At what airspeeds must flight spoilers not be extended during flight?

Flight spoilers are critical components of an aircraft's control surface used to reduce lift and increase drag, especially during descent and landing. However, their deployment during flight is restricted based on the aircraft's airspeed to ensure safety and maintain adequate control.

The correct answer indicates that flight spoilers should not be extended below reference speed plus 10 knots indicated airspeed (KIAS). This guideline is crucial because extending spoilers at speeds lower than this threshold could lead to unintended changes in aircraft behavior, including loss of control or reduced maneuverability. The reference speed is essentially the minimum safe speed for the aircraft’s configuration, and allowing for an additional 10 knots provides a buffer that ensures the aircraft remains stable and controllable.

Proper understanding of airspeed limits associated with spoiler deployment is vital for pilots. It allows them to maintain the necessary aerodynamic conditions for safe flight, especially during critical phases such as approach or descent when stability is paramount.

This knowledge is reinforced by standard operating procedures and training manuals, which emphasize the importance of adhering to specific airspeed limits to avoid compromising aircraft safety.