SPINS

Description

An aggravated stall that results in what is termed “autorotation” wherein the airplane follows a downward corkscrew path.

Objective

To teach stall and spin aerodynamics, recognition, and recovery.

Setup

·         Pre-flight: weight and balance of the aircraft must be calculated before the maneuver to confirm that the airplane is within the utility category

·         Clear the area

·         Choose forced landing area (should be runway)

·         Configure aircraft for landing (except gear up): (C172R: 1500 RPM), altitude sufficient for recovery not below 1500’ AGL (ideally 5000’ AGL to start), flaps full, carburetor heat on

·         Select outside references for orientation

·         Power-off stall: reduce power to idle, simultaneously raise the nose

·         Add full rudder in direction of desired spin as airplane stalls

·         Apply full back pressure on elevator to the limit of travel

·         Ailerons in the neutral position

·         Take flaps out immediately

·         Allow spin to develop into a steady-state (developed) spin

Recovery

·         Power – reduce to idle

·         Ailerons – position to neutral

·         Rudder – full opposite against the rotation

·         Elevator – brisk elevator control full forward to brake stall

·         After spin rotation stops, neutralize the rudder

·         Smoothly apply back-elevator pressure to raise the nose to level flight

 

“PARE” is the recovery technique. Spins are an aerobatic maneuver. 14 CFR 91.303 governs where aerobatic maneuvers may be done: Uncongested area, not in class B, C, D, or E airspace near an airport or airway. 3+ statute mile visibility is required. A parachute is ordinarily required, but not for spins that are done when required for a rating (14 CFR 91.307(d)). The airplane must be in the utility category or aerobatic category to withstand the loads imposed during a spin. (Load factors for aircraft categories: Utility +4.4, -1.76; Normal +3.8, -1.52; Aerobatic        +6.0, -3.0.)

Common Errors

·         Failure to establish proper configuration prior to spin entry

·         Failure to achieve and maintain a full stall during spin entry

·         Failure to close throttle when a spin entry is achieved

·         Failure to recognize the indications of an imminent, unintentional spin

·         Improper use of flight controls during spin entry, rotation, or recovery

·         Disorientation during a spin

·         Failure to distinguish between a high-speed spiral and a spin

·         Excessive speed or accelerated stall during recovery

·         Failure to recover with minimum loss of altitude

·         Attempting to spin an airplane not approved for spins

References

FAA-H-8083-3A Airplane Flying Handbook p. 4-12

FAA-S-8081-6CS Flight Instructor for Airplane Single-Engine Land and Sea PTS p. 1-56