In 1910 he went to work for the British & Colonial Aeroplane Company (later the Bristol Aircraft Co.) as manager of the propeller shop.

These comprised rights under British Patents relating to machines for shaping airscrew blades applied for by Lang.

The US Navy contracted Lang to supply them with propellers and paid for the construction of a factory at Whitestone on Long Island.

[9][10] In addition to his work in developing propellers and associated equipment, Lang found time in 1923 to patent a wheel for vehicles.

[11] In 1936 Lang joined the Board of Hordern-Richmond, another British company that was closely involved in the development and production of airscrews and propellers.