What occurs if no cool-off period is allowed for a turbine engine before shutdown?

When a turbine engine is shut down without a sufficient cool-off period, the rapid decrease in temperature can lead to thermal stress on the turbine blades. As these components are made of materials designed to withstand extreme heat, they can still be vulnerable to warping due to uneven cooling rates. Different parts of the turbine can contract at different rates when the temperature drops suddenly, potentially causing distortion or misalignment of the blades.

This warping can negatively impact the engine's performance, affecting how the blades interact with airflow during subsequent operations. Maintaining a cool-off period allows the engine to gradually return to ambient temperature, minimizing the risk of such thermal stresses and preserving the integrity of the turbine components.