- Johnson bar (vehicle)
: "This article is about a hand lever used in various vehicles, for other uses of the term, see
Johnson bar (disambiguation) ."A Johnson bar is a hand lever with several distinct positions and a positive clutch to hold the lever in the selected position. The positive
clutch is typically activated with a spring-loaded squeeze handle on the lever so that only one hand is needed to release the clutch, move the lever, then reengage the clutch.Many
steam locomotive s have valvetrain controls which are set using a Johnson bar as referenced in Fred Eaglesmith's Back There: "Hey Porter, tell that engineer, tell him this train's too slow. Tell him to let go that Johnson bar. I got places I got to go."Many trucks and buses use a hand brake which is controlled with a Johnson bar. These are sometimes called "Johnson bar brakes".
Truck drivers used to call lever controls on air-operated trailer brakes "Johnson bars".
On Caterpillar Tractors the forward / reverse lever is also called a Johnson bar.
Some light
general aviation aircraft (the Beech Musketeer and early models of the Cessna 172 among them) use Johnson bars to actuate flaps and wheel brakes; a small number of older aircraft also have landing gear actuated by Johnson bars.ee also
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