target or the place of the sight and the beginning of the movement of the object form the aiming line. The aiming angle is formed between the horizon of the weapon and the final target.
Rockets: Launch and Movement Features
Distinguish between guided and unguided ballistic missiles. The formation of the trajectory is also influenced by external and external factors (drag forces, friction, weight, temperature, required flight range, etc.).
The general path of the neglected body can be described by the following stages:
- Launch. In this case, the rocket enters the first stage and begins its movement. From this moment, the measurement of the altitude of the trajectory of the ballistic missile flight begins.
- After about a minute, the second engine starts.
- 60 seconds after the second stage, the third engine starts.
- Then the body enters the atmosphere.
- In the last turn, the explosion of the warheads occurs.
Rocket launch and travel curve formation
The rocket travel curve consists of three parts: the launch period, free flight and re-entry into the earth's atmosphere.
War shells are launched from a fixed point of portable installations, as well as Vehicle(ships, submarines). Bringing into flight lasts from tenths of a thousandth of a second to several minutes. Freefall makes up the largest portion of a ballistic missile's flight path.
The advantages of running such a device are:
- Long free flight time. Thanks to this property, fuel consumption is significantly reduced in comparison with other rockets. For the flight of prototypes (cruise missiles), more economical engines (for example, jet) are used.
- At the speed with which the intercontinental weapon moves (about 5 thousand m / s), interception is given with great difficulty.
- A ballistic missile is capable of hitting a target at a distance of up to 10 thousand km.
In theory, the path of movement of the projectile is a phenomenon from the general theory of physics, the division of the dynamics of rigid bodies in motion. With regard to these objects, the movement of the center of mass and movement around it is considered. The first relates to the characteristics of the object in flight, the second to stability and control.
Since the body has programmed trajectories for flight, the calculation ballistic trajectory rocket is determined by physical and dynamic calculations.
Modern developments in ballistics
Insofar as combat missiles of any kind are hazardous to life, the main task of defense is to improve the points for launching destructive systems. The latter must ensure the complete neutralization of intercontinental and ballistic weapons at any point in the movement. A multi-tiered system is proposed for consideration:
- This invention consists of separate tiers, each of which has its own purpose: the first two will be equipped with laser-type weapons (homing missiles, electromagnetic guns).
- The next two sections are equipped with the same weapons, but designed to defeat the warheads of enemy weapons.
Developments in defense rocketry do not stand still. Scientists are modernizing a quasi-ballistic missile. The latter is presented as an object having a low path in the atmosphere, but at the same time dramatically changing direction and range.
The ballistic trajectory of such a missile does not affect the speed: even at extremely low altitudes, the object moves faster than an ordinary one. For example, the development of the Russian Federation "Iskander" flies at a supersonic speed - from 2100 to 2600 m / s with a mass of 4 kg 615 g, missile cruises move a warhead weighing up to 800 kg. During flight, maneuvers and evades missile defense.
Intercontinental weapons: control theory and components
Multistage ballistic missiles are called intercontinental missiles. This name appeared for a reason: due to the long flight range, it becomes possible to transfer the cargo to the other end of the Earth. The main warhead (charge), basically, is atomic or thermonuclear substance. The latter is placed in front of the projectile.
Further, a control system, engines and fuel tanks are installed in the design. Dimensions and weight depend on the required flight range: the greater the distance, the higher the starting weight and dimensions of the structure.
The ballistic trajectory of an ICBM is distinguished from the trajectory of other missiles in height. The multistage rocket goes through the launch process, then moves upward at a right angle for several seconds. The control system provides the direction of the weapon in the direction of the target. The first stage of the rocket drive, after complete burnout, is independently separated, at the same moment the next one is launched. Upon reaching a given speed and altitude, the rocket begins to rapidly move down to the target. The flight speed to the destination reaches 25 thousand km / h.
World development of special-purpose missiles
About 20 years ago, during the modernization of one of the medium-range missile systems, a project for anti-ship ballistic missiles was adopted. This design is placed on an autonomous launch platform. The weight of the projectile is 15 tons, and the launch range is almost 1.5 km.
The trajectory of a ballistic missile to destroy ships is not amenable to quick calculations, so it is impossible to predict the enemy's actions and eliminate this weapon.
This development has the following advantages:
- Launch range. This value is 2-3 times higher than that of prototypes.
- The flight speed and altitude make combat weapons invulnerable to missile defense.
World experts are confident that weapons of mass destruction can still be detected and neutralized. For such purposes, special reconnaissance ground-based stations, aviation, submarines, ships, etc. are used. The most important "counteraction" is space reconnaissance, which is presented in the form of radar stations.
The ballistic trajectory is determined by the reconnaissance system. The received data is transmitted to its destination. The main problem is the rapid obsolescence of information - in a short period of time, the data loses its relevance and can diverge from the real location of the weapon at a distance of up to 50 km.
Characteristics of combat systems of the domestic defense industry
The most powerful weapon of the present time is considered to be an intercontinental ballistic missile, which is stationary. Domestic missile system "R-36M2" is one of the best. It houses the 15A18M heavy-duty combat weapon, which is capable of carrying up to 36 individually precise targeting nuclear projectiles.
The ballistic trajectory of such a weapon is almost impossible to predict; accordingly, the neutralization of the missile also presents difficulties. The combat power of the projectile is 20 Mt. If this ammunition explodes at a low altitude, communication, control, and anti-missile defense systems will fail.
Modifications of the given rocket launcher can also be used for peaceful purposes.
Among solid-propellant missiles, the RT-23 UTTH is considered to be especially powerful. Such a device is based autonomously (mobile). In the stationary prototype station ("15Zh60"), the starting thrust is 0.3 higher in comparison with the mobile version.
The launch of missiles, which is carried out directly from the stations, is difficult to neutralize, because the number of shells can reach 92 units.
Missile systems and installations of the foreign defense industry
The height of the ballistic trajectory of the missile of the American complex "Minuteman-3" does not differ much from the characteristics of the flight of domestic inventions.
The complex, which was developed in the United States, is the only "defender" of North America among such weapons to this day. Despite the age of the invention, the stability indicators of the gun are still quite good at the present time, because the missiles of the complex could withstand anti-missile defense, as well as hit a target with a high level of protection. The active part of the flight is short, and is 160 s.
Another American invention is the Piskiper. He could also ensure accurate hitting the target thanks to the most advantageous trajectory of ballistic movement. Experts say that the combat capabilities of the given complex are almost 8 times higher than that of the Minuteman. The Piskiper was on alert for 30 seconds.
Projectile flight and movement in the atmosphere
From the section on dynamics, the influence of air density on the speed of movement of any body in various layers of the atmosphere is known. The function of the last parameter takes into account the dependence of the density directly on the flight altitude and is expressed as a function of:
H (y) = 20,000-y / 20,000 + y;
where y is the height of the projectile flight (m).
The calculation of the parameters, as well as the trajectory of an intercontinental ballistic missile, can be performed using special computer programs. The latter will provide statements, as well as data on flight altitude, speed and acceleration, the duration of each stage.
The experimental part confirms the calculated characteristics, and proves that the speed is influenced by the shape of the projectile (the better the streamlining, the higher the speed).
Guided weapons of mass destruction of the last century
All weapons of this type can be divided into two groups: ground and aircraft. Ground-based devices are those that are launched from stationary stations (for example, mines). Aviation, respectively, is launched from a carrier ship (aircraft).
The group of ground-based missiles includes ballistic, cruise and anti-aircraft missiles. For aviation - projectile aircraft, ADB and guided air combat projectiles.
The main characteristic of calculating the ballistic trajectory of movement is the height (several thousand kilometers above the atmosphere). At a given level above the level of the Earth, the projectiles reach high speeds and create enormous difficulties for their identification and neutralization of missile defense.
Well-known ballistic missiles, which are designed for an average flight range, are: "Titan", "Thor", "Jupiter", "Atlas", etc.
The ballistic trajectory of a missile, which is launched from a point and hits the given coordinates, has the shape of an ellipse. The size and length of the arc depends on the initial parameters: speed, launch angle, mass. If the speed of the projectile is equal to the first space speed (8 km / s), the combat weapon, which is launched parallel to the horizon, will turn into a satellite of the planet with a circular orbit.
Despite the constant improvement in the field of defense, the flight path of the combat projectile remains practically unchanged. At the moment, technology is not able to break the laws of physics that all bodies obey. A small exception is homing missiles - they can change direction depending on the movement of the target.
The inventors of anti-missile systems are also modernizing and developing a weapon to destroy a new generation of weapons of mass destruction.
60 years after the last Kongreva rocket was launched, the military rocket was reborn for history in the mountains near Geok Tepe. It cannot, of course, be said that military missiles did not exist at all for such a long period of time. No, they were there, but they appeared rarely and were used hesitantly, mostly in the order of experimentation or in the absence of better means.
The first attempt to put the missiles back into the service of the army after the disbandment of all old missile units was made in Sweden. Around 1890, Swedish inventor Lieutenant Colonel von Unge presented Alfred Nobel with the "air torpedo" design, which was a large missile very similar to Gale's combat missiles, but with minor modifications and improvements.
Von Unge set out to make the rocket a more effective weapon. For this, he proposed to ignite the rocket engine not from behind, through a nozzle, but from the front, through a thin hole drilled in the nose of the rocket. Another, even more important innovation was to launch the missile from a short-barreled mortar. In this case, the rocket would take off at a certain speed, say 100 m / s, which would not only increase its range, but also increase the accuracy of the missile firing, and this, according to von Unge, would give the missiles the opportunity to compete with artillery ...
Nobel's interest in von Unge's rockets was not purely academic. He put his compatriot to work, paying all of his rapidly growing bills, which to a person with less capital than Nobel might seem prohibitively large. However, despite significant expenses, von Unge was unable to complete any of his projects so that it could be shown to military specialists. In 1896, Nobel died, and von Unge was obviously out of work.
Five years later, in 1901, Mars was established in Stockholm with the goal of giving von Unge the opportunity to complete the work he had begun. The results of these experiments were not published, but some facts became known later in a roundabout way. The powder charge of the von Unge missiles was the same as that of the coastal rescue rocket (linomet): it consisted of a mixture of black powder with crushed coal and pressed into the rocket body by hand. A warhead with a dynamite charge was attached to the rocket body; the detonating fuse was triggered when the missile met the target (Fig. 28).
Fig. 28. "Air torpedo" von Unge.
Sectional view of the last 762mm model tested by Krupp in 1909.
The weight of the warhead was 2 kg with a total length of the "air torpedo" of 750 mm and a diameter of 110 mm. Fully equipped, the first models weighed up to 35 kg, developed a speed of about 300 m / s on a trajectory and had a range of up to 5 km. The mortar, which served as a launcher for these "torpedoes", gave them an initial speed of 50 m / s, which was impossible to increase due to the design features of the "torpedoes" themselves. The accuracy of the fire was admittedly unsatisfactory. Experts calculated that to hit a specific target with missiles at a distance of 3 km required at least five times more ammunition than to hit the same target when firing from a conventional field howitzer of the same caliber.
Then von Unge decided to completely abandon the mortar, and instead use an open tubular guide. In 1908, von Unge began advertising his "aerial torpedoes" as weapons for airships. At the same time, he emphasized the recoillessness of "air torpedoes", which has great importance for aircraft weapons.
In 1909 it became known that Friedrich Krupp's firm in Essen had bought von Unge's patents, as well as the stock of "air torpedoes" (about 100 pieces), a tubular guide and other equipment. All this was transported from Stockholm to the Krupp training ground in Meppen, where the "torpedoes" were subjected to extensive testing.
Some data on the latest models of this rocket were reported later by the leading specialist of the Krupp firm on ballistics, Professor Otto Eberhard, during a discussion on the mathematical calculation of the trajectories of projectiles. Eberhard said that the "air torpedoes" had a starting weight of up to 50 kg and a firing range of about 4-5 km.
In 1910, Krupp announced that experiments with von Unge's "air torpedoes" had been discontinued due to the impossibility of obtaining the required accuracy of fire. Of course, no one believed this statement, if only because just a few months earlier, the Krupp company applied for a patent on this invention. It is possible that the application was a matter of principle, or maybe it was the usual procedure of this large military-industrial firm. In any case, the Germans did not have any weapons in any way similar to von Unge's "air torpedoes" during the First World War. In all likelihood, Krupn's engineers tried to convert the von Unge missiles into heavy artillery with a short range and, when they failed, turned their attention to other means. The only country to use the missiles on the battlefields of World War I was France. Information about this can be found in the book of Captain Ernst Lehmann, who died in the Hindenburg airship crash near Lakehurst.
“During the first months of 1916,” writes Lehmann, “I commanded the new LZ-90 airship, one of seven airships at the disposal of the Army High Command ... Once we were tasked with bombing the railway depot at Bar-le- Du, through which the French supplied their troops defending key positions at Verdun. The LZ-90 airship carried a large stock of bombs (over 3000 kg). Turning off the engines and hiding in the clouds, we crossed the front line at an altitude of 3000 m. I do not know whether we were detected or not, but in any case, over Bar-le-Du, we appeared unexpectedly for the enemy, who met us with only a few ordinary shells. We did not have time to drop the first load of bombs, as we were forced to stop bombing, as the LZ-90 slipped over the target. We made a new approach and were just about to launch a second attack on the station, when we saw several clumsy yellow missiles flying slowly towards us. They passed our airship, which at that time was at an altitude of 3260 m, and continued to climb. Incendiary rockets! The last and most reliable means of igniting a hydrogen-filled airship. One hit is definitely enough to destroy any airship! I gave the order to give full speed ahead and, having raised the airship to the maximum height, safely escaped the shelling. I managed to notice that incendiary rockets were launched from the highway near the railway station and that the launchers were cars that moved along the highway. "
But the French have not only created anti-aircraft missiles; they also did what von Unge tried to do — the first air-to-air missiles. True, this task was greatly facilitated by the presence of such vulnerable air targets as an airship and a balloon. Using the experience of the American Civil War, the Germans raised their observers on tethered balloons to adjust artillery fire. The stationary balloons were filled with hydrogen and sometimes lighting gas, and the French easily destroyed them with the help of large Le Prieur missiles, similar to those used to feed the cable from the shore to the ship. These missiles, apparently, did not even have special warheads: their incendiary action was quite enough to destroy the balloon.
A Nieuport-type aircraft was used as a missile carrier - a biplane, which had very strong V-shaped vertical struts on each side of the fuselage, which connected both wings. Four Le Prieur missiles were suspended from each brace. After a series of combat tests, the French formed several special squadrons of Nieuport aircraft armed with such missiles, but these squadrons did not last long, as the Germans soon stopped lifting tethered balloons.
I read somewhere that Russian pilots had similar weapons to fight the same targets. However, very few sources have survived that describe the operations of the Russian army during the First World War. Therefore, it remains to assume that Russian aircraft missiles were only a product of the inventive activity of individual pilots.
On the western front, the Germans used large rockets to make passages in barbed wire. For this, a cable was attached to the rear of the rocket, and a small boat anchor was attached to the warhead. The rocket equipped in this way was launched from the first trench through the barbed wire, and then the anchor was pulled back using a hand winch.
This is all that can be said about the military use of missiles during the First World War. The extremely limited use of military missiles in the First World War and their abundance in the Second are not explained by chance or narrow-mindedness of the military; nor can it be explained by any definite tactical doctrine. This difference is rather related to the solution of such industrial problems as the problems of production, storage and safety of the fuel used.
When Congreve defended himself against critics, he did so by comparing the characteristics of missiles with the costs of their production. His figures were absolutely correct and convincing, but in modern conditions they would characterize only a very small part of the general problem. Judging by the way things are now, any combat missile must meet all the requirements for a standard military weapon.
The first such requirement, often overlooked due to its obviousness, is the possibility of long-term storage. finished weapon... Weapons are manufactured, say, in Detroit, then they must be stored somewhere until they are sent to some arsenal or to a military base, where the question of its storage will again arise. After a while, it may be sent either to Africa or to Greenland and will again need storage. Finally, it will be delivered to the front line for the upcoming operation. During this time, the weapon, at least in theory, should be ready for immediate use. All artillery and small arms, from cartridges for a pistol to shots for an anti-aircraft gun, meet this requirement. The second most important requirement is that the weapon should be in mass production, if possible fully automated.
When you think about these two basic requirements, it becomes clear why a liquid-propellant missile can only be used as a combat missile in some special cases. Of course, parts of a liquid-propellant rocket can also be mass-produced, and the rocket can be stored assembled or disassembled. But it would be very difficult to store a liquid-propellant rocket in a fueled form, even if there is no liquid oxygen in its fuel components. The fuel components would have to be stored separately and not refueled with them until the rocket was actually used. This is possible only in the conditions of stationary firing positions, similar to the positions of anti-aircraft artillery defending settlements, or deck installations of missile-carrying ships. But this cannot be done near the front line.
Thus, logically, combat missiles should be solid-propellant missiles, convenient for long-term storage, and at the same time meet the conditions of mass production.
The latter requirement for large black powder rockets was not met until 1935. The production of these missiles was manual, individual. Even the perfectly perfect Zander hydraulic presses freed the worker only from the use of muscular force. It was still a makeshift and dangerous job. The storage of large black powder rockets was also extremely difficult. The rocket powder charge could not withstand long-term storage, unless, of course, special conditions were created.
The reason for this is that for high-power powder rockets, the powder mixture must be pressed to a much greater extent than for small pyrotechnic rockets. The specific gravity of the charge of pyrotechnic rockets is approximately 1.25. The rockets made by Zander for the Opel experiments had specific gravity about 1.5 or even 1.7. Of course, such a charge density improved the characteristics of the missiles, but thanks to this, the pressed powder mixture became excessively fragile, much more fragile than the usual one. If rockets with a large compressed powder charge are subjected to temperature changes, then in the charge, imperceptible cracks are likely to appear. When such a rocket is launched, its characteristics will be normal until the flame reaches a crack. Then the combustion surface will increase sharply due to the crack, which will lead to an equally sharp increase in gas formation. In the best case, unburned - pieces of powder mixture will be thrown out. But usually the rocket body cannot withstand a sudden increase in pressure, which increases even more if the nozzle becomes clogged with unburned pieces of powder.
It was these cracks that caused the explosions during the Opel experiments. A sudden drop in temperature, slight carelessness during transportation - and the rocket became explosive. That this was not a purely academic concern is confirmed by the refusal of the German railways transport these missiles.
There was another problem: if the rocket on black powder was large, then its body had to be made of metal, and when burning lasted more than 1-2 seconds, the metal wall transferred enough heat to ignite the powder at the point to which the flame was still didn't get it.
Every explosives specialist who was introduced to these problems, of course, immediately suggested switching from compressed black powder to artillery. We all know the pasta-like smokeless powder tubes used in artillery ammunition. These thin and rather long tubes are known for their strength and even flexibility. Propellants of this type can withstand rough handling and extreme temperature fluctuations.
Apparently, the first person to begin such experiments with smokeless propellants was Professor Goddard. He was primarily interested in the rate of expiration of combustion products of smokeless propellants, wishing to obtain a basis for further calculations.
It may be, however, that Friedrich Sander was the first to try his hand at such missiles. According to Max Valier, who witnessed Zander's first experiments on smokeless powders, this happened shortly after the tests of Opel's rocket cars. The first results were discouraging. After a few seconds of even, but very violent combustion, an explosion usually occurred. I do not know what Zander's mistake was; perhaps it had the wrong composition of the mixture, or maybe part of the charge adjacent to the walls of the combustion chamber heated up more than necessary due to the heat transfer of the metal walls. Probably played some role in this and too long length Zander missiles. In any case, this problem turned out to be too complex for him to solve. Nevertheless, the speed of the outflow of gases in Sander's missiles, according to the same Valier, was over 1800 m / s.
Later, during the Second World War, two-base gunpowders were used as fuel in combat missiles. This term requires clarification. Initially, pyroxylin was chosen to replace the gunpowder in the guns. However, with every attempt to accomplish this, the barrel of the gun was torn. Obviously, pyroxylin burned too quickly, and therefore it was necessary to somehow slow down the combustion process. This was done by immersing finely chopped pyroxylin in a vessel with acetone. Acetone did not dissolve pyroxylin, but softened it to a jelly-like state. Then this jelly-like mass was mixed with ordinary charcoal, partially dried and rolled into thin sheets, which were cut into small squares or diamonds. So the monobasic gunpowder was prepared. The recipe for two-base gunpowder was first compiled by Alfred Nobel and was called cordite, or ballistite. These terms are still used today, although the composition and manufacturing process of these propellants have changed several times since then.
The two bases of cordite (ballistite) are two explosives - nitroglycerin and nitrocellulose (pyroxylin is one of the types of nitrocellulose). The main distinguishing feature of the production process of these substances is the gelatinization of nitrocellulose with the help of nitroglycerin. But since nitroglycerin is by no means the most perfect gelatinizer, additional reagents are used in the preparation of these substances. British explosives experts, for example, use diethyl diphenyl carbamide, which is known in the British industry as carbamite. It is not only a gelling agent, but also an excellent stabilizer that neutralizes the decomposition products of nitrogen ethers. Without it, dibasic gunpowder becomes unreliable or simply unsafe after some time.
Below is the weight composition of the English cordite:
The production process for cordite is commonly referred to as dry solution-free. Indeed, this process is solutionless, but not completely dry. The soft shapeless pulp of nitrocellulose, which is moistened with water, is fed into a tank with water, where it is mixed and where the required amount of nitroglycerin is simultaneously introduced into it. After a while, this mixture is fed into another tank with carbamite, from where, after a short stirring, the resulting raw pulp is sent to drying tables, very similar to those used in papermaking.
Here the pulp is cut into sheets of a pasty mass containing 20-25% water, which is evaporated when the sheets are dried with heated air. The dried sheets are then passed through heated rollers. Heat and pressure lead to gelatinization of the mass. After that, the gelled sheets are rolled under high pressure and placed in heated cylinders, from which they are squeezed out through a die.
In the United States, the question of the use of smokeless powder for missile powder charge was first raised in 1940. The US Army Artillery and Technical Directorate needed a rocket powder charge to accelerate the fall of aerial bombs, which, as you know, when falling from low altitudes, do not have sufficient speed at the moment of meeting with a target, which is possessed by an artillery shell of the same caliber. As a result, an aerial bomb dropped from a low altitude has a low penetration capacity; with an increase in the bombing altitude, the accuracy of the bomb hitting the target is lost. Therefore, it seemed logical to supply the aerial bomb with a rocket charge in order to maintain the accuracy of the bombing and get a high speed of meeting with the target. The rocket booster intended for this was created in the late spring of 1941, but in practice such bombs were never used.
The propellant charge in this rocket booster was a two-base propellant, which consisted of about 60% nitrocellulose and 40% nitroglycerin with a small amount of diphenylamine added as a stabilizer. This gunpowder is similar to the English rocket cordite, but the method of making it in America was very different.
The American method can be called mortar-pressing and it boils down to the following: the constituent parts of the powder are prepared separately, and then combined in the presence of a rapidly evaporating solvent. This forms a thick layer of darkish paste, which is then easily rolled into sheets for gelatinization. After that, the sheets are cut lengthwise into narrow strips and these strips are pressed. This process for the production of two-base gunpowder is considered safer than the English method.
The Germans were also familiar with dibasic gunpowders for a long time, but when Germany began to develop them closely, it was decided not to use nitroglycerin on the grounds that glycerin is extracted from fats, and in the event of a prolonged war, Germany will experience an acute shortage of them. Whatever the real reason, the Germans replaced nitroglycerin with a liquid known to chemists as diethylene glycol dinitrate. This liquid is less sensitive than nitroglycerin and therefore safer to handle, but has a greater gelling capacity than nitroglycerin.
In Germany, as in other countries, there was a constant need for ever larger rocket powder charges, larger rockets and larger launch rockets for aircraft. In America this led to the emergence of the so-called galsite fuels, and in Germany to the invention of the "giessling pulver" - a compound that is interesting in many respects. It was a special paste of nitrocellulose and diethylene glycol dinitrate with some diphenylamine and carbamite. This raw paste was crushed and gradually added to the molten trinitrotoluene in the bath with constant stirring of the mixture. The final composition of the gunpowder prepared in this way is given below.
Then the mixture in a hot state entered a vacuum, where air and water were removed from it. Thereafter, it was poured into steel molds and subjected to slow and controlled cooling for 24-48 hours. The pouring into molds made it possible to produce extremely large charges. Some experimental charges were up to 100 cm long and over 50 cm in diameter.
In 1942, Russian newspapers published the first photographs of strange German weapons captured on the Russian front. It had six short barrels about 1.5 m long, which were mounted on a light modified carriage of a 37-mm anti-tank gun and resembled the drum of an old Colt revolver. This somewhat strange system was a new German rocket weapon. Officially, it was called "Nebelwerfer-41", that is, "gas cannon", or a 1941 sample smoke launcher. The title indicated that given weapon was originally intended to be used as a chemical mortar to create smoke screens. However, reports from the front indicated that this weapon was used as a mortar for firing high-explosive fragmentation mines. Later, chemical shells for this weapon were also captured, confirming its original purpose.
Fig. 29. German missiles during the Second World War.
Above is the Nebelwerfer-41 rocket;
in the center, a larger version of the Nebelwerfer rocket;
below - rocket "Wurfgeret"
The total length of the projectile slightly exceeded 100 cm (Fig. 29), and its total weight was 36 kg. The powder charge was placed in the head and consisted of seven sticks of smokeless powder, each 400 mm long and 40 mm in diameter with a hole in the center with a diameter of 6.35 mm. The powder charge weighed about 6 kg. The projectile had a caliber of 15 cm. The launch time of all six barrels was, according to reports from the front, an average of 6 seconds, but the German manuals indicated a much lower rate of fire. The maximum firing range slightly exceeded 5000 m. The accuracy of fire was good, but, of course, it was inferior to the accuracy of fire of artillery guns of the same caliber.
The main disadvantage of the Nebelwerfer was that it strongly unmasked itself when fired; the flame of a rocket powder charge, escaping through the open breech of the launch tubes, reached 12 m in length and was extremely bright. The active part of the rocket's trajectory was 140 m, and even in the daytime, when the light from the rocket engine torch was not so noticeable, when it was launched, a large cloud of dust rose up, unmasking the firing position.
About a year after the appearance of the 15-cm "Nebelwerfer", a larger 21 cm rocket launcher with a slightly modified design was created. In the projectile of this mortar, a rocket powder charge was placed in the tail section. Instead of tubular bombs, the projectile had one large powder charge weighing 6.6 kg, 413 mm long and almost 130 mm in diameter. On the peripheral part of the charge, there were eight grooves and eight longitudinal channels in a circle, as well as one central axial channel. Below is the weight composition of this charge.
The firing range of this heavier mortar exceeded the firing range of the 15-cm Nebelwerfer by about 1000 m.
For the new projectile, several types of launchers were created. One was similar to the first Nebelwerfer, but had only five launch tubes, also located in a circle. There was also another launcher, in which five launch tubes were placed in a row. Then a launcher appeared on a railway platform, with two rows of tubes, five in each row.
By this time, a fundamentally new rocket system was created, called "Schweres Wurfgeret" (heavy throwing device).
This weapon used a 21-cm projectile jet engine in combination with a 32-cm warhead filled with a mixture of oil and gasoline (about 42 liters). The whole projectile looked like a battle club of ancient heroes and weighed over 90 kg.
"Wurfgeret" began to enter the troops with separate shells, in a special package that served as a launcher. This packing frame was tilted and the Wurfgeret was ready for launch. A heavy incendiary "bomb", propelled by its own engine, could fly over a distance of 1800 m.
Later, several such 32-cm shells were found, marked with yellow crosses at the head; with this sign the Germans designated mustard gas. But when the shells found were opened by specialists from the chemical service, they also contained a mixture of oil and gasoline.
The launching of missiles from the packing frames was quite satisfactory in terms of accuracy only at test ranges; on the battlefield, however, such shells were ineffective. Then the Germans put together six frames in two rows (three in each row) and installed them on a gun carriage, hoping in this way to improve the accuracy of fire and ensure its greater massing. Around the same time, a smaller version of the "Wurfgeret" was created with a warhead 28 cm in diameter, stuffed with high explosives.
In addition to the Nebelwerfer and Wurfgeret, the Germans had 8 cm aircraft missiles and several samples of 8.6 cm illuminating rockets. We will not touch on their device, but instead consider another missile, which, in my opinion, was very original design. This is a 21.4 cm R-LG flare. It was developed by the laboratories of the main command of the Navy in conjunction with the firm "Rheinmetall-Borzig" (Dusseldorf).
The rocket resembled an artillery shell and had a length of about 1 m. The powder charge was made in the form of one thick-walled tubular checker 50 cm long with an outer diameter of 20 cm and an inner diameter of 10 cm. Inside this wide channel was a metal tube with a lighting charge and a parachute. Maximum height the missile's flight was approximately 5000 m, the maximum horizontal range was 7500 m. It was assumed that this missile would be able to carry a high-explosive fragmentation charge in the warhead. The development of the rocket was completed only at the time of Germany's surrender, and it was not put into production.
The Russians used jet weapons extensively from the very beginning of the war, but most of their systems were highly classified. The scale of the use of missiles can be judged at least by the huge number of missiles that were launched against Paulus's army surrounded at Stalingrad. The launchers used there were of two types: some strongly resembled Congreve's launchers - wide stepladders installed directly on the ground, others were mounted on cars.
A very original Russian system was the box-like trigger, which the Germans called the "Stalinist organ." It consisted of 48 guides for launching 8.2 cm missiles, which were launched at very short intervals, that is, practically in a salvo. In the future, the Russians organized the mass production of 13.2-cm and 30-cm missiles, but information about them is kept in deep secrecy.
In Japan, missile development began in 1935, but it was slow and uncertain. It was led by Lieutenant Commander Kumao Hino. The general impression that one gets when reading various departmental Japanese reports boils down to the fact that the higher-ranking Japanese headquarters definitely did not want to interfere with the development of missiles, but did not show any interest in it either. The appropriations were small, and little material resources were released. It is known, however, that the Japanese had some achievements. So, they created their own, very original rocket solid fuel, the weight composition of which is shown below.
Potassium sulfate - intended to slow down the burning rate. By the time it became obvious that Japan was losing the war, someone had learned that Japanese military warehouses were great amount 250-kg high-explosive aviation bombs, for the delivery of which there are not enough aircraft. These bombs were converted into rockets by attaching a powder rocket motor to the tail of the bomb. The shells were fired from inclined wooden or iron chutes and had a maximum flight range of 4800 m. Other aerial bombs were also "adapted" in a similar way, and even artillery shells(see annex II).
Great research work in the field of combat missiles was carried out in England as well. The overall management was carried out by Alvin Crowe, chief of the technical service of the Ministry of Supply. Albin Crowe spoke about much of what was done in this area during the war years in a lecture held on November 21, 1947 at the Institute of Mechanical Engineers; I received a printed copy of this lecture from the English Interplanetary Society, and I will allow myself to quote here some excerpts from it.
“Reports,” said Crowe, “which were received by the British government in 1934 about the German work on missiles, made the War Department seriously consider the need to develop missiles in England. The first meeting to discuss this issue was convened in December 1934, and in April 1935, the research department of the Woolwich Arsenal was asked to draw up a work program. It was decided that, first of all, it was necessary to try to create an anti-aircraft missile, equivalent in power to the projectile of a British three-inch anti-aircraft gun. This led to the development of a 5 cm anti-aircraft missile, prototypes of which were soon manufactured and tested.
“The results of the first experiments in the spring and summer of 1937,” Crowe continued, “were encouraging; the rockets seemed quite reliable, but with the onset of the cold winter of 1937/38, it became obvious that the quality of the plastic combustion chamber created for this type of rockets was unsatisfactory.
About a year after the development of a 5-cm rocket, it became necessary to create an even larger and powerful rocket with characteristics approaching the characteristics of the new 94-mm anti-aircraft gun, which was supposed to enter service ... In this regard, the development of a 76-mm rocket began urgently, which was completed by the fall of 1938, and was already subjected to field tests the following spring. During the winter of 1938/39, about 2,500 launches were carried out in Jamaica under the missile ballistic test program.
The results turned out to be unacceptable for the imperial general staff, as the characteristics were lower than required, and in the accuracy of shooting new rocket seriously inferior to the 94-mm anti-aircraft gun. Nevertheless, the development of this missile in order to improve its accuracy continued until the beginning of the war.
Four months after the start of the war, it was decided that even such weapons that did not have sufficient firing accuracy would still find use, in connection with which an order was given to launch the 76-mm rocket into production. By that time, a launcher for this rocket was also created. During 1940-1941, several thousand of these installations were manufactured, intended for the defense of the most important facilities - the largest military factories and railway supply points. In November 1941, a twin launcher was created on the model of a single one. Later, multiple launch launchers appeared, providing batteries of 76-mm missiles with massive firing with volleys of 128 missiles. An even later step was the development of a 127mm rocket for the ground forces; in the manual to her it was said that she can carry a warhead weighing 13.5 kg at a distance of 3 to 6 km.
As already mentioned, the United States began research work in the field of military missiles in 1940. Despite the fact that the Americans were working on their own, they were familiar with the English missile models, so they could easily avoid any mistake made at Woolwich. The history of the development of American rocketry has already been told by people who are more knowledgeable in this matter, that is, those who led and led this work. I will limit myself only to a description of some technical issues and show how they were solved by American engineers.
Obviously, the invention of a high-quality powder rocket charge did not solve the whole problem; it was necessary to make sure that when it was used as a propulsion system, the rocket would provide a uniform thrust, and this just could not be achieved in a rocket on ordinary black powder. In such a rocket, the thrust almost suddenly and very quickly increases to a certain value, say, up to 7 kg, and remains at this level for a quarter of a second or so, then it also quickly drops, albeit up to 0.5 kg, and remains at this level for for another 1-2 seconds. The designers wanted a rocket that would quickly develop a certain thrust, keep it for some time and then would stop working. The curve in the graph of the change in thrust over time for such a rocket was supposed to be similar to the profile of a long, flat building with sloping walls (the so-called flat-top curve).
Such a thrust curve can be obtained only if the outflowing gases of the rocket engine are constant in relation to both the outflow velocity and the volume (mass) throughout its operation. Therefore, it was necessary to get a checker of gunpowder that would burn exactly. To understand what this is about, imagine that your checker is in the shape of a ball and only burns on the surface. As this ball burns out, its surface gets smaller and smaller. Therefore, the amount of generated gas also decreases, and the thrust curve goes down.This problem is further complicated by the fact that combustion occurs in a closed space that has only one outlet - a nozzle, and therefore any increase in pressure in the combustion chamber leads to a change in the combustion rate of the rocket charge.
One of the most commonly used solutions to this problem is to shape the rocket charge into a thick-walled tube that burns both "inward" (reducing the burning surface) and "from the inside" (increasing the burning surface). Thus, both processes must equalize the amount of emitted gases during the entire combustion process. But such combustion cannot be achieved in a powder rocket charge, which adheres tightly to the walls of the rocket; it must be kept suspended (fig. 30).
Fig. 30. Solid propellant rockets.
Above - a rocket with an armored powder checker;
below is a rocket with a powder check burning over the entire surface
In England, this was understood at the very beginning of work on powder engines. The British called such a charge "free". Researchers in America decided in their own way and called a similar charge "a checker with combustion over the entire surface." For a better understanding of the essence of the issue, let us dwell on the concepts of "checker", "wall thickness" and "lattice". A powder checker is a piece of a powder charge of any shape and size. Now there are checkers 1 m long and weighing up to 500 g for each inch of their length (200 g / cm). Every checker has a certain diameter, but it is not it main characteristic; Since checkers are usually made hollow, their wall thickness is just as important as their diameter. Its maximum thickness is taken as the wall thickness of a tubular block. A lattice is a device that holds the checker in a certain position.
An excellent example of simplicity and performance is the modern 127-mm solid-propellant aircraft rocket known as the Holy Moses. In fig. 31 depicts the three main parts of this rocket: the warhead, the rocket part (rocket engine) and the tail with the stabilizer.
Fig. 31. Holy Moses 127-mm aircraft missile
The powder checker in this rocket has a cruciform cross-section with very thick walls, which makes it very convenient for mass production. This shape of the checker section provides even combustion with a slight deviation in the amount of generated gases. In order to obtain the required burning rate, some parts of the checker can be armored with plastic strips to restrict combustion. In very long checkers, it is advisable to book only that part of the checker that is closer to the nozzle. This is to ensure that too many gases do not build up near the nozzle, which can block the gases emitted at the front of the engine and thus rupture the engine.
For some time, researchers have been struggling to solve a very curious problem. It is known that checkers made of two-base gunpowder are not always perfect. They can, for example, have internal voids that lead to the same negative consequences as cracks in black corokh checkers. Finding such voids was not easy, especially since the substance used to stabilize the combustion made the powder charge darken as it ages. Therefore, the message was greeted with great joy that the checkers can be made translucent with the help of carbamite. These checkers were easier to check, but on tests it turned out that every second charge explodes the engine. Dark checkers, which may have had large voids and defects, resulted in fewer explosions than translucent ones. A careful study showed that when the translucent checker burns, some unknown process occurs, which was called "termite cracking", because the partially burnt checkers looked like they had been eaten by termites.
A whole series of studies had to be done to find out what was going on in these checkers. It turned out that when the checker burned, not only heat, but also light energy was released, which, penetrating in the form of rays into the transparent checker, was absorbed by microscopic dust particles embedded in the gunpowder. By absorbing the rays, these particles were heated to such an extent that they ignited the gunpowder next to them. As a result, local combustion centers were formed, which led to the characteristic "cracking" of gunpowder, accompanied by explosions. It is due to these circumstances that currently all checkers are black.
After the problems of the size of the checker, the thickness of its walls, the diameter of the nozzle and other issues related to the engine were solved, another problem arose, the problem of stabilizing the rocket in flight. Previous practice has shown that there are two ways to stabilize a missile. One path was suggested by an ancient arrow, the other, more modern, by a rifle bullet. When applied to rockets, these methods can be called aerodynamic stabilization and rotation stabilization, respectively. Aerodynamic stabilization requires the creation of special devices - stabilizers in the tail of the rocket and depends on the speed of the rocket in the active section of the trajectory.
Rotational stabilization of rockets, pioneered by Gale in the 19th century, may be independent of rocket speed if the energy from the exhaust gases is used to create torque. The latter is achieved by one of two methods: the use of "gas rudders" in the flow of outflowing gases or the creation of several nozzles located around the circumference of the rocket chamber with a slight inclination (the Germans used this method in the Nebelwerfer projectile). The second method is the best, as gas rudders result in a loss of engine power.
A study of the effect of rotational momentum on missile flight accuracy was carried out by the US National Defense Research Committee's department in charge of the development of rocket artillery weapons. The research method was proposed by R. Mallin, who at that time was engaged in designing rockets for Bell Telephone Laboratories. His idea was to launch a rocket without any stabilizers from a rotating launch tube. This made it possible to test the same rocket at different rotational moments. The proposal was immediately accepted and a special launcher was built, consisting of a launch tube mounted on large ball bearings placed in a fixed tube. The entire installation had vertical and horizontal guidance mechanisms, like a conventional gun. The rotation of the inner launch tube was provided by an electric motor with a power of 1.5 liters. from.; it could rotate at 800, 1400 and 2400 rpm.
As a result of the experiments, it was found that even at moderate rotational speeds, a significant reduction in missile dispersion is achieved and that rotational speed is not a critical factor in stability. The dispersion of non-rotating standard missiles was 0-39 goniometer, that is, at a distance of 1000 m, such a rocket deflected by 39 m, and when firing missiles rotating at 800, 1400 and 2400 rpm, the dispersion decreased to 0-13, 0- 11 and 0-9 divisions of a protractor. To study the effect of rotational motion on other missiles, which had a very large dispersion, 25 such launches were carried out at a launch tube rotation speed of the order of 2400 rpm. The scattering was 0-13 goniometer. When the same missiles were launched from a 3.3 m long non-rotating launch tube, dispersion increased to 0-78
However, only a few American rotating missiles have been used on the battlefield (see Appendix II). Most of the American missiles during the Second World War were stabilized with the help of aerodynamic stabilizers. The projectile of the Bazooka anti-tank gun was very common among these missiles. The first Bazooka missiles had significant design flaws. There were frequent barrel bursts when firing on hot days, but after the charge was reduced it worked well on hot and warm weather, but on cold days he still refused. When the charge, which worked well at all temperatures, was finally worked out, there were complaints that the launch tube was too long and inconvenient for use in the forest and on rough terrain. But the launch tube had to be long, since it was necessary that the entire powder charge burned out before the rocket left the tube, otherwise the rocket engine torch could burn the gunner's face. This particular problem was later solved very simply by creating a folding launch tube.
For the first time on the battlefield "Bazooka" was used in North Africa... When, in early 1943, Major General L. Campbell announced the existence of this weapon among the allies and explained that a small rocket weighing only a few kilograms could destroy a tank, many thought that its effectiveness was due to the high velocity of the rocket projectile. In reality, the Bazooka rocket moves very slowly; it can be seen all along the trajectory from the launch tube to the target. The secret of high penetration had nothing to do with the fact that the Bazooka was powered by a rocket engine; he was hiding in the pointed warhead of the rocket, where the shaped charge was placed.
This charge was invented by the American explosives specialist, Professor Charles Munro. In 1887, while experimenting with explosives, Munro noticed a completely new and startling phenomenon. One of the explosives he tested was a pyroxylin disk engraved with the letters and numbers “USN 1884” indicating the place and time of its manufacture. Munro detonated this disk of pyroxylin next to a heavy armored plate. As he expected, the damage to the armored plate was minor, but the letters and numbers "USN 1884" were carved into the metal! Nothing like this has ever been observed. This strange phenomenon could only be explained by the fact that the explosive charge did not adhere tightly to the metal in the places where letters and numbers were carved. Munro concluded that the combination of a small airspace and a tight metal explosive around the airspace was likely to be the cause. To test his guess, he took a bunch of dynamite sticks and tied them tightly together, and pulled several central sticks inward by 2 cm. The resulting charge easily punched a hole in the thick wall of the bank safe. In 1888, Professor Munro wrote several articles about his discovery, and since then this phenomenon has been called the "Munro effect", which was explained by the focusing effect of the explosion products of the charge.
When viewed from the side, the explosion of a shaped charge is similar to the explosion of any other charge: the explosion energy spreads evenly in all directions, but inside the air cavity, the gases released by the explosion are focused, that is, they are collected in a narrow stream with a high penetrating power (Fig. 32).
Fig. 32. Munro's shaped charge of the American M9A1 grenade (arrows show the direction of the explosion)
Military research on shaped charges was not carried out until World War II, when the metal lining of the shaped charge funnel was created. If the Munro effect manifested itself as the action of a high-intensity jet of incandescent gases ejected in one direction, then it was quite clear that the penetrating power of this jet could be increased if its mass was increased in some way. It was assumed that the metal layer covering the funnel would be torn apart by the explosion into small fragments, which would increase the mass of the gases. Soon this assumption was confirmed experimentally, and zinc and steel were recognized as the most effective facing material for the funnel.
The Munroe effect depends not only on the presence of a cavity in the explosive and metal lining, but also on the distance between the charge and the target at the moment of the explosion. This distance should be equal to several centimeters. For this reason, the shaped charge at high meeting speeds becomes ineffective, since it takes some time for the fuse to operate and the charge to explode. The Bazooka rocket was quite suitable in speed for a shaped charge. Apart from improved versions of the same Bazooka missile, the other American missile equipped with a shaped charge was the Ram missile, which was hastily developed for the Korean War.
The heavier American missiles during the Second World War did not have shaped charges, since they were intended to fight not against tanks, but against enemy manpower. This includes rockets with a caliber of 114 mm and 183 mm. The first one weighed about 17 kg, had almost the same destructive force, like a 105-mm howitzer projectile, and was serviced by one person. It was released along with a packing tube, which simultaneously served as her and the launcher. A tripod was attached to the tube, similar to a camera tripod. The entire system weighed about 23 kg.
Rockets with a caliber of 114 mm and 183 mm were mounted on installations on the decks of special missile-carrying ships; at the same time, fire control was carried out from a safe shelter below deck. One missile-carrying ship within a few minutes could throw out as much steel and explosives as the gun turrets of three battleships. The massive use of missiles made possible successful breakthroughs of coastal defenses and the landing of amphibious assault forces. Thus, the invasion of southern France was carried out after the massive use of up to 40,000 missiles.
To support the ground forces, special "rocket" tanks were created. On the turret of the Sherman M-4 tank, 60 launch tubes for 114-mm missiles were installed in four tiers. This installation was named "Calliope", it rotated with the turret of the tank. The hinge rod, which connected the unit to the 75-mm turret gun, made it possible to carry out vertical aiming using the vertical aiming gun mechanism. The electrical launching device, developed by Western Electric, made it possible to launch rockets at very short intervals.
The secret device throughout the war was the M-10 anti-submarine missile launcher, known as the Hedgehog. It was developed in England, but later transferred to the United States, where the Navy specialists significantly improved it. The installation had 24 heavy rockets that fired within 2.5 seconds. The missiles fell in the area of the alleged location of the enemy submarine and plunged into the water with the warhead down. The charges of these missiles were not ordinary depth charges, they exploded only when they met a target, and not when they reached a certain depth. Therefore, the sound of an underwater explosion was an indicator that Submarine amazed.
However, the largest American missile during the Second World War was the Tiny Tim aircraft missile, designed to engage targets beyond the reach of conventional artillery. Outwardly, it resembled an aviation naval torpedo and had a length of 3 m and a diameter of 30 cm; in the starting position, she weighed 580 kg. Powder rocket charge consisted of four cruciform checkers with a total weight of up to 66 kg. The warhead of the Tiny Tim rocket weighed 268 kg and carried about 68 kg of TNT.
The first experimental launches of the Tiny Tim rocket from an airplane were carried out using a device extending from the bomb bay; when launched from fighters, the rocket was dropped on a lanyard.
During one of the first tests, at the end of August 1944, an accident occurred. Immediately after the launch of the Tiny Tim rocket, the aircraft from which the launch was carried out went into a dive and crashed. At the same time, the pilot, Lieutenant Armitage, was also killed, after whom the airfield at the missile test station in Inyokerne (California) is named. Investigation into the causes of the crash showed that the tail of the aircraft was badly damaged by the rocket igniter. It was proposed to significantly reduce the power of the igniter, as well as increase the length of the cord. Since then, there have been no accidents with missile launches.
During World War II, the Tiny Tim missile was used against the Japanese on the island of Okinawa. But then it was not possible to establish the effectiveness of the missile bombardment, because the missiles were used in conjunction with many other means of destruction.
The beginning of the development of anti-aircraft missiles dates back to this time. These rockets differ in that they need an accelerator to provide as much initial impulse as possible at launch. Naturally, this is achieved by maximizing the accelerator charge. Originally anti-aircraft guided projectiles the shape and appearance of a jet plane was given. But, in order to launch these projectiles and put them on the trajectory, a powerful rocket booster or an expensive and too bulky catapult was needed. Unfortunately, the launch rockets manufactured at that time were comparatively small and low-powered. To ensure the takeoff of a fighter plane, two or four such missiles were required, and for a heavy bomber to take off, several dozen such missiles were needed. Therefore, the development of heavy, powerful accelerators was taken up not only by the creators of guided anti-aircraft missiles, but also by aviation industrial firms.
Fuel chemists, of course, were well aware of all the possibilities of then-known accelerator fuels. Their main problem in this matter was not so much the search for the actual fuel, that is, the substance to be burned, as the selection of an oxidizer - a substance that provides oxygen necessary for combustion. All solid oxidizers known at that time were divided into two groups, each of which contained a large number of substances distinguished by their advantages and disadvantages.
The first group consisted of nitrates, of which potassium nitrate (KMO 3) was most known in pyrotechnic practice. Almost 40% of its weight is oxygen released during combustion. However, the products of combustion with this oxidizer consist mainly of fumes, which creates great difficulties when working with it. The next in this group was sodium nitrate (NaNO 3), which gives off even more oxygen (about 47%), but also produces a lot of smoke and, in addition, has a number of disadvantages. The third oxidizing agent, ammonium nitrate (NH 4 NO 3), does not form any solid products during combustion, but releases only 20% oxygen, since part of the oxygen goes to combine with hydrogen of the same molecule. In addition, with a large increase in temperature (above 32 ° C), the volume of ammonium nitrate changes greatly, which seems unsafe.
The second group included perchlorates. At first glance, these substances seem to be more effective than nitrates, since they release on average more than 50% (by weight) oxygen. Thus, magnesium perchlorate (MgCl0 4) releases 57.2% oxygen. But chemists rejected this substance because of its extremely high hygroscopicity. The next in the amount of oxygen released (52%) is sodium perchlorate (NaCl0 4), also a very hygroscopic compound, which, when burned, emits a solid - table salt... Another oxidizing agent of this group, potassium perchlorate (KClO 4), gives almost 46% oxygen, but, like sodium perchlorate, forms a solid residue, potassium chloride (KCl). The last in the group is ammonium perchlorate (NH 4 Cl0 4); it releases up to 34% oxygen, does not change volume like ammonium nitrate, and does not emit any solids with combustion products. But one of the combustion products of ammonium perchlorate is hydrogen chloride (HCl) - extremely toxic and very active substance which forms fog in damp air.
Of all the oxidants listed, only potassium perchlorate can be used in a rocket engine, and it has indeed been used as a fuel component by the Guggenheim Aviation Laboratory of the California Institute of Technology (abbreviated as GALCIT).
However, we forgot about another group of chemicals with high oxidizing properties - the so-called picrates, which are based on picric acid. This acid can be explosive and, in addition, it is quite toxic. Its full name is trinitrophenol (HO C 6 H 2 (NO 2) 3). Chemists classify it as a typical nitro compounds of the aromatic series, and the military call it liddite or melinite. Very pure picric acid in itself is quite safe, but it easily forms some salts when reacting with metals - picrates, which are extremely sensitive to friction or heat. Picrates of heavy metals, especially lead, detonate at the slightest shake. Light metal picrates are easier to handle; For a long time already known such piquant powders as Brougeres gunpowder and Designol's gunpowder, which were used both for civil explosive works and for military purposes. Gunpowder Brougeres consisted of 54% ammonium picrate, 45% potassium nitrate and 1% inert substances. Designol's gunpowder included potassium picrate, potassium nitrate and charcoal.
Currently, a rocket powder mixture is used that closely resembles Brougeres gunpowder, which consists of ammonium picrate (40-70%), potassium nitrate (20-50%) and a solid additive.
However, despite the certain promise of picrate propellants, the old two-base Nobel propellants, which are now manufactured not in the form of pressed sticks, but in the form of cast propellant charges, have become more common. Pressed Nobel checkers usually included 50-60% nitrocellulose, 30-45% nitroglycerin and 1-10% of other substances, while cast charges, along with nitrocellulose (45-55%) and nitroglycerin (25-40%), contain up to 12 -22% plasticizer and about 1-2% various special additives.
Replacing pressing with casting made it possible to create charges more than 30 cm thick and over 180 cm long, releasing all the energy contained in them within 2.5-3 seconds and thereby creating a huge initial impulse. Large cast powder charges are surrounded by a layer of plastic that adheres tightly to the walls of the rocket motor housing.
One of such large accelerators is shown in section in Fig. 33. In this example, the front plate presses the charge with a powerful spring. This allows you to fix the position of the charge and have a small space to compensate for the thermal expansion of the charge at the beginning of combustion. The charge ignites from the front, and combustion develops from the central channel to the periphery of the charge. By shaping the central channel, the internal pressure can be controlled. The cross-shaped checker discussed above, for example, burns in such a way that the internal pressure is as high as possible at the moment of ignition of the charge, while the thick-walled tubular checker theoretically provides a constant pressure in the combustion chamber during the entire period of engine operation; such combustion is called constant draft combustion. If the pressure in the combustion chamber rises from the moment of ignition and increases until the entire charge is burned out, combustion with an increase in thrust is said to take place. Such combustion is most typical for a checker made in the form of a rod with several longitudinal channels; it is less inherent in such checkers, which fit tightly to the walls of the engine housing and have only one central channel. If the latter is not round, but star-shaped, an interesting phenomenon occurs: the charge burns with a slight increase in thrust during the first quarter of a second, then, for 2 seconds, burns with a decrease in thrust, after which the thrust increases again. In addition, the star-shaped cross-section of the central channel places very little demand on the strength of the housing and thus allows its weight to be reduced.
Fig. 33. Solid fuel accelerator
These boosters are used to launch large guided projectiles, such as the Matador projectiles. There have also been several attempts to use them on experimental manned fighter planes. In addition, they tried to put rocket boosters on special rocket sleds and carts to test the effect of large accelerations and decelerations on the human body. Similar boosters have been tested on anti-aircraft missiles, leading to the creation of an entirely new type of research rockets, which are discussed in subsequent chapters of the book. And, finally, these heavy cast charges made it possible to create new surface-to-surface missiles capable of carrying a heavy warhead, including a nuclear one, at a distance corresponding to the firing range of the most long-range artillery.
Fig. 34. Rocket "Honest John" and its flight paths
The rocket I mean is called Honest John (Fig. 34). This thoroughly tested and completely reliable system, officially called the M-31 artillery rocket, has an XM-289 type launcher with an elevation angle of about 45 °. In appearance, the Honest John resembles a huge Bazooka missile, mainly due to its massive, pointed warhead. On October 4, 1956, during a demonstration at the Aberdeen Proving Ground, one of the Honest John missiles covered a distance of 20 800 m, and the second covered 20 600 m.
The characteristic feature of the Honest John rocket is that it has no guidance system; aiming is carried out, like an artillery gun, by changing the elevation angle of the launcher. Since all propellants burn at different speeds, depending largely on the ambient temperature, the results of rockets launched are not exactly the same. To somehow reduce the temperature effect of the ambient air, the Honest John rocket is equipped with special thermoelectric blankets. At low temperatures, these blankets maintain the optimum temperature of the powder charge. At present, a smaller version of the Honest John rocket has been created - the so-called Little John XM-47. This rocket has a caliber of 318 mm.
Notes:
An ancient Greek measure of length that fluctuated depending on the terrain within the range of 150-190 m. (Ed.)
The full title of this book looks like this: “The Star Messenger, announcing great and amazing spectacles and bringing them to the attention of philosophers and astronomers, which spectacles were observed by Galileo Galilei with the help of his recently invented telescope on the face of the moon, in countless fixed stars, in the Milky Way , in foggy stars, especially when observing four planets orbiting Jupiter at different intervals with amazing speed, planets that until recently were unknown to anyone and which the author recently discovered first and decided to call the Medicean luminaries. " - (Author's note)
See Eberhardt O, Freier Fall, Wurf und SchuB, Berlin, 1928.
Lehmano E, A. Zeppelin, Longmans Green. New York, 1937, p. 103-104.
In the domestic industry and literature, this substance is known under the name "centralite". (Ed.)
It was later found that this factor can be easily freed from. The Philipps Petroleum Rocket Fuel Branch has developed a solid accelerator fuel consisting of carbon black, synthetic rubber and some additives with ammonium nitrate as an oxidizing agent. This fuel is highly resistant to large temperature fluctuations, but emits a small amount of smoke when burning. (Author's note)
This fuel consisted of 70-78% KClO 4 and 22-30% asphalt with a small addition of asphalt oil. (Author's note).
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