The Machmeter is, on subsonic aircraft, a warning indicator.

The convergent nozzle has generally been used in engines for subsonic aircraft.

It was designed for use against high-speed subsonic aircraft.

It is highly unlikely that in the long term we will continue to meet our long-distance travel requirements with subsonic aircraft alone.

Jet engine design shifts significantly between supersonic and subsonic aircraft.

The system of a fixed tail surface and moveable elevators is standard in subsonic aircraft.

The Stooge was essentially a small subsonic aircraft with straight wings and a conventional tail layout.

Historically, recovery from a mach tuck in subsonic aircraft has not always been possible.

This suggested the use of thinner airfoils with much longer chord than designers would have used on subsonic aircraft.

It has been designed to be launched from subsonic or supersonic aircraft by means of an ejector release unit.