This paper presents a method of predicting propeller speed and pitch stops of a twin turbine engine airplane, driven by a single propeller under FAR 23-commuter category regulation. The analysis includes integration of propeller and engine performance models with an example airframe. The propeller blade angle varied for its operational range at 75% disk radius in order to observe changes in powerplant performance within the airplane flight envelope. Performance data were generated to show the limitations in propeller pitch angle and rotational speed, engine power and flight speed. The prediction method should serve as guidance for those who work in preliminary design of a turboprop airplane.