What control surfaces are locked when the gust lock is engaged?

The correct answer is that all control surfaces are locked when the gust lock is engaged. The gust lock is a safety mechanism utilized in aircraft to prevent the movement of control surfaces during periods of inactivity, particularly when the aircraft is parked.

When engaged, the gust lock secures the ailerons, rudder, and elevator in neutral or fixed positions. The primary purpose of this is to protect the flight control surfaces from being inadvertently deflected by wind gusts that could lead to misalignment or even damage while the aircraft is grounded. By locking all major control surfaces, it ensures that the aircraft remains stable and safeguarded against environmental conditions that could cause movement. This is particularly important for preserving the integrity of the aerodynamic surfaces and maintaining the aircraft's structure when it is unoccupied and not in flight.