Spin Recovery

Tailspin - Unrecoverable Spins
... is behind the aft limit approved for spinning, any spin may prove to be unrecoverable except by using some special spin-recovery device such as a spin-recovery ... This is sometimes called a flat spin, although whether a flat spin is indeed unrecoverable depends on aircraft type and loading ... The plane spins on its belly around the normal axis ...

Tailspin - Entry and Recovery
... Some aircraft cannot be recovered from a spin using only their own flight control surfaces and must not be allowed to enter a spin under any circumstances ... If an aircraft has not been certified for spin recovery, it should be assumed that spins are not recoverable and are unsafe in that aircraft ... Important safety equipment, such as stall/spin recovery parachutes, which generally are not installed on production aircraft, are used during testing and certification of aircraft ...