What happens to the airspeed during a spin?

During a spin, the airspeed stabilizes between 120-135 KIAS due to the specific aerodynamic characteristics of the aircraft in a fully developed spin. In this situation, the airplane reaches a balance where the forces of gravity, lift, and drag create a predictable state.

As the aircraft rotates in a spin, the angle of attack is typically high, contributing to a very low effective lift, while drag increases significantly due to the stalled condition. Eventually, the aircraft achieves a steady state in the spin, where the airspeed stops decreasing further and enters a stabilization phase around that 120-135 KIAS range. This is critical for pilots to understand because it indicates the conditions under which they can expect the aircraft to be in a controlled spin situation, impacting recovery techniques and airspeed management during flight training.

The other choices describe scenarios that do not accurately reflect the behavior of the aircraft airborne dynamics in a spin scenario. For example, airspeed does not remain constant throughout the spin, sharply increase beyond a specific airspeed, or fluctuate unpredictably. Instead, the stabilization of airspeed is crucial for understanding how to manage and recover from spins effectively.