Armstrong Siddeley Double Mamba

The Armstrong Siddeley Double Mamba is a turboprop engine design developed in the late 1940s of around . It was used mostly on the Fairey Gannet anti-submarine aircraft developed for the Fleet Air Arm of the Royal Navy.

Design and development

The Double Mamba (rarely known as the Twin Mamba) was a development of the Armstrong Siddeley Mamba with two Mambas driving contra-rotating propellers through a combining gearbox.

Engine starting was by cartridge; forced air restart was possible in flight. One engine could be shut down in flight to conserve fuel. Shutting down one engine also stopped one of the propellers.

Variants

ASMD.1: (2 x ASMa.3) used on Fairey Gannet A.S. Mk.1 and Blackburn B-88

ASMD.3: (2 x ASMa.5) used on Fairey Gannet A.S. Mk.4

ASMD.4: (2 x ASMa.6) used on Fairey Gannet AEW Mk.3

ASMD.8: (2 x ASMa.6) used on Fairey Gannet AEW Mk.3

Applications

• Blackburn B-88
• Fairey Gannet
• Fairey Gannet AEW

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.

Engines on display

Preserved Double Mamba engines are on public display at the:

• Australian National Aviation Museum
• Deutsches Museum Flugwerft Schleissheim
• Gatwick Aviation Museum
• South Yorkshire Aircraft Museum
• Imperial War Museum Duxford
• Midland Air Museum
• Queensland Air Museum
• East Midlands Aeropark
• Museum of Berkshire Aviation

Specifications (ASMD.3)

See also

References

Notes

Bibliography

• Gunston, Bill. World Encyclopedia of Aero Engines. Cambridge, England. Patrick Stephens Limited, 1989.

External links