Musical instruments with continuously variable pitch can effect a portamento over a substantial range.
A variation of the control grid is to produce the helix with a variable pitch.
Two small propellers with variable pitch were used for thrust and yaw control.
Monopipe is a variable open pipe which can produce variable pitches.
Its propellor was a two-blade metal design with variable pitch.
Unlike most other drums, they have a variable definite pitch.
They may be fixed or variable pitch.
Each engine has a variable pitch prop which can operate in forward or reverse.
It drives a two blade propeller with variable pitch in flight.
A conical spring can be made to have a constant rate by creating the spring with a variable pitch.