Career

In his early career he was a motor cycle racer for motorcycle manufacturers such as Brough Superior

Brough Superior

Brough Superior motorcycles, sidecars, and motor cars were made by George Brough in his Brough Superior works on Haydn Road in Nottingham, England, from 1919 to 1940. They were dubbed the "Rolls-Royce of Motorcycles" by H. D. Teague of The Motor Cycle newspaper. Approximately 3,048 of 19 models...

, McEvoy

McEvoy Motorcycles

McEvoy Motorcycles was a British motorcycle manufacturer based in Derby. The company used engines from Villiers, Blackburne, British Anzani and JAP...

 and the Belgian arms company FN. At Pendine, Wales he won the Welsh TT in 1925 and the Welsh TT sidecar in 1927 on Brough machines.

In 1930 he was recruited by the Czech arms manufacturer Frantisek Janecek

František Janeček

František Janeček was the founder of Jawa motorcycles and an important figure in the development of the Czech motorcycle industry. He died on 4 June 1941.-Early life:...

, founder of the JAWA motorcycle company. Janecek wanted to build a cheaper motor cycle than their current model. Patchett's contacts with the Villiers company enabled a new JAWA model to be designed around the Villiers 175cc two-stroke engine which proved very popular.

On the outbreak of WWII Patchett returned to England and started work under the auto-engineer George Lanchester

George Lanchester

George Herbert Lanchester, was an English engineer. He was one of three brothers who played a leading role in the early development of the UK auto-industry....

 at the Sterling Armaments Company

Sterling Armaments Company

Sterling Armaments Company was an arms manufacturer based in Dagenham, famous for manufacturing the L2A3 , AR18 and SAR-87 assault rifles and parts of Jaguar cars. The company went bankrupt in 1988....

 in Dagenham, Essex, helping to gear up manufacture of the Lanchester sub-machine gun. On his way out of Prague he managed to throw prototype samples of Janeček's new anti-tank device over the wall of the British Embassy.

By 1942 he was leading a design team to design a new sub-machine gun to the army's specification which was referred to as the "Patchett Machine Carbine". After successfully taking part in extensive army trials in the late 1940s it was adopted by the British Army to replace the Sten gun and known by them as the 9mm Sterling sub-machine gun L2A1. A modified version, the L2A3, was the very popular Sterling Mk IV which saw service until the 1990s.