Methods and systems are disclosed to operate an aircraft with modified (e.g., improved) flight performance characteristics, such as increased or maximized aircraft takeoff weight and/or longer allowable mission time for the aircraft. In one example, the aircraft may be enabled to operate with increased aircraft engine performance (e.g., such as engine power) without increasing engine temperature above the maximum allowable operating temperature limits for the engine. In a further example, available engine power may be determined during a pre-flight sequence, and utilized by an aircraft without exceeding published or manufacturer specified engine temperature limits.