Tiltjet
A tiltjet is an aircraft propulsion configuration that was historically tested for proposed vertical take-off and landing (VTOL)-capable fighters.
The tiltjet arrangement is, in concept, broadly similar to that of the tiltrotor; whereas a tiltrotor utilises pivotable rotors, the tiltjet employs jet engines capable of moving to angle their thrust between downwards and rearwards positions. A typical arrangement has the engines mounted on the wingtips, in which the entire propulsion system is rotated from axial to dorsal in order to achieve the transition from hover or vertical flight to horizontal. Aircraft of such a configuration are fully capable of performing VTOL operations, akin to a helicopter, as well as conducting high speed flights. However, the configuration has been restrained to experimental aircraft only, as other configurations for VTOL aircraft have been pursued instead.