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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.

An overview was constructed from available experimental data for static and dynamic stall characteristics of airfoils operating at low speeds. Emphasis was given to the history of changes in the boundary layer development. Separation and stall types were revisited to understand the physics involved with stall hysteresis. Fixed and variable speed, and dynamic stall hysteresis were studied. The study reveals the need to extend the parametric studies of single airfoils to multi-element airfoils. This is evident from wind tunnel tests of a flapped airfoil. Flap deployment brings the low Reynolds number hysteresis phenomenon back to the airfoil operating at relatively high test Reynolds number.