What is the maximum ITT when in idle?

The correct option is 750 degrees Celsius, which is the maximum inter-turbine temperature (ITT) allowable when the engine is at idle. This temperature limit is crucial for preventing damage to the engine components and ensuring safe operational conditions.

When the engine is at idle, it is still producing thrust, albeit at a lower power setting, and the ITT can rise due to various factors such as ambient temperature, engine condition, and other operational parameters. Maintaining the ITT below this threshold is essential for engine longevity and reliability. Exceeding this temperature can lead to overheating, potential damage, or even engine failure.

The other choices reflect temperatures that could be found in various operational contexts, but they do not represent the idle condition’s safety limits. Understanding these limits is vital for effective aircraft operation and maintenance in training on the T-6A.