Interrupter gear is a term that covers two related technologies. The first is Synchronization gear, which is often incorrectly referred to as "interrupter gear"; this is a triggering device attached to the
machine gun armament of a
tractor-type
fighter aircraft so that it would fire only at certain times. This allows the gun to fire through the arc of a spinning
propeller without the bullets striking the blades. Introduced during the
First World War, the gun synchronizer was a significant development in the history of
air combat and remained in operational use until the
Korean War when the widespread adoption of
Jet aircraft rendered them obsolete.
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