COW Gun, 1½ lb, Mk III

The Coventry Ordnance Works, (COW) Quick Firing, 1½ Pounder, gun was an automatic cannon which was tested in various airframes form the First World War, to the 1930s. It was finally adopted as the armament for the Blackburn Perth flying boat which saw squadron service between 1934 and 1936.

The COW gun, as it was known, was considered for a wide variety of roles including ground attack, anti-shipping and as an air-to-air weapon. In the latter role it underwent service trials, fitted to DH 4 aircraft for use against German bomber and airship raids but the Lewis machinegun fitted to a Foster mount proved a more effective and much lighter option.