What is the NR Power-Off Transient percentage limit for a maximum duration of 10 seconds?

• A. 70%
• B. 80%
• C. 90%
• D. 95%

Answer: (B)

The NR Power-Off Transient percentage limit for a maximum duration of 10 seconds is set at 80%. This limit is established to protect the helicopter's system components from undergoing excessive stress during transient conditions. When the rotor RPM decreases significantly, such as during a power-off scenario, it is crucial to maintain a limit to ensure the structural integrity of the rotor system and overall safety of the aircraft.

Exceeding this limit could lead to detrimental effects, including rotor blade damage or compromise in control effectiveness. The 80% threshold provides a margin that allows for transient events while ensuring that safety and performance parameters remain within acceptable bounds. Understanding these limits is essential for pilots as they navigate various flight profiles and emergencies.