When should the rotor brake be operated in relation to engine status?

• A. During normal flight
• B. Only in emergency situations
• C. Until both engines are shut down and rotor RPM is below 50%
• D. When rotor RPM is above 70%

Answer: (C)

The operation of the rotor brake is crucial for ensuring safety and mechanical integrity during the shutdown process of a helicopter. It is important to engage the rotor brake only after the engines have been shut down and when the rotor RPM is sufficiently low to prevent damage. Operating the rotor brake until both engines are shut down and the rotor RPM drops below 50% ensures that the rotor system is safely immobilized without excessive rotational forces that could lead to mechanical failure or damage to the rotor components.

This practice prioritizes safety and the longevity of the helicopter’s mechanical system by preventing abrupt stops at higher RPMs, which can cause stress or wear on the braking system and rotor hub. Understanding this procedure is essential for proper operational protocol following flight, ensuring a thorough deactivation process in line with safety standards.