performing a forced vertical climb with no thrust, usually ending with the aircraft performing a short climb or stalling instead of completing the cobra movement), among other examples. Some conventional aircraft can however perform maneuvers reminiscent of the cobra but do so with differences which disqualify them as real cobra maneuvers such as: performing at low speed, changing alpha too slowly and using advanced thrust control so as not to gain altitude (i.e. This is because conventional aircraft are designed to lack this "instability" for safety reasons, and can thus not execute the maneuver by conventional means. Only specific aircraft feature this "instability" and thus the maneuver can only be performed by a small number of aircraft. To be able to perform this rapid vertical pitchup the aircraft needs an "aerodynamic instability" in its core aerodynamics which will make the aircraft rapidly pitch up by itself once the elevator of the aircraft is pitched to the point where it breaks the airflow during a pitch up but also post-stall control and stability to not enter an uncontrollable stall at the peak of the pitch which then allows the aircraft to center the elevator and using the torque from the elevators added drag to pitch forward and make an aerodynamic recovery to horizontal flying again. Since the maneuver requires the aircraft to not lose or gain substantial altitude during the maneuver, the change of alpha during the vertical pitchup has to be fast enough to break the airflow of the wings, as to not make the aircraft climb. The cobra maneuver requires more than just pilot input and aircraft maneuverability to be performed. To execute the maneuver the aircraft only needs to use its standard aerodynamic controls, however executing it can be achieved more easily with the addition of modern thrust vectoring. High thrust is also needed throughout the maneuver to not stall out. Proper entry speed is necessary because, if the maneuver is entered too slowly, the plane might be unable to complete the maneuver or return to level flight with sufficient speed, while entering at too high a speed would create g-forces so high that the pilot loses consciousness or the airframe is damaged. To perform the cobra, the maneuver must be entered from fairly high subsonic speeds. This greatly lowers the speed of the aircraft due to the un-aerodynamic under-surface of the aircraft going against the airflow. The plane does not roll or yaw in either direction. If properly performed, the plane maintains nearly straight flight throughout the maneuver. The maneuver can simply be described as a rapid vertical pitchup from level flight without initiating a climb, followed by a forward-pitch back to level flight. Ĭobra maneuver schematic of the MiG-29 in profile, showing alpha numbers. The maneuver has never been verified in real combat, although it has been used during mock dogfights and border protection. The maneuver is typically performed at air shows, but could be used as a last-ditch maneuver to force a chaser to overshoot in close-range air combat. The Herbst maneuver and the helicopter maneuver are similar post-stall maneuvers that are often executed by 4.5th Generation and 5th Generation fighter aircraft employing thrust vectoring. The cobra maneuver is an example of supermaneuverability, specifically poststall maneuvering. The maneuver demands accurate pitch control, alpha stability and engine-versus-inlet compatibility for the aircraft, as well as a high skill level on the part of the pilot. The maneuver relies on the ability of the plane to be able to quickly change angle of attack (alpha) without overloading the airframe, and sufficient engine thrust to maintain nearly constant altitude through the entire move, but also post-stall stability and aerodynamics that allows for the recovery to level flight. In aerobatics, the cobra maneuver (often shortened to the cobra), also called dynamic deceleration, among other names, is a dramatic and demanding maneuver in which an airplane flying at a moderate speed abruptly raises its nose momentarily to a vertical and slightly past vertical attitude, causing an extremely high angle of attack and momentarily stalling the plane, making a full-body air brake before dropping back to normal position, during which the aircraft does not change effective altitude. The cobra maneuver performed by a Swedish Saab 35 Draken
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