Which range is designated as N1 takeoff/max?

Which range is designated as N1 takeoff/max?

• A. 60-100.1%
• B. 51%
• C. 95-101%
• D. 100.1-103.2%; 103.2% max (5 min)

Answer: (D)

N1 takeoff/max is the higher-than-idle thrust setting you may use briefly to achieve a safe takeoff, and it is strictly time-limited to protect the engine. N1 here refers to the speed of the fan/low-pressure spool, shown as a percentage of its maximum calibrated RPM. For takeoff, you’re allowed to push N1 above 100% to generate extra thrust, but you must stay within a defined upper range and not exceed the time limit. The designated range is 100.1% to 103.2%, with a maximum of 103.2% allowed for up to 5 minutes. This lets you achieve the necessary takeoff thrust while constraining temperature and mechanical stress, since sustained high N1 can overheat or wear components if kept too long. The other ranges don’t fit because they either don’t reach the takeoff thrust level, stay too low, or don’t reflect the explicit time-limited upper bound. So the correct designation is the range that explicitly captures the takeoff/max limit and the 5-minute cap.

N1 takeoff/max is the higher-than-idle thrust setting you may use briefly to achieve a safe takeoff, and it is strictly time-limited to protect the engine. N1 here refers to the speed of the fan/low-pressure spool, shown as a percentage of its maximum calibrated RPM. For takeoff, you’re allowed to push N1 above 100% to generate extra thrust, but you must stay within a defined upper range and not exceed the time limit.

The designated range is 100.1% to 103.2%, with a maximum of 103.2% allowed for up to 5 minutes. This lets you achieve the necessary takeoff thrust while constraining temperature and mechanical stress, since sustained high N1 can overheat or wear components if kept too long.

The other ranges don’t fit because they either don’t reach the takeoff thrust level, stay too low, or don’t reflect the explicit time-limited upper bound. So the correct designation is the range that explicitly captures the takeoff/max limit and the 5-minute cap.