FAA Commercial Pilot Airplane (CAX)Aerodynamics and PerformanceMedium
An airplane flying slower than its L/D max speed requires progressively MORE power to maintain altitude as airspeed decreases further. This flight condition is known as the:
- Aaccelerated stall regime
- Bmaneuvering speed boundary
- Cnormal command region
- Dregion of reverse command
Show answer & explanationAnswer & explanation
Correct answer: D. region of reverse command
The region of reverse command, also called flying "behind the power curve," occurs at airspeeds below L/D max where total drag increases as speed decreases, requiring more power (not less) to maintain altitude. This is the opposite of normal flight, where reducing speed reduces required power.
Why the other options are wrong
- A. Accelerated stalls relate to load factor, not the power-required curve.
- B. Maneuvering speed relates to structural load limits, not power-required behavior.
- C. In the normal command region, less power is needed as airspeed decreases toward L/D max.
Region of Reverse Command
The flight regime at airspeeds slower than L/D max where additional power is required to maintain altitude as airspeed decreases, due to rapidly increasing induced drag.
- Also called 'behind the power curve'
- Occurs below L/D max speed
- Common during slow approaches and landings
Memory trick: Behind the curve, slower needs more power, not less.