What is the status of using slats/flaps above 15,000 feet?

The use of slats and flaps above 15,000 feet is prohibited in the Endeavor Air CRJ 900. This limitation is in place primarily to ensure safety and performance during the aircraft's cruise phase. Above this altitude, the aerodynamic conditions and performance characteristics of the aircraft can change, necessitating a clean configuration to maintain optimal flight efficiency and control. Engaging slats and flaps at higher altitudes could adversely affect the aircraft's performance, such as stall characteristics and drag, which are critical factors for safe flight operations. Therefore, adhering to this limitation is essential for ensuring the safety of the flight.