Allison Prop-Jet info Prop-Jet (also referred to as Turbo Prop) Principles of Operation: Air enters the compressor inlet and is compressed to over 6 times normal atmospheric pressure. This high-pressure air is discharged rearward into the combustion chamber. The resulting hot combustion gases pass through two 2-stage turbines. The turbine receives power from these gases and drives the compressor, while the remaining energy is extracted by the power turbine which drives the power output shaft. This shaft delivers power to the propeller reduction gearbox, which is connected to the propeller. The Turbo Prop engine operates at essentially a constant speed. Variations in aircraft power are obtained by changing the pitch of propeller blades. The Allison Turbo Prop Model Kit was made in accurate detail from actual Allison blueprints. All major moving parts of the engine are represented in this 16 inch long replica.
