Max N2 (Red) for the CRJ-550 is what percentage?

Max N2 (Red) for the CRJ-550 is what percentage?

• A. 99.0%
• B. 99.4%
• C. 99.8%
• D. 98.9%

Answer: (B)

The concept being tested is the engine spool speed limit, specifically the redline for N2. N2 is the core (high-pressure) spool speed, and the red line marks the maximum allowable value to protect the engine from overspeed and potential damage during throttle transients or gusts. For the CRJ-550, the redline N2 is set at 99.4% to maintain a safe margin below 100% while accounting for instrument tolerances and transient spikes. That’s why 99.4% is the correct limit. Values higher than that would risk surpass­ing the engine’s design limits, while lower numbers aren’t the official redline.

The concept being tested is the engine spool speed limit, specifically the redline for N2. N2 is the core (high-pressure) spool speed, and the red line marks the maximum allowable value to protect the engine from overspeed and potential damage during throttle transients or gusts. For the CRJ-550, the redline N2 is set at 99.4% to maintain a safe margin below 100% while accounting for instrument tolerances and transient spikes. That’s why 99.4% is the correct limit. Values higher than that would risk surpass­ing the engine’s design limits, while lower numbers aren’t the official redline.