No. 22 Squadron of the Royal Air Force was originally formed in 1915 as a reconnaissance unit equipped with BE2c aircraft, the squadron operated in France and Germany during and after WWI. The squadron went to France with FE2 aircraft but, from 1917, the squadron was equipped with the Bristol F2b also known as the Bristol Fighter or 'Brisfit'. As part of the post-war reduction of the military, the squadron was disbanded in 1919. By the time it was demobilized, it had had 27 flying aces within its ranks, both pilots and observers. The Lewis Gun was a light machine gun of American design that was perfected and widely used by the British Empire. It was extensively used on British and French aircraft during WWI. The Lewis's popularity as an aircraft machine gun was partly due to its low weight, the fact that it was air-cooled and that it used self-contained 97-round drum magazines. The Vickers gun became a standard weapon on British and French military aircraft, especially after 1916. Although heavier than the Lewis, its closed bolt firing cycle made it much easier to synchronize to allow it to fire through aircraft propellers. Captioned: "Lewis guns and Lewis and Vickers ammunition are issued to observers and pilots of No. 22 Squadron at the airfield Vert Gatland, April 1918."