What sum of time is permissible for maximum takeoff and go-around ITT limits of 1006 Degrees C and 990 Degrees C?

The maximum permitted time for takeoff and go-around ITT (Inter Turbine Temperature) limits, which are 1006 degrees Celsius for takeoff and 990 degrees Celsius for go-around, is typically specified in aircraft operation manuals. This time limitation is crucial for ensuring engine performance and safety, as prolonged exposure to high temperatures can lead to engine damage.

For maximum takeoff ITT limits of 1006 degrees Celsius, the commonly accepted permissible duration is often limited to 5 minutes. This is designed to provide an adequate safety margin to prevent overheating and consequent engine wear or failure. The 10-minute, 15-minute, and 20-minute durations exceed the established operational limits and are not typically specified in industry guidelines, as they would place the engine at higher risk for thermal stress and potential damage. Therefore, the choice of 5 minutes directly aligns with safety protocols and manufacturer guidelines regarding engine temperature management.