Technology / Aviation / Sailplane: An unpowered, soaring aircraft capable of maintaining level flight for long periods of time after release from tow and of gaining altitude using wind currents, as opposed to a GLIDER.
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Technology / Aviation / Glider: An unpowered aircraft capable of maintaining altitude only briefly after release from tow, then gliding to earth. Compare SAILPLANE. MORE
Technology / Aviation / Variometer: A panel instrument, often as simple as a tiny ball in a vertical tube, indicating subtle PITCH movements of an aircraft. Popular use in SAILPLANES. MORE