The Armstrong Siddeley Double Mamba is a turboprop engine design developed in the late 1940s of around 3,000–4,000 hp (2,200–3,000 kW). It was used mostly on the Fairey Gannetanti-submarine aircraft developed for the Fleet Air Arm of the Royal Navy.
Engine starting was by cartridge, however, forced air restart was achieved in flight. One engine could be shut down in flight to conserve fuel. Shutting down one engine also stopped one of the propellers.
Variants
Fairey Gannet flying with one half of its Double Mamba engine shut down
The Double Mamba engine was also proposed for the Westland Westminster, a 30-seat helicopter that was later built as a prototype powered by a pair of Napier Eland E220 turboshaft engines.