What is the NR power-on minimum percentage requirement?

• A. 100%
• B. 95%
• C. 105%
• D. 101%

Answer: (B)

The NR power-on minimum percentage requirement is established to ensure the proper operation and performance of the rotor system during flight. In the context of the TH-73A, maintaining the rotor speed at or above 95% during power-on is critical for achieving optimal flight characteristics and ensuring safety. This percentage is significant because operating below this threshold can lead to inadequate rotor blade performance, affecting lift generation and overall aircraft control.

When the rotor speed dips below this minimum requirement, it can result in compromised flight stability, which is particularly important during critical phases of flight such as takeoff and transitions. Proper rotor speed contributes to effective aerodynamic efficiency and helps mitigate the risk of rotor stall or loss of control. Thus, ensuring that NR maintains at or above 95% during power-on operations is essential for the safe and effective operation of the TH-73A.