Angle of Attack - Very High Alpha

Very High Alpha

Some military aircraft are able to achieve very high angles of attack, but at the cost of massive induced drag. This provides the aircraft with great agility. A famous military example is sometimes thought to be Pugachev's Cobra. This high pitch (the angle between the chord and level flight) maneuver is technically, by definition, not quite a true angle of attack, but is more accurately, supermaneuvering by means of thrust vectoring the whole airframe -- as the airflow, motion vector and wing chord or primary lift devices, are NOT in a classical angle-of-attack relationship).

Additional aerodynamic surfaces known as "high-lift devices" including leading edge wing root extensions allow fighter aircraft much greater flyable 'true' alpha, up to over 45°, compared to about 20° for aircraft without these devices. However, military aircraft usually do not obtain such high alpha in combat, as it robs the aircraft of speed very quickly. Not only do such maneuvers slow the aircraft down, but they cause significant structural stress at high speed. Modern flight control systems tend to limit a fighter's angle of attack to well below its maximum aerodynamic limit.