FAA Powerplant Written Practice Test

What is the primary function of reverse pitch propellers?

1. To enhance climb performance

2. To produce a positive blade angle

3. To slow the aircraft down after touchdown

4. To improve takeoff distance

The correct answer is: To slow the aircraft down after touchdown

The primary function of reverse pitch propellers is to slow the aircraft down after touchdown. When a propeller is set to reverse pitch, the angle of the blades is adjusted so that they push air forward rather than backward. This reverse thrust creates a force that counters the forward motion of the aircraft, effectively helping to decelerate it during or after landing. This capability is particularly useful for reducing the required stopping distance on shorter runways or during adverse weather conditions. While enhancing climb performance and improving takeoff distance are important functions in the operation of propellers, reverse pitch specifically aims to provide a means of reducing speed after landing. Producing a positive blade angle is also relevant in standard flight operations but does not pertain to the primary function of reverse pitch operation. Thus, the correct understanding of reverse pitch propellers emphasizes their role in deceleration during landing rather than enhancing performance during takeoff or climb.