Scarff ring

The mount incorporated bungee cord suspension in elevation to compensate for the weight of the gun, and allowed an airgunner in an open cockpit to swivel and elevate his weapon (a Lewis machine gun) quickly, and easily fire in any direction.

In either case, the mounting was simple and rugged, and gave its operator an excellent field of fire.

Although it was a seemingly simple device, later attempts to emulate the Scarff ring as a mounting for the dorsal Vickers K in the World War II Handley Page Hampden bomber were failures.

Handley Page had designed a carriage with ball-bearing wheels running on a track around the cockpit.

In British use the Scarff ring was replaced in the 1930s by specialised power-operated turrets such as those made by Boulton Paul or Nash & Thompson, aircraft air speeds having by then risen to the point where a manually-operated gun was infeasible.