Which statement best describes the labeling of the N1, N2, oil temperature, and oil pressure limits provided for the CRJ-550?

Which statement best describes the labeling of the N1, N2, oil temperature, and oil pressure limits provided for the CRJ-550?

• A. N1 and N2 are maximum values; oil temperature is a maximum; oil pressure is a minimum.
• B. All four values are maximum limits.
• C. All four values are minimum limits.
• D. N1 is minimum while N2, oil temperature, and oil pressure are maximum.

Answer: (A)

The limits are labeled to reflect how each parameter governs safe operation. N1 and N2 are engine spool speeds, expressed as percentages, and the maximum allowable values prevent the turbofan from overspeeding, which could damage the engine. Oil temperature is shown with a maximum limit because excessive temperature leads to thermal damage and reduced lubrication reliability. Oil pressure is listed with a minimum limit to ensure there’s always enough oil pressure to properly lubricate bearings; dropping below this minimum risks oil starvation and component damage. That combination—N1 and N2 as maximum values, oil temperature as a maximum, and oil pressure as a minimum—fits how these parameters are managed in jet engine limits. The other options would imply all are max, all are min, or flip N1 to a minimum, none of which align with how these limits are typically presented.

The limits are labeled to reflect how each parameter governs safe operation. N1 and N2 are engine spool speeds, expressed as percentages, and the maximum allowable values prevent the turbofan from overspeeding, which could damage the engine. Oil temperature is shown with a maximum limit because excessive temperature leads to thermal damage and reduced lubrication reliability. Oil pressure is listed with a minimum limit to ensure there’s always enough oil pressure to properly lubricate bearings; dropping below this minimum risks oil starvation and component damage. That combination—N1 and N2 as maximum values, oil temperature as a maximum, and oil pressure as a minimum—fits how these parameters are managed in jet engine limits. The other options would imply all are max, all are min, or flip N1 to a minimum, none of which align with how these limits are typically presented.