As a result of a government-sponsored report and pressure from British manufacturers, who saw Wackett as a threat to their monopoly on Australian orders, the Randwick Station was closed in 1931. Wackett resigned from the RAAF with the rank of wing commander and transferred (with some personnel and equipment) to the Cockatoo Island Naval Dockyard. Here he was involved in the design of watercraft as well as aircraft. He continued working for the RAAF – a single de Havilland D.H.60G Gipsy Moth was built at the Dockyard under his supervision and entered RAAF service in 1933. He also undertook civilian aviation projects including repair and modification projects, and built the Cockatoo Docks & Engineering LJW.6 Codock, a six passenger airliner powered by two Napier Javelin engines of , for Sir Charles Kingsford Smith. A later design for a larger aircraft, the 4-engined Corella, did not leave the drawing board, nor did his other aircraft concepts; VH-URP, the solitary Codock, was the only Wackett aircraft design built at the Dockyard. His marine designs at the Dockyard included small motorboats such as the "Cettien" (which won the Griffith Cup in 1934 and 1935) and the racing hydroplane "Century Tire II", and larger commercial passenger-carrying vessels as well.