It has long been known that survivability in battle can be ensured not only by good protection, but also by camouflage. For a long time, too little attention was paid to camouflage in aviation. In fact, it all came down to only a special camouflage color: the upper surfaces of the aircraft are painted “camouflage”, and the lower surfaces are painted blue, to match the color of the sky
Discovery of physicist Peter Ufimtsev
About thirty years ago, while leafing through a popular scientific and technical magazine, American intelligence officers came across an article by Russian physicist Pyotr Ufimtsev, which stated that wing-type aircraft made of certain materials, cut and painted in a special way, are practically invisible to radar. .
Stealth American stealth aircraft, invented by a Russian scientist. "Dead end" branch of aviation.
Construction and testing of the aircraft
The article was of great interest to American military specialists, and the United States decided to build and test such an aircraft.
There were opportunities for this. Then the Pentagon - the US Department of Defense - was developing a program to create a new generation of aircraft - a high-altitude reconnaissance aircraft and a high-altitude interceptor, which were intended to be inaccessible to enemy detection and destruction means. So in the mid-1970s, the US Air Force received a first-class reconnaissance aircraft SR-71, which They were distinguished by an unusual aerodynamic shape and special painting, made according to Ufimtsev’s “recipes” and reducing the radar visibility of the aircraft.
Inspired by their success, the Americans moved on and began to develop new types of stealth aircraft based on the ideas of the Russian physicist. The project was called “stealth” (from the English word “stealth” - quietly, furtively).
Creation of a stealth plane
Attempts to create a “completely invisible aircraft” were unsuccessful for a long time. Only twenty years ago, the United States showed the world a miracle of military technology that looked like a bat or an alien ship. Two modifications of the “stealth” aircraft were manufactured: the F-117 fighter-bomber and the B-2 heavy strategic bomber, which were used in the war against Iraq. A little later, the F-22 stealth fighter entered service. Externally, the F-117 is similar to a flying wing with a span of 13.2 m. But in addition to the specially selected shape, its entire structure was developed with the maximum possible use of radar-absorbing materials.
They reduce the level of reflected signals, which, moreover, are not reflected back, as from ordinary surfaces, but up and down in narrow sectors. With the help of special exhaust nozzles and the supply of ambient air, the intensity of the infrared radiation of the engine jet stream is significantly reduced, that is, the enemy’s “thermal” sensors will also not detect this aircraft.
The “invisible” even has a special communication system - a laser one, which is almost impossible to find direction. True, the F-117, to put it mildly, does not shine with its flight performance qualities. You can’t do modern aerobatics on it - that’s the price to pay for “invisibility.”
Stealth technology
All “stealth” technology was designed for the enemy to use centimeter-range locators, for which American “stealth” aircraft actually become inconspicuous. However, in Russia, and the air defense forces of other countries today have meter-range locators, for which it does not matter Is it a stealth plane or a regular plane?
The news of the invisibility of “stealth” devices for only one type of locator caused a real scandal in the US government. After all, billions were spent on the development of stealth aircraft, but it turned out that the effectiveness of new aircraft in combat may be inferior even to older machines. It turned out that the Americans’ technological breakthrough in the production of “stealth” aircraft was associated with the emigration to the USA of Ufimtsev, who was involved in the creation of invisible
Ufimtsev did the same thing for many years in the USSR. And not only him.
At least two Soviet design bureaus built and tested stealth aircraft of various types. The conclusion of the authoritative commissions was as follows:
1) the stealth aircraft, manufactured according to Ufimtsev’s ideas, due to its shape has low speed and maneuverability - essentially it is a hang glider, poorly adapted for combat maneuvers and incapable of aerobatics;
2) the aircraft can be detected visually and by special high-frequency radars; in addition, when the bomb bays are opened and in some flight modes, it is visible to conventional radars and after “notching” it can be easily shot down;
3) the cost of the aircraft is prohibitively high.
Conclusion: the construction of such aircraft is impractical
; Moreover, this type of aircraft is “a dead-end branch in the development of military aviation.”
Therefore, in the early 1980s, work on the Ufimtsevo “stealth” in the USSR was stopped. The offended designer left for the USA, where he implemented his “senseless” ideas, as time has proven, at the expense of the Americans.
Implementation of the designer’s ideas in the USA
The modern development of combat aviation has taken a different path: development of a new generation of aircraft is underway, characterized by ultra-high speed, flight altitude, maneuverability and stealth (due to these properties) for enemy air defense systems.
Stealth technology remains at the forefront of military engineering today. It revolutionized the foundation of world aviation, making airplanes the main tactical weapon on the battlefield. Stealth fighters were first introduced to the world after the sensational Operation Desert Storm. American engineers performed a miracle by releasing the F-117 aircraft into wide production. The development of new technology was carried out by Lockheed. Stealth aircraft could easily fly into any well-protected airspace and eliminate a target while remaining undetected by local radars.
Stealth technology
Engineers from the American company Lockheed made significant progress in development in the late 1970s. Previously, similar technologies were used to camouflage submarines and ground-based armored vehicles. However, an improved approach was later used to hide a large object in the airspace.
"Stealth" is an aircraft that is invisible to most radars and equipment scanning in the infrared spectrum. Conventional aviation units, falling into the range of radiating waves, are picked up by equipment. This effect is achieved due to the reflection of the radio signal from the aircraft body. The larger the scattering area, the higher the probability of detecting an object. A large bomber has an indicator of about 100, a fighter - up to 12, and an American stealth aircraft - 0.3 sq.m.
The foundation of stealth technology is considered to be two components: maximum absorption of radiation from locators by the surface of the body and reflection of waves in a direction not included in the radar search range. The solution to these problems was a special coating and angular shape of the aircraft.
Development of such an aerial object has been carried out since the early 1960s, but limited technical and financial resources did not allow the desired results to be achieved for a long time. The situation changed dramatically after a decade and a half. In 1981, the first stealth aircraft took to the skies. From that moment on, the production of the F-117 became widespread.
Pros and cons of technology
We can only say good things about the Stealth aircraft. Nevertheless, many military experts have long expressed their dissatisfaction with the innovation of American aviation. And indeed, if you look in detail, the technology had its significant drawbacks. Firstly, this concerns the cost of the aircraft. Construction of one unit cost more than half a billion dollars. Large stealth bombings were even estimated at $1.1 billion.
The next nuance was the dramatic development of radar equipment. By the early 1990s, almost all radars could, with varying degrees of probability, detect stealth aircraft. Because of this, American engineers had to constantly improve their developments.
Another disadvantage of the technology was a noticeable decrease in the flight characteristics of the stealth, since during the design the emphasis was on radar stealth. As a result, the Stealth (aircraft) was much inferior to many other air units in speed, maneuverability, and even safety.
As for the advantages, in addition to stealth, it is worth highlighting the effective counteraction to the strike threat. The fact is that not a single automated missile is capable of fixing an aircraft with sufficient accuracy.
To date, the American government continues to allocate billions of dollars for the construction of new representatives of the Stealth class.
The principle of operation of a stealth aircraft
To absorb radio radiation, a ferromagnetic coating is used, which is applied to the entire body of the object. When waves hit this surface, under the influence of microscopic magnetic particles they are redirected with an increased frequency in the direction other than the radar. Thus, the radiation energy is spent. To improve stealth properties, all equipment and accessories in the aircraft are made of carbon fiber. Also, to redirect the radio beams, it was decided to construct the body and wings from planes, without curved surfaces.
The stealth aircraft has special turbojet engines. The difference from traditional ones is the use of a diffuser in front of the compressor. This allows radiation to be reflected into the engine, thereby neutralizing it. The aircraft is also equipped with a cooling system. It forcibly reduces infrared engine noise.
Even the pilot's seat was changed to diffuse radar studies. It has a corrugated shape, like all other vertical parts of the aircraft. Moreover, the tail of the aircraft also underwent changes. As a result of modifications, it acquired a V-shaped horizontal shape.
The first stealth plane
In 1981, the advanced development of the American company Lockheed was the subsonic strike Lockheed F-117 Night Hawk codification. The aircraft was designed to quickly penetrate the enemy's tactical zone, successfully hiding from air defense systems. As a result of subsequent upgrades, technologies to counter homing missiles were introduced.
By 1990, the US Air Force had 64 F-117 units. In international codification, the aircraft was named “Night Hawk”. According to the American designation system, the invisible aircraft is assigned the letter F. Interestingly, for a long time the F-117 was considered a fighter. Nevertheless, today it is a conventional subsonic tactical-strike aircraft.
The Nighthawk was successfully used in combat operations in Panama, the Persian Gulf, Yugoslavia, and Iraq. The first losses dated back to March 1999. It was a stealth plane shot down by a S-125 missile near the Serbian settlement of Budzhanovci.
At the moment, the Nighthawk has been withdrawn from service due to a lack of funds in connection with the development of the F-22 fighter (the new Stealth aircraft).
Lockheed F-117 Specifications
The length of the aircraft is 20 m, while the wingspan exceeds 13 m. The crew includes one pilot. The F-117's weight varies from 13.4 to 23.8 tons, depending on load and fuel capacity. Initially, it was planned to reduce the nominal weight of the aircraft to 10 tons, but in the end the cooling installation required additional space. As a result, the lower part of the body had to be modified.
The package includes 2 F404 engines with a total thrust of 9700 kgf. As for flight characteristics, the maximum flight range is about 1720 km. In this case, the combat radius is 860 km. "Nighthawk" is capable of rising to a height of up to 13.7 kilometers. The driving speed is 993 km/h, in autonomous mode - 905 km/h.
Description of the invisible B-2 Spirit
This stealth aircraft was developed by the American company Northrop Gr. Today it is in active use. It is a heavy strategic bomber. Designed to destroy large tactical ground targets. Capable of breaking through dense air defense thanks to the use of Stealth technology. The cargo compartment has the ability to transport nuclear weapons. The Spirit project cost the American government $45 billion.
The bomber's crew consists of 2 people. The nominal weight of the stealth is 72 tons. At the same time, the aircraft is capable of lifting up to 100 tons of supplies and fuel into the air. All four engines are double-circuit turbojet engines. Maximum thrust - 30500 kgf. The bomber reaches speeds of up to 1010 km/h. The flight range exceeds 11 thousand km.
Standard armament includes Mk or CBU class bombs, AGM missiles and B nuclear weapons. It is currently the world's largest stealth aircraft.
Characteristics of the F-22 Raptor
The Raptor fighter is a fifth-generation multi-role aerial object. Its development was carried out by Boeing, Lockheed and GD. It is the newest and most advanced stealth fighter in the world.
The F-22 is based on the principle of striking a target with lightning speed. It is worth noting that all of the Raptor’s weapons are located in special internal compartments to reduce visibility. The fighters underwent their baptism of fire in Syria in the fall of 2014.
The F-22 can only be crewed by one person. Net weight is about 20 tons. Loading capacity varies within 10 tons. The configuration includes two engines with a power of 7400 kgf. When flying, the fighter reaches speeds of up to 2410 km/h.
Russian stealth project "Berkut"
In 1997, the first experimental carrier-based fighter Su-47 was released. Its designer was Mikhail Pogosyan. Work on the project was carried out in Russia.
The Su-47 is considered a completely strategic object, so it does not carry any weapons. Its purpose is to obtain and analyze intelligence data from well-protected enemy points. In the future, it is planned to upgrade the aircraft to a light bomber.
Crew - 1 pilot. The nominal mass of the object is 26.5 tons. Both engines are dual-circuit turbojet engines with an afterburner. The total thrust is provided at 17,500 kgf. This allows the Su-47 to reach speeds of 2,500 km/h.
Asian invisible Shenyang J-31
This Chinese stealth aircraft only entered widespread production at the end of 2012. It is a multi-role fighter of the latest generation. The world became known as "Krechet" after the international exhibition in Zhuhai.
The fighter is controlled by 1 pilot. It is worth noting that the J-31 is considered one of the smallest stealth aircraft. Its length is only 16.9 m, and its wingspan is 11.5 m. At the same time, the mass of the object is 17.5 tons. The maximum speed threshold is 2200 km/h.
« Stealth technology "brought us back to that fundamental principle of war called surprise," said John Welch, vice chief of the Air Force, shortly after the end of Operation Desert Storm. - “If you can achieve surprise, you will have a big advantage.”
The advantage claimed was convincingly demonstrated during six weeks of continuous night bombing of Baghdad stealth aircraft Lockheed F-117A. These “black ghosts” flew freely into the heart of one of the most secure airspaces in the world and, having dropped their deadly cargo, returned unharmed.
WHAT IS STEALTH TECHNOLOGY?
The technology that has enabled such significant progress did not appear suddenly. The Navy has been using the same camouflage techniques on strategic and attack submarines for more than 30 years. The Army has also long used similar technologies to reduce infrared radiation from tanks and other equipment.
The essence of stealth technology is to reduce the visibility of equipment in the radar and infrared radiation spectrum. Typically, equipment reflects radio waves that fall on it, which are picked up by the radar - this is radar signature. It is characterized by the effective scattering area (ESA) - the ability of an object to scatter an electromagnetic wave. For example, the ESR of a B-52 bomber is 100, a heavy bomber is 13-20, a conventional fighter is 3-12, and an invisible aircraft made using stealth technology is only 0.3-0.4 sq.m. Stealth technology is based on two techniques: firstly, maximum absorption of radio radiation by the surface of the aircraft body, and secondly, reflection of radio waves in such a direction that they do not return back to the radar. For this purpose, special coatings and a specific shape of the aircraft body are used.
In aviation, attempts to develop something similar to the F-117A stealth aircraft have been made for a long time. Back in 1962, Lockheed was hard at work developing the stealthy A-12 aircraft. Another aircraft of that time, the SR-71 Blackbird, implemented stealth technology in the form of special coatings and structural materials.
In the early 70s, progress in the field of computer technology and... programming gave impetus to the development of aircraft manufacturing. The software, called ECHO, allowed Lockheed to simulate various aircraft body designs on a computer and obtain their expected appearance on a radar screen without building the actual aircraft. As a result, in 1975, she built a full-scale model of the prototype F-117A stealth aircraft, the Have Blue. At the same time, the Northrop company presented its development, but after testing both models using a real radar, the Lockheed version won. In the winter of 1977, an experimental flight of Have Blue took place, after which the US Air Force immediately ordered 24 F-117A fighters, the first of which was built in June 1981, and in 1983 the aircraft was put into service.
Convinced by the example of the F-117A fighter of the technical validity and feasibility of the stealth aircraft concept, the US Air Force command commissioned Northrop to develop a new strategic bomber with extensive use of stealth technology. Design work on its creation began in 1979, and the official ceremony of presenting the new aircraft, designated B-2 Spirit, to specialists and representatives of the press took place in November 1988.
FEATURES OF THE INVISIBLE AIRCRAFT
After a brief introduction to the history of stealth aircraft, let's look at the basic principles of stealth technology that were used in their creation.
1. A special ferromagnetic coating of the aircraft body is used to absorb radar radiation. Electromagnetic radiation falling on such a coating causes microscopic particles of the magnetic material included in its composition to change their orientation with a high frequency, which is what the radiation energy is spent on. In addition, as much as possible of the aircraft itself is made from radio-absorbing composites such as carbon fiber.
2. Rounded surfaces in the body shape are almost never used. Instead, it consists of many planes that reflect radar radiation not in the opposite direction, but in different directions. For the same purpose, the sweep of the wings is increased.
3. Conventional turbojet engines are designed so that the radar can “see” a compressor with a large reflection area that reflects radiation well. According to the new technology, a special diffuser is installed in front of the compressor, the sharp top of which reflects radiation into the engine housing and thus extinguishes it.
4. The flat-shaped engine creates a jet torch with a wide angle of divergence of hot gases, which dissipates the heat flow and reduces the degree of visibility in the infrared range.
5. Both engines of the stealth aircraft are equipped with noise-reducing casings, as well as a forced cooling system that reduces infrared emissions. Some of the cold air entering through the air intakes is supplied directly to the exhaust area and, mixing with the hot reactive gases, cools them.
6. Even parts of a stealth aircraft that should be roughly vertical, such as the pilot's seat, are corrugated to dissipate radar energy.
7. The aircraft’s V-shaped tail (also called a “butterfly”) replaces two horizontal and one vertical planes of a traditional tail, which also reduces visibility.
Stealth technology also applies to other types of military aircraft. For example, in 1990, the General Dynamics AGM-129A ASM air-to-surface cruise missile with a low level of unmasking characteristics entered service with the US Air Force strategic aviation. It was developed using stealth technology and is intended to arm the B-52N, B-1B and B-2 bombers. The ACM cruise missile is close in size to the Boeing AGM-86B ALCM cruise missile.
"STEALTH TECHNOLOGY": "FOR" AND "AGAINST"
Stealth technology has long been ambiguously perceived by many military experts. One of the disadvantages of using this technology is the high price of “stealth aircraft”. The B-2 bomber is the most expensive aircraft in aviation history - $1.157 billion per unit. In addition, although American aircraft made using stealth technology are called “invisible” in the press, this is an exaggeration. They can, in principle, be detected by modern radar equipment. A radar with a powerful emitter will still detect an “invisible aircraft,” albeit from a shorter distance. For example, the S-300 complex could “see” the F-117A from a distance of 50-60 km. In addition, short-range air defense systems equipped with television-optical sighting equipment can generally capture a target via a visual channel, in which the “invisible aircraft” is as clearly visible as any other material object.
At the same time, excessive emphasis on radar stealth leads to a decrease in the aircraft’s flight qualities: it greatly loses in speed, maneuverability and flight safety. The fact is that an aircraft with such geometry and aerodynamics as the F-117A cannot stay in the air on its own and its flight requires every second adjustment using the controls. This function is performed by the computer. At least one F-117A stealth aircraft was lost due to misconfiguration of the flight control system.
A significant advantage of stealth technology, however, is that homing missiles and other automated air defense systems cannot lock on such an aircraft as a target with sufficient accuracy and, as a rule, miss.
The combat career of the “stealth aircraft” F-117A also turned out to be not entirely clear-cut. On the one hand, this aircraft quite successfully participated in five wars: the US invasion of Panama (1989), (1998), the NATO war against Yugoslavia (1999), and the Iraqi war (2003). At the same time, only one aircraft was lost in combat missions (in Yugoslavia). On the other hand, during operation, out of 64 F-117A “stealth aircraft” built, six were lost due to flight accidents - almost 10% of the total number, which, of course, is a lot. Only the most experienced pilots were put on the F-117A, but still the “stealth planes” regularly crashed. But the F-117A were withdrawn from service in 2008 not even because of this, but because of a banal lack of money for their maintenance. The freed up funds were used to purchase new F-22 multirole fighters.
Nevertheless, stealth technology continues to be used in the American aircraft industry. American fifth-generation fighters Lockheed/Boeing F-22 Raptor and Lockheed-Martin F-35 Lightning II are stealthy, although their appearance is not as exotic as that of the F-117A. These aircraft are also extremely expensive, and even a country like the United States cannot afford to build them in large numbers. A total of 184 F-22 Raptors were built before production ceased.
Russian experts have long viewed stealth technology with skepticism, although certain methods of reducing the visibility of aircraft have, of course, been introduced. However, in the latest aviation developments, visibility reduction technologies occupy an important place. New Russian aircraft: the Su-34 fighter-bomber, the MiG-35 light front-line fighter and the Su-35S heavy fighter have reduced visibility. Promising Russian aircraft: the PAK FA heavy multirole fighter and the PAK DA long-range strategic bomber are being developed as “stealth aircraft.”
Lockheed F-117 Nighthawk - American tactical bomber developed by Lockheed Martin in the late 1970s. The first production aircraft based on the use of stealth technologies.
History of the F-117
The ability to create a combat aircraft that would be invisible to enemy radars has been a military dream since the advent of air defense radars. Even during the Second World War, German aircraft designers tried to make their aircraft invisible; this work continued after the war as part of various research programs. In the 1960s, as part of a project to create a high-speed reconnaissance aircraft, some techniques were actively used, however, due to the enormous power of the engines and the speeds that literally heated the body, the aircraft did not become invisible. However, the potential was noticeable.
In 1977, the XCom experimental committee was formed at the Pentagon, whose task was to bring Stealth technology to the level of practical applicability. It was then, on the basis of developments on the SR-71, as well as the results of tests under the secret XST program, that the committee authorized the Senior Prom program (from which the ACM stealth cruise missile grew), ATB (which became a bomber), and, finally, Senior Trend, which resulted in the F-117.
Since most of the work on Senior Trend was carried out in the Skunk Works laboratories, the development contract went to the owner of the laboratories, Lockheed Martin. The requirements of the secrecy regime were extremely high, evidence of this is the name of the aircraft - the F-117 fell out of the general line of aircraft:, and so on. According to an unspoken rule, the US Air Force assigned three-digit numbers to secret aircraft.
F-117 design
The design of the aircraft is based on stealth technology. The aircraft itself is built according to the “flying wing” aerodynamic design with a V-shaped tail. Completely uncharacteristic of subsonic aircraft, a highly swept wing (67.5°) with a sharp leading edge, a wing profile outlined by straight lines, a faceted fuselage formed by flat trapezoidal and triangular panels are located in such a way relative to each other as to reflect electromagnetic waves away from the radar enemy. The flat air intakes located above the wing on both sides of the fuselage have longitudinal partitions made of radio-absorbing materials. Part of the cold air flow is separated at the entrance to the air intakes and, bypassing the engines, enters flat nozzles shielded by the wing, the lower panels of which are covered with heat-absorbing ceramic tiles, which significantly reduces the aircraft’s IR signature. The aircraft does not have external suspensions; all weapons are located inside the fuselage.
Polymer composite materials and radio-absorbing materials and coatings are widely used in the design of the aircraft; only 10% of the structure is made of metals. As a result of these measures, the effective scattering surface of the aircraft when irradiated by a radar from the front was reduced, according to some data, to 0.025 m², which is several tens of times less than the EPR of conventional aircraft of similar sizes.
Lockheed F-117 Nighthawk - the first stealth aircraft. Skyships channel video
It is worth noting that the high stealth characteristics had to be paid for with low flight characteristics. The plane is very difficult to control - a complex automatic control system was developed just so that it could remain stable in the air. Naturally, if visually detected by enemy fighters, the F-117 was doomed - its maneuverability was barely higher than that of the Shuttle. In addition, the shape of the aircraft completely excluded the possibility of breaking the sound barrier. However, when criticizing the vehicle, it is worth considering that the F-117 is a tactical bomber, not a fighter, and maneuverable combat in targeting was not envisaged for such an aircraft at all.
The weapons compartment is two-sectional, with a system of retractable beam holders. Typical weapons are two GBU-10 or GBU-27 guided bombs. It is possible to install AGM-88 HARM, AGM-65 “Maverick” missiles, B-61 or B-83 atomic bombs (two each), GBU-15 bomb or BLU-9 container. It is possible to install rail guides for AIM-9 “Sidewinder” on the beam.
Production
All production aircraft were produced in modification “A”. 64 units were produced, with the last production example delivered to the US Air Force in 1990.
Operation of the F-117
The existence of the F-117 aircraft was first officially recognized on November 10, 1988, when the Pentagon issued a press release describing the history of the aircraft and released one retouched photograph. The first public display of two F-117s took place on April 21, 1990. The aircraft was first presented at the Le Bourget air show only in 1991 after Operation Desert Storm.
Accidents and disasters
In the entire history of operation of F-117 aircraft, according to official data, 7 aircraft were lost, including one F-117 that was shot down during combat operations.
Combat use
- US Invasion of Panama (1989)
- Gulf War (1991)
- Operation Desert Fox (1998)
- NATO war against Yugoslavia (1999)
- Iraq War (2003)
Removal from service
The US Air Force planned to use the F-117 until 2018, but rising costs for the program and the obsolescence of the bomber in front of the new fighter forced it to abandon the F-117 in favor of the F-22.
Stealth technology can be compared to the effect of surprise, because in war, if you can achieve the effect of surprise, then you will have a huge advantage. So, an example would be Baghdad, which was subjected to night bombings by planes called “Black Ghosts”. These stealth aircraft were created by Lockheed. Everything would be fine, but Baghdad, at that time, had the most solid guarded airspace.
So what is Stealth technology?
Thanks to this technology, which was not invented by chance, enormous progress has been made. For example, the navy has been using this technology for more than 30 years to camouflage submarines. The Army also uses this technology to reduce infrared radiation from military equipment such as tanks.
The whole point of Stealth technology is to reduce the visibility of any technology in any of its manifestations. Both infrared and radar.
It is known that any equipment reflects radio waves that fall on it, and which are picked up by radar. This is radar signature. It, that is, radar, is characterized by a large scattering area (the ability of an object to scatter an electromagnetic wave).
As an example: the effective dispersion area of a bomber and a heavy bomber is 100 and 13-20, respectively; conventional fighter - 3-12. But the scattering area of an invisible aircraft is only 0.3-0.4 square meters. m. “Stealth” technology is based on two characteristics:
- maximum absorption of radio radiation by the aircraft body;
- the reflection of radio waves in a completely different direction than the one from which they were sent from the radar. For this characteristic, a special coating and a specific aircraft shape are used.
Aviation has long been developing something similar to stealth aircraft. So, back in 1962, Lockheed was seriously working on creating an aircraft, the little-known A-12 aircraft. Even then, the aircraft of that time, the SR-71 Blackbird, had already implemented Stealth technology in the form of a special coating and material design.
As you know, at the dawn of the 70s there was a serious upsurge in the field of programming and IT technologies, which, in turn, gave impetus to the development of aircraft manufacturing. Then a software called “ECHO” appeared, which helped the Lockheed company simulate various aircraft models, body designs and display them on the computer screen, obtaining their final appearance on the radar without building a real aircraft.
The result of these programming and studies was the production of a new aircraft, a prototype of the F-117A stealth aircraft - "Have Blue". At the same moment, the Northrop team presented its development, but after a lot of research and testing using radar, the Northrop option was dropped.
The experimental flight of the Have Blue stealth aircraft took place in the winter of 1977. After him, the US Air Force command ordered 24 fighter aircraft, the first of which was built only in 1983, and 2 years later it was put into service.
After everyone was convinced of the example of the F-117A fighter and its technical validity in the concept of a stealth aircraft, the US Air Force command commissioned Northrop to develop a new fighter that would use the Stealth system on a large scale. The designers worked hard on its design and development work in 1979, which paid off when the new aircraft was officially presented to the public in 1988. And the name of the plane was B-2 “Spirit”.
Stealth plane - features
Having examined the short history of the creation of stealth aircraft, we move on to the basic principles of the Stealth technology that were used in their creation.
- To ensure that radar radiation is absorbed, aircraft use a special ferromagnetic coating on the body. When electrical radiation hits the coating, the microparticles of the material included in its composition change their orientation with a very high frequency, and this is actually where the radiation energy is spent. In addition, in the aircraft itself, everything that is present in it and what it is made of uses absorbent composites such as carbon fiber.
- In the body shape, rounded parts are almost never used. Instead, the shape is made up of many planes that reflect the radar beams not in the opposite direction, but in completely different directions. This is why the sweep of aircraft wings can increase.
- It is known that ordinary turbojet engines have a design that can be easily detected by radar. To prevent this from happening, a special diffuser is installed in front of the compressor, which has a sharp top and thus reflects the heat inside the aircraft body and, accordingly, extinguishes it.
- Engines that have a flat shape create a jet torch that has a wide angle of divergence of hot gases, which in turn dissipates heat flow and reduces the level of visibility in the infrared range.
- Also, both engines found in stealth aircraft are equipped with noise-reducing casings and a forced cooling system in order to reduce infrared emissions. And it happens like this: part of the air that passes through the air intakes goes to the exhaust zone, where it mixes with hot reactive gases and cools them.
- Those parts that, it would seem, should be approximately vertical, such as the pilot's seat, have a corrugated shape in order to dissipate the radiated energy of the radar.
- The tail of the aircraft, which has a V-shape (or butterfly), serves as a replacement for the two horizontal and one vertical planes of a conventional tail, which also tends to reduce visibility.
