The Cypher is a type of unmanned aerial vehicle developed by Sikorsky Aircraft Corporation. It is a vertical takeoff and landing aircraft which uses two opposing rotors enclosed in a circular shroud for propulsion.

The single prototype first flew in April 1992 and flew untethered the following year. Since then, over 550 flights have been made in a series of demonstrations for the US government.

The doughnut-shaped Cypher can carry a sensor package on struts above its hull, or can be used to transport loads of up to 50 lb (23 kg).