A spin is an aggravated stall where one wing stalls more deeply than the other, causing the aircraft to autorotate (rotate continuously on its own) around a near-vertical axis while descending steeply. Every spin begins with a stall.
How It Works#
A stall occurs when a wing exceeds its critical angle of attack, the angle at which airflow separates from the wing and lift collapses. In a spin, one wing stalls before the other. That wing drops, and the asymmetry drives the aircraft into rotation.
The rotating wing that is more deeply stalled produces less lift and more drag than the opposite wing. This difference sustains the rotation without pilot input. The aircraft descends in a tight, nose-low spiral with a high angle of attack on both wings.
A spin has four phases: entry, incipient, developed, and recovery. The incipient phase is the first one to two turns, where the rotation is still building. The developed phase follows, with a stable, repeating rotation rate and descent path. Recovery requires specific control inputs to stop the rotation before pulling out of the resulting dive.
The standard recovery technique follows the PARE sequence: Power to idle, Ailerons neutral, Rudder full opposite to the direction of rotation, then Elevator forward to break the stall. Once rotation stops, the pilot pulls out of the dive smoothly.
Example in Aviation#
A student pilot is practicing slow flight at 3,500 feet AGL (above ground level). While distracted, the aircraft slows below stall speed in a coordinated left bank. The left wing drops suddenly and the nose pitches down sharply. The aircraft begins rotating to the left and descending nose-low. The student recognizes the developed spin and applies PARE: power off, ailerons neutral, full right rudder, then forward elevator pressure. Rotation stops after one additional turn, and the pilot recovers from the resulting dive.
Why It Matters#
Spins kill pilots. Most fatal spin accidents happen close to the ground during the traffic pattern, especially in the turn from base leg to final approach. At low altitude, there is no time to recover.
Understanding spin aerodynamics helps pilots recognize the conditions that lead to one: high angle of attack, yaw (sideways rotation), and low airspeed. Spin awareness training is required for flight instructor certificates under 14 CFR §61.183. Private pilots are required to demonstrate stall awareness and spin entry recognition, though not full spin recovery, per 14 CFR §61.107.
Key Takeaways#
- A spin requires a stall first. No stall, no spin.
- Asymmetric lift and drag between the two wings drives autorotation.
- The PARE sequence is the standard spin recovery technique.
- Most fatal spins occur in the traffic pattern at low altitude.
- Recognizing pre-spin conditions is more valuable than recovering from one.