Self Launching Motor Gliders
However, there are some gliders that are capable of launching themselves by means of a small engine. These are called Self Launching Motor Gliders (SLMGs).
Some of these types have engines which retract and fold away when the required height is reached. Others have propellers which fold flat against the fuselage when the engine is switched off.
Sustainers
Others still have an engine which, while not strong enough to launch the glider, can be utilised in the air to sustain flight when the pilot cannot find lift. These “get you home” gliders are called, not surprisingly, “Sustainers”.
Touring Motor Glider
Another type of glider is the Touring Motor Glider (TMG), which resembles ordinary aircraft. These motor gliders, as the name suggests, are used mainly for touring where the engine can be throttled back or switched off altogether if the lift is strong enough. The engines on these types are generally fixed but the propeller on some types may be ‘feathered’ to ensure the least amount of drag when the engine is switched off