What is the minimum N1 for the TH-73A?

• A. 40%
• B. 45%
• C. 51%
• D. 55%

Answer: (C)

The minimum N1 for the TH-73A is correctly indicated as 51%. This value is crucial as it defines the minimum rotational speed of the engine's gas generator section during operation. Maintaining N1 at or above this threshold ensures optimal engine performance and efficiency, contributing positively to overall aircraft safety and operational reliability. Operating below this minimum could compromise engine function, potentially leading to issues such as inadequate thrust or difficulties in power management.

Understanding the importance of N1 is critical in the context of flight operations since it relates directly to the engine's ability to provide sufficient power during various phases of flight, including takeoff and climbing. This is why adhering to the specified minimum of 51% is paramount for pilots flying the TH-73A.