Speedbrake deployment above which G is prohibited?

• A. +2.0
• B. +1.0
• C. +1.5
• D. +1.8

Answer: (C)

Speedbrake deployment is limited by the aircraft’s load factor to protect structural integrity and handling characteristics. When the airplane is experiencing positive G of +1.5 or more, extending the speedbrake can introduce a large drag change and an adverse aerodynamic/structural load that the airframe isn’t designed to handle safely in that regime. To avoid overstressing components or compromising control, deployment is prohibited above +1.5 G. In normal flight with lower G, the speedbrake can be used as intended for deceleration, but once you exceed this threshold, it must not be deployed.