Shown here is a Gannet A.S. Mk.1. The Gannet was unique in being powered by the Double Mamba turboprop driving contra-rotating propellers. One half of the engine could be shut down to extend range and endurance. The original Fairey GR.17/Type Q prototype provided accommodation for a pilot and observer but production aircraft featured an additional cockpit for a third crew member. (Fleet Air Arm Museum)