A whipstall is an aerobatic maneuver in which one dives to increase velocity and then initiates a climb rather abruptly, holding a nose up pitch attitude while the aircraft slows to stall speed. At this point the aircraft will typically come to a near stop in the air and the nose will rotate downward. This starts another, steeper dive. One can start with a very minor dive-stall sequence and by linking a number of them in series quickly achieve dramatic dives and equally dramatic vertical climbs. This is especially impressive to spectators when done with a hang glider or other gliding aircraft, since there is no power available to correct mistakes.

The aircraft is very vulnerable at the top of the climb, when it is roatating in pitch, as the normal aerodynamic controls have no or little effect at such low airspeed. If the climb is nearly vertical and the plane stalls before the pilot can give some nose down pitch input, the aircraft can tail slide, that is fall toward the ground, tail first. The controls are useless in this scenario, or worse an input may cause the aircraft to roll or yaw before or as it rotates in pitch, which can make it very difficult to regain control before the aircraft breaks up.

The pilot needs to set the controls for a dive, or get his or her weight well forward in a hang glider, and wait for the nose to drop so the plane dives and resumes flying. If the pilot tries to slam the nose down, especially once the nose has started to drop, the resulting rotational force may easily cause the rotation to continue past vertical (due to inertia, and a tumble ensues. This leads to structural failure of the aircraft most of the time.

Very skilled aerobatic pilots can time inputs so that a hang glider can rotate to nose level at the top of a near vertical whipstall and resume normal flight, which looks like a movie special effect. A moderate whipstall is also the standard way to get sufficient airspeed (in the recovery dive) to do more advanced maneuvers, such as loops and wingovers. These activities require more airspeed than can be gotten by simply diving from level flight.

Except for performing aerobatics, there is little use to being skilled at whipstalls, though some experience with them can help at those odd times when one falls from strong lift into strong sink (doing an unplanned dive) in very turbulent conditions.

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