As an open-bolt machine gun, the Lewis was not well suited to synchronization on WW1 aircraft - but it was an ideal gun for flexible mounting. To suit this use, a series of aircraft-specific Lewis variations were made. Today, we are looking at a 1918 model made by Savage for the US, chambered in .30-06. It has a single rear spade grip, and no cooling shroud. Instead, a small metal cylinder was added just to protect the gas piston. It has a muzzle brake designed to increase back pressure and raise the rate of fire to 800 or 850 rounds/minute, and was fitted with 97-round double-height pan magazines. The sights are Norman wind vane sights, designed to automatically compensate for the deflection of the gun pointing in different directions relative to the aircraft’s own movement and orientation. By the end of the war, Savage had produced 32,231 aircraft Lewis guns, with this type being the final pattern.