What does NTS do?

• A. Increase blade angle when there is significant negative torque
• B. Decrease blade angle on takeoff
• C. Adjust engine timing
• D. Control fuel flow

Answer: (A)

NTS stands for Negative Torque Sensing. It’s a safety feature that monitors the drive-train for back-driven or reverse torque on the rotor. When it detects significant negative torque, it automatically increases the rotor blade pitch (blade angle) to raise rotor thrust. This helps prevent the rotor speed from decaying and keeps the rotor system stable when the engine isn’t supplying normal torque or the rotor is being loaded in a way that would slow it down. Engine timing and fuel flow are managed by other systems, and reducing blade angle during takeoff would reduce lift, which isn’t helpful in this scenario.