What is indicated by a hung start in a turbine engine?

A hung start in a turbine engine refers specifically to a situation where, after the start sequence has been initiated, the engine does not reach the desired idle RPM. This indicates that the engine is experiencing some difficulty in generating sufficient power to stabilize itself at idle, often due to a variety of factors such as fuel delivery issues, mechanical problems, or inadequate airflow.

During a normal start, the engine should ignite and accelerate to idle RPM efficiently. However, in a hung start, while the start sequence may progress to a point where fuel has been introduced and the ignition has occurred, the engine's thrust or power output remains insufficient to achieve the needed RPM, leading to an unstable condition.

Recognition of a hung start is crucial as it helps operators assess the situation correctly and take necessary corrective actions to either rectify the start attempt or safely shut down the engine if needed.