Introduction to Glider Flying > Components and Systems > Powerplant

Self-launch gliders are equipped with engines powerful enough to enable them to launch without external assis-tance. The engines also may be used to sustain flight if the soaring conditions deteriorate. Self-launch gliders differ widely in terms of engine location and type of propeller.

Figure 2-7. Self-launch gliders are different in performance, as well as appearance.

Some are equipped with a fixed, nose-mounted engine and a full feathering propeller. On other types of self-launch gliders, the engine and propeller are located aft of the cockpit. When the engine and propeller are not in use, they are retracted into the fuselage, reducing drag and increasing soaring performance. These types of self-launch engines are usually coupled to a folding propeller, so the entire powerplant can be retracted and the bay doors closed and sealed. [Figure 2-7]

Some gliders are equipped with sustainer engines to assist in remaining aloft long enough to return to an airport. However, sustainer engines do not provide sufficient power to launch the glider from the ground without external assistance. A more detailed explanation of engine operations can be found in chapter 7— Launch and Recovery Procedures and Flight Maneuvers.