APR ITT limit for 5 Minutes?

APR ITT limit for 5 Minutes?

• A. 990C (5 Minutes)
• B. 1006C (2 Minutes)
• C. 1010C (3 Minutes)
• D. 980C (4 Minutes)

Answer: (A)

ITT, or turbine inlet temperature, has strict limits because excessive heat can damage turbine blades and other components. The engine limits chart sets maximum ITT values tied to how long you can sustain that temperature. The longer the duration, the more restrictive the limit tends to be, so for a five-minute window the limit is 990°C. The other numbers you see correspond to different time windows: 2 minutes at 1006°C, 3 minutes at 1010°C, and 4 minutes at 980°C. This is why 990°C for five minutes is the correct match—it’s the ITT limit specifically defined for that five-minute duration. Exceeding these limits can lead to engine damage and safety risks.

ITT, or turbine inlet temperature, has strict limits because excessive heat can damage turbine blades and other components. The engine limits chart sets maximum ITT values tied to how long you can sustain that temperature. The longer the duration, the more restrictive the limit tends to be, so for a five-minute window the limit is 990°C. The other numbers you see correspond to different time windows: 2 minutes at 1006°C, 3 minutes at 1010°C, and 4 minutes at 980°C. This is why 990°C for five minutes is the correct match—it’s the ITT limit specifically defined for that five-minute duration. Exceeding these limits can lead to engine damage and safety risks.