What is the maximum altitude for operations with one engine inoperative on the CRJ 900?

The maximum altitude for operations with one engine inoperative on the CRJ 900 is 25,000 feet. This limitation is crucial because it ensures that the aircraft can maintain safe and controllable flight in case of an engine failure. At higher altitudes, the performance capabilities of the aircraft are significantly reduced due to the decreased availability of thrust, coupled with changes in aerodynamic efficiency and fuel consumption.

Operating above this altitude with one engine inoperative could compromise the aircraft's ability to maintain altitude, control, and potentially lead to handling issues. The limitation is established based on extensive testing and operational safety data, which demonstrate that 25,000 feet represents a safe operational ceiling under these specific conditions. Ground and flight crews are trained to adhere to these limitations as part of their safety protocols to ensure the aircraft's performance is within certified capabilities.