Drone Pilot Practice Exam

Which situation increases the likelihood of stalling a UAS?

1. Climbing at a slow speed

2. Making slow turns

3. Descending rapidly

4. Flying straight and level

The correct answer is: Climbing at a slow speed

Climbing at a slow speed significantly increases the likelihood of stalling a UAS (Unmanned Aerial System). Stalling occurs when the aircraft's angle of attack exceeds a critical point, causing a dramatic loss of lift. When climbing slowly, the aircraft may not maintain adequate airspeed to generate the lift needed to counteract the weight of the drone, especially as the angle of attack rises during the ascent. This combination of low speed and increased angle can easily push the aircraft beyond its critical angle of attack, resulting in a stall. In contrast, making slow turns, descending rapidly, or flying straight and level typically provide more consistent airflow over the wings, which helps to maintain lift. Specifically, turns, while they can create additional load factors, do not inherently reduce speed to the extent that it risks stalling unless combined with other factors. Rapid descents can actually improve airspeed for some configurations, and flying straight and level optimizes lift because the aircraft is usually at a safe speed and angle of attack.