Pugachev's Cobra
Encyclopedia
In aerobatics
Aerobatics
Aerobatics is the practice of flying maneuvers involving aircraft attitudes that are not used in normal flight. Aerobatics are performed in airplanes and gliders for training, recreation, entertainment and sport...

, Pugachev's Cobra (or Pugachev Cobra) is a dramatic and demanding manoeuvre in which a plane flying at a moderate speed suddenly raises the nose momentarily to the vertical position and slightly beyond, before dropping it back to normal flight. It uses a potent engine thrust to maintain approximately constant altitude through the entire move. The figure has several combat uses including spoofing doppler radar, and is also an impressive trick to demonstrate aircraft's pitch control authority, high angle of attack
Angle of attack
Angle of attack is a term used in fluid dynamics to describe the angle between a reference line on a lifting body and the vector representing the relative motion between the lifting body and the fluid through which it is moving...

 (AOA) stability and engine-versus-inlet compatibility, as well as the pilot's skill. The manoeuvre is named after the Soviet test pilot Viktor Pugachev
Viktor Pugachyov
Viktor Georgiyevich Pugachyov is a Russian test pilot who was the first to show the so called Pugachev's Cobra maneuver of Su-27 to the general public. He was named Hero of the Soviet Union in the late 1980s. He graduated from Yeysk military aviation school in 1970. Test-pilot school and MAI...

, who first performed the manoeuvre publicly in 1989 at the Paris
Paris
Paris is the capital and largest city in France, situated on the river Seine, in northern France, at the heart of the Île-de-France region...

 Le Bourget
Le Bourget
Le Bourget is a commune in the northeastern suburbs of Paris, France. It is located from the center of Paris.A very small part of Le Bourget airport lies on the territory of the commune of Le Bourget, which nonetheless gave its name to the airport. Most of the airport lies on the territory of the...

 air show
Air show
An air show is an event at which aviators display their flying skills and the capabilities of their aircraft to spectators in aerobatics. Air shows without aerobatic displays, having only aircraft displayed parked on the ground, are called "static air shows"....

.
Initially the Cobra was performed by Sukhoi
Sukhoi
Sukhoi Company is a major Russian aircraft manufacturer, headquartered in Begovoy District, Northern Administrative Okrug, Moscow, famous for its fighters...

's test pilot Igor Volk
Igor Volk
Igor Petrovich Volk was a cosmonaut and test pilot in the Soviet Union. He is married and has two children.Igor Volk was selected as a cosmonaut on July 30, 1980, flew as Research Cosmonaut on Soyuz T-12, the 7th expedition to Salyut 7...

 while testing the new Sukhoi Su-27
Sukhoi Su-27
The Sukhoi Su-27 is a twin-engine supermanoeuverable fighter aircraft designed by Sukhoi. It was intended as a direct competitor for the large United States fourth generation fighters, with range, heavy armament, sophisticated avionics and high manoeuvrability...

 fighter.

Description

In case of the Su-27, initially the pilot disengages the angle of attack limiter of the plane, normally set at 26°. This action also disengages the g limiter. After that the pilot pulls back on the stick hard. The aircraft reaches 90–120° angle of attack with a slight gain of altitude and a significant loss of speed. When the elevator is centered, the drag
Drag (physics)
In fluid dynamics, drag refers to forces which act on a solid object in the direction of the relative fluid flow velocity...

 at the rear of the plane causes torque
Torque
Torque, moment or moment of force , is the tendency of a force to rotate an object about an axis, fulcrum, or pivot. Just as a force is a push or a pull, a torque can be thought of as a twist....

, thus making the aircraft pitch forward. At that time the pilot adds power to compensate for the lift loss. In a properly performed Pugachev's Cobra, the plane maintains almost straight flight throughout the manoeuvre; the plane does not roll or yaw in either direction. Proper entry speed is significant because, if entering at too low a speed, the pilot might not be able to accomplish the manoeuvre; entering at too high a speed might result in the g-force
G-force
The g-force associated with an object is its acceleration relative to free-fall. This acceleration experienced by an object is due to the vector sum of non-gravitational forces acting on an object free to move. The accelerations that are not produced by gravity are termed proper accelerations, and...

 sufficient for the airframe to be damaged, or for the pilot to lose consciousness.

While Pugachev's Cobra can be executed using only standard aerodynamic controls, it could be achieved more easily with modern thrust vectoring
Thrust vectoring
Thrust vectoring, also thrust vector control or TVC, is the ability of an aircraft, rocket or other vehicle to manipulate the direction of the thrust from its engine or motor in order to control the attitude or angular velocity of the vehicle....

. In the latter case it would be an example of supermanoevreability, specifically poststall manoeuvreing. The Herbst manoeuvre
Herbst maneuver
The Herbst maneuver is an air combat maneuver which uses post-stall technology such as thrust vectoring and advanced flight controls to achieve high angles of attack. The Herbst maneuver allows an aircraft to quickly reverse direction using a combination of high angle-of-attack and rolling...

 and the helicopter manoeuvre are other examples of the recent growing use of vectored thrust in 4.5 and 5th generation aircraft, manned as well as unmanned.

Examples of aircraft capable of the manoeuvre

  • Sukhoi Su-27
    Sukhoi Su-27
    The Sukhoi Su-27 is a twin-engine supermanoeuverable fighter aircraft designed by Sukhoi. It was intended as a direct competitor for the large United States fourth generation fighters, with range, heavy armament, sophisticated avionics and high manoeuvrability...

     and variants (Su-30
    Sukhoi Su-30
    The Sukhoi Su-30 is a twin-engine, two-seat military aircraft developed by Russia's Sukhoi Aviation Corporation. It is a multirole fighter for all-weather, air-to-air and air-to-surface deep interdiction missions.The Su-30 started out as an internal development project in the Sukhoi Su-27 family...

    /Su-30MKI/Su-30MKM
    Sukhoi Su-30MKM
    -See also:...

     to Su-37
    Sukhoi Su-37
    The Sukhoi Su-37 is an experimental single-seat, supermaneuverable multirole jet fighter, designed by Sukhoi. A further development of the original Su-27 'Flanker', it was modified from the first-generation Su-35 prototypes...

    )
  • Mikoyan MiG-29
    Mikoyan MiG-29
    The Mikoyan MiG-29 is a fourth-generation jet fighter aircraft designed in the Soviet Union for an air superiority role. Developed in the 1970s by the Mikoyan design bureau, it entered service with the Soviet Air Force in 1983, and remains in use by the Russian Air Force as well as in many other...

      and Mikoyan MiG-35
    Mikoyan MiG-35
    The Mikoyan MiG-35 is a further development of the MiG-29M/M2 and MiG-29K/KUB technology. It is classified as a 4++ generation jet fighter by Mikoyan. The first prototype was a modification of the aircraft that previously served as MiG-29M2 model demonstrator. 10 prototypes have been built so far...

  • F-22 Raptor
    F-22 Raptor
    The Lockheed Martin/Boeing F-22 Raptor is a single-seat, twin-engine fifth-generation supermaneuverable fighter aircraft that uses stealth technology. It was designed primarily as an air superiority fighter, but has additional capabilities that include ground attack, electronic warfare, and signals...

  • Dassault Rafale
    Dassault Rafale
    The Dassault Rafale is a French twin-engine delta-wing multi-role jet fighter aircraft designed and built by Dassault Aviation. Introduced in 2000, the Rafale is being produced both for land-based use with the French Air Force and for carrier-based operations with the French Navy...

  • F-16 MATV/VISTA
    F-16 VISTA
    |-See also:-External links:* * * * *...

  • F/A-18 HARV
    High Alpha Research Vehicle
    The High Alpha Research Vehicle was a modified F/A-18 Hornet used by NASA in a 3-phase program investigating controlled flight at high angles of attack using thrust vectoring, modifications to the flight controls, and with actuated forebody strakes...

  • Rockwell-MBB X-31
    Rockwell-MBB X-31
    |-See also:-References:*Jenkins, Dennis R., Tony Landis, and Jay Miller. . NASA, June 2003.*USAF & NATO Report RTO-TR-015 AC/323//TP-1 .-External links:* * * *...

     (experimental)
  • Saab 35 Draken
  • J-10

See also

  • Cobra Turn
    Cobra Turn
    The Cobra Turn is a fighter aircraft maneuver. It is a variation on the Pugachev's Cobra where the aircraft performs the pull-up, but instead of returning to level flight applies rudder or thrust vectoring and turns downward...

  • Kulbit
    Kulbit
    The "Kulbit" is an aerial maneuver developed by Russian pilots, in which the aircraft performs an extremely tight loop, often not much wider than the length of the aircraft itself. It is an example of post-stall maneuvering, a type of supermaneuverability...

    , a more demanding combat manoeuvre (performed for example by Sukhoi Su-37
    Sukhoi Su-37
    The Sukhoi Su-37 is an experimental single-seat, supermaneuverable multirole jet fighter, designed by Sukhoi. A further development of the original Su-27 'Flanker', it was modified from the first-generation Su-35 prototypes...

    , etc.)

External links

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