Z battery

For the Royal Horse Artillery unit of the same name see Z Battery Royal Artillery

The Z Battery was a short range anti-aircraft weapon system, which launched 3-inch (76 mm) diameter rockets from ground-based single and multiple launchers, for the air defence of the United Kingdom in World War II.

The solid-fuel 3 inch (76 mm) rocket used by the Z Batteries was known as the UP-3 and had been developed in the late 1930s by the Projectile Development Establishment at Fort Halstead in Kent under the direction of Alwyn Crow and was related to the Royal Navy's 7 inch (178 mm) Unrotated Projectile. The naval weapon had been enthusiastically backed by Winston Churchill when he was First Lord of the Admiralty at the outbreak of war. By June 1940, Churchill was Prime Minister and he requested "large supplies of [rocket] projectors" for the anti-aircraft defence of the mainland. The development of all British rockets was under the control of Professor F A Lindemann and he enthusiastically backed Churchill's suggestion. The naval weapon was intended to bring down low flying aircraft with a trailing wire to the end of which was attached an explosive mine; however, the land based system was intended to have a high explosive warhead, detonated by a specially designed photoelectric proximity fuse. The rocket itself was propelled by special solvent-free cordite, which was initially manufactured at Bishopton in Scotland; in December 1940, a new propellant factory was commissioned at Ranskill, which was in production by the start of 1942. The metal working firm G. A. Harvey and Co of Greenwich was given the contract to manufacture the rocket bodies and over 1,000 had been made by September 1940.

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