What is the maximum duration for the first engine start on the ground?

The maximum duration for the first engine start on the ground is 90 seconds. This limit is established for several reasons, including engine health, safety considerations, and operational efficiency.

During the initial start, the engine needs to reach proper operating parameters; if it fails to start within the allotted time, maintaining the start attempt for too long can lead to overheating or other mechanical issues. The 90-second limit ensures that if the engine does not start in that timeframe, the procedure is safely discontinued to avoid potential damage.

In training and standard operating procedures, adherence to these limits is crucial for maintaining the longevity of the aircraft's systems and ensuring safe practices during ground operations. Understanding these time constraints is essential for pilots during pre-flight preparations and emergency procedures.