What is the maximum continuous N2 percentage?

What is the maximum continuous N2 percentage?

• A. 97%
• B. 98%
• C. 99%
• D. 96%

Answer: (B)

N2 is the speed of the high‑pressure compressor spool, and engines set limits to protect the hot section and rotating components during different phases of flight. The maximum continuous N2 is the highest speed you can run the engine at for an extended period without overheating or overstressing the hardware. For the CRJ‑550, that continuous limit is 98%. Keeping N2 at or below 98% allows steady, long-duration operation without pushing into temperatures or stresses that could occur at higher speeds. Pushing to 99% would exceed the continuous safety margin, while 96% or 97% are simply lower than the maximum continuous limit and are not the highest allowable value.

N2 is the speed of the high‑pressure compressor spool, and engines set limits to protect the hot section and rotating components during different phases of flight. The maximum continuous N2 is the highest speed you can run the engine at for an extended period without overheating or overstressing the hardware. For the CRJ‑550, that continuous limit is 98%. Keeping N2 at or below 98% allows steady, long-duration operation without pushing into temperatures or stresses that could occur at higher speeds. Pushing to 99% would exceed the continuous safety margin, while 96% or 97% are simply lower than the maximum continuous limit and are not the highest allowable value.