Evidence
There is no strict set of guidelines an aircraft must meet or features it must have in order to be classified as supermaneuverable. However, as supermaneuverability itself is defined, the ability of an aircraft to perform high alpha maneuvers that are impossible for most aircraft is evidence of the aircraft's supermaneuverability. Such maneuvers include Pugachev's Cobra and the Herbst maneuver (also known as the "J-turn").
Some aircraft are capable of performing Pugachev's Cobra without the aid of features that normally provide post-stall maneuvering such as thrust vectoring. Advanced fourth generation fighters such as the Su-27, MiG-29, and F/A-18 along with their variants have been documented as capable of performing this maneuver using normal, non-thrust vectoring engines. The ability of these aircraft to perform this maneuver is based in inherent instability like that of the F-16; the MiG-29 and Su-27 families of jets are designed for desirable post-stall behavior. Thus, when performing a maneuver like Pugachev's Cobra the aircraft will stall as the nose pitches up and the airflow over the wing becomes separated, but naturally nose down even from a partially inverted position, allowing the pilot to recover complete control.
The Cobra, as performed by non-thrust vectoring aircraft, still depends on the aircraft moving through air; however, it does not involve the aircraft's aerodynamic surfaces and normal laminar airflow, but rather the whole airframe as a solid shape travelling through air, and its center of gravity in relation to the thrust vector. Being performed under conditions far beyond normal aerodynamic control and well into a stall without thrust vectoring, this is a form of passive supermaneuverability, possible because of aircraft design rather than thrust vectoring, which provides a way to actively control the aircraft well outside of the normal flight envelope.
The Herbst Maneuver, however, is believed to be impossible without thrust vectoring as the "J-turn" requires a half-roll in addition to pitching while the aircraft is stalled, which is impossible using conventional control surfaces. Pugachev's Cobra can be performed with less change in altitude if vectored thrust is used, as the aircraft can be made to pitch far more rapidly, both inducing the stall before the aircraft significantly gains altitude and recovering level attitude before altitude is lost.
Read more about this topic: Supermaneuverability
Famous quotes containing the word evidence:
“Never say a humorous thing to a man who does not possess humour. He will always use it in evidence against you.”
—Herbert, Sir Beerbohm (1853–1917)
“Nor is any evidence to be found, either in History or Human Nature, that nations are to be bribed out of a spirit of encroachment and aggression, by humiliations which nourish their pride, or by concessions that extend their resources and power.”
—James Madison (1751–1836)
“I believe that no characteristic is so distinctively human as the sense of indebtedness we feel, not necessarily for a favor received, but even for the slightest evidence of kindness; and there is nothing so boorish, savage, inhuman as to appear to be overwhelmed by a favor, let alone unworthy of it.”
—Marcus Tullius Cicero (106–43 B.C.)