A stealth aircraft , also called undetectable by radar aircraft , aircraft unseen or aircraft stealth (from the English stealth aircraft ), is an aircraft that is designed to absorb and deflect radiation from radar through stealth technologies . It is also common to be called “invisible”, which is not very correct, since in part these planes are perfectly visible and the “invisibility” is only before radars, and on the other, there are other invisible planes that do seek to minimize possible detection by visual means.
In general, the role of a stealth aircraft is to execute its action without being detected by the enemy’s systems. The stealth aircraft had an important participation in the Gulf War of 1990 .
The first generation of these aircraft included the F-117 Nighthawk and tended to use fuselages with angled surfaces to deflect radar emissions as well as use radar wave absorbing materials ( RAM ). The second generation is represented by the B-2 Spirit . The design of these aircraft is greatly benefited by advances in computers capable of modeling the response of an aircraft to radar radiation as well as improving aerodynamics , always at the expense of huge design concessions that reduce its performance and potential.
The 27 of March of 1999 , the first F-117 was shot down 30 km from Belgrade by the Army Yugoslavia by combining a good tactic and appropriate means (a very old radar Russian of wave long and no less ancient missile antiaircraft SA -3 of the same nationality). It was the beginning of the end. The weapon that had been presented as invincible suddenly showed all its vulnerabilities.
At present, “strictly stealth” aircraft are considered obsolete, in the opinion of the United States Air Force itself (their main operator). The rapid advances in remote sensing and digital signal analysis have made both the major powers and the intermediate countries capable of detecting and attacking this type of apparatus at increasing distances. Therefore, the mentioned design concessions no longer seem to be adequate, and the concept has quickly become obsolete. At present, all armament manufacturing countries incorporate furtive technologies to their products to hinder their detection and attack (as in the Lockheed Martin F-22 Raptor), but “fully stealth” devices such as the F-117 or the B-2 are no longer planned .
Summary
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- 1 invisible aircraft
- 1 Infrared Invisibility
- 2 Thermal traces
- 2 List of stealth aircraft
- 1 Manned
- 1.1 Stealth Designs
- 1.2 Design with reduced RCS (equivalent radar section)
- 2 Unmanned (completely stealthy)
- 1 Manned
- 3 Source
Invisible aircraft
The invisible aircraft is the product of the combination of several anti-detection factors and the use of a weakness of the AA / IR (infrared anti-aircraft) missiles.
Infrared invisibility
These missiles in its nose have a narrow-angle IR (Infrared) sensor (like the light of a flashlight) in whose area or pickup cone it is that they can “see” the target. If an airplane is located perpendicular to the axis of the missile (on one side) the missile does not see it and continues long. That is why AA missiles must be fired towards the point where the radar located on the ground sees the target. In case the radar fails to see the plane, there is no way to shoot towards the point where the plane is. The same goes for the AA missiles of the FF type, that is to say missiles that carry not an infrared sensor but a mini-radar, and even with the combined IR-FF.
As for the anti-detection factors, to avoid infrared detection or thermal detection, the turbines are first coated externally with asbestos and other thermal insulators, forming a thick layer between the aircraft’s plastic fuselage and the metal surface of the turbine body. The external fuselage for being of plastic contributes to the isolation. The tail of the plane after the exit or nozzle of the turbine becomes a little longer to dissipate the thermal jet further. This tail is made of double layer with Asbestos in the middle of the two layers formed by the external fuselage and the inner layer or cover. To reinforce the heat loss, the turbine is manufactured as small as possible and to operate at the minimum possible revolutions (RPM), hence the low speed of the F117.
Additionally, from the front cold air inlet mouth, a take is made through 4 or 6 small diameter ducts that go to the extension of the aforementioned tail, to cool the end of the turbine jet tail with cold air.
Thermal traces
But despite all this, the plane always retains a “hot spot” when viewed from behind or behind. If an AA-FF is fired from behind as it works in response to a radar echo, the missile does not see the plane. But if an AA-IR is shot from behind if he sees it and hits the target, and this was what happened in Kosovo with the F-117 shot down
As for the radar anti-detection method, it is a combination of several factors, first a plastic fiber material similar to glass fiber is used with the addition of an asbestos derivative , which has a low radar reflection like any speedboat with fiberglass helmet. To this is added a painting that has a low reflection to the radar waves. And finally the dihedral surface design is added, to take advantage of a physical principle that says that the angle of reflection is equal to the angle of incidence, with respect to the plane where the rebound is made.
However, modern high-sensitivity microphones, extreme sensitivity audio amplifiers and high linear amplification factors, as well as pass-band audio filters (which discriminate the sonic frequency to a narrow soundtrack equivalent to the plane’s sound), allow detection with great accuracy over long distance. The microphones, with their parabolic reflector, are mounted on «batteries» of up to 100 groups as a kind of Yagi directional antenna . In addition, the sound of the plane in the air cannot be disguised and Chinese researchers have managed to design and build a low frequency radar that bounces off low reflection surfaces at high frequencies.
List of stealth aircraft
Manned
Stealth designs
Retired
- F-117 Nighthawk– Lockheed Martin
In service
- B-2 Spirit– Northrop Grumman
- F-22 Raptor– Lockheed Martin and Boeing
Developing
- F-35 Lightning II(JSF) – Lockheed Martin , BAE Systems and Northrop Grumman
- Sujoi T-50 PAK FA– Sujoi
- FGFA– Hindustan Aeronautics Limited
- Medium Combat Aircraft– Hindustan Aeronautics Limited
- Mitsubishi ATD-X– Mitsubishi Heavy Industries
- F-15SE Silent Eagle– Boeing
- Sujoi Su-47– Sujoi
- Chengdu J-20– Chengdu Aircraft Industry Group -Call also (J-XX) by the intelligence of the Naval USA
- HESA Shafaq– Iran Aircraft Manufacturing Industrial Company
Canceled
- Atlas Carver– Atlas Aircraft Corporation
- A-12 Avenger II– McDonnell-Douglas and General Dynamics
- Boeing X-32(JSF) – Boeing
- YF-23 Black Widow II– Northrop and McDonnell Douglas
- MBB Lampyridae– Messerschmitt-Bölkow-Blohm
Technology demonstrators
- BAE Replica– BAE Systems
- Boeing Bird of Prey– Boeing
- Lockheed Have Blue– Lockheed Corporation
- Northrop Tacit Blue– Northrop Corporation
- Northrop YB-49– Northrop Corporation
- Northrop YB-35– Northrop Corporation
- Horten Ho 229– Gothaer Waggonfabrik
- Horten Ho XVIII– Junkers and Messerschmitt
Design with reduced RCS ( equivalent radar section )
- SR-71 Blackbird– Skunkworks Blackbirds was the first regional support aircraft production started in 1962 with the CIA A-12 , and later with the SR-71 , YF-12 and M-21 , thus forming the Blackbird aircraft series .
- Avro Vulcan– British strategic bomber with hang glider and buried engines that gave rise to a low frequency radar.
- B-1 Lancer
- Dassault Rafale– French Air Force
- De Havilland Mosquito– British bomber with light and ground attack aircraft, mostly made of wood, low radars against the radar of principles.
- Eurofighter “Typhoon”
- F-15 EagleC and D – United States Air Force .
- F-15E Strike Eagle– United States Air Force .
- F-16 Fighting FalconC / D and E / F – United States Air Force .
- F / A-18 HornetC / D – Low frequency radar similar to the F-16 .
- F / A-18E / F Super Hornet– Low frequency radar with more advanced technology.
- Shenyang J-11B ‘Flanker’-Radar similar to the F-16 , based on that of the Su-27 .
- Messerschmitt Me 163 Kometrocket-propelled fighter aircraft.
- Mikoyan MiG-29Radar similar to F-16 C / D.
- Tupolev Tu-160– It was designed to reduce both radar and infrared detectability.
- PZL-230 Skorpion
Unmanned (completely stealthy)
- Boeing X-45– Boeing – ( technology demonstrator )
- BAE Taranis– BAE Systems ( technology demonstrator )
- Dassault nEUROn– ( technology demonstrator )
- EADS Barracuda– EADS , developed between Spain and Germany. ( technology demonstrator )
- Rheinmetall KZO– Rheinmetall ( UAV tactical )
- RQ-3 Dark Star– Lockheed ( canceled )
- S4 Ehécatl– Hydra Technologies of Mexico
- E1 Gavilán– Hydra Technologies of Mexico
- S5 Kukulkan– Hydra Technologies of Mexico ( in development )
- G1 Guerrero– Hydra Technologies of Mexico ( in development )
- IAI Heron– Israel Aerospace Industries
- IAI Searcher– Israel Aerospace Industries
