Armstrong Siddeley Stentor

The Armstrong Siddeley Stentor, latterly Bristol Siddeley BSSt.1 Stentor, was a two-chamber HTP rocket engine used to power the Blue Steel stand-off missile carried by Britain's V bomber force.^[1][2] The high thrust chamber was used for the first 29 seconds, after which it was shut down and a smaller cruise chamber was used for the rest of the powered flight.^[3][4][5]

Stentor
Stentor rocket engine showing the large main nozzle (top) and the smaller cruise nozzle (bottom)
Type	Rocket engine
National origin	United Kingdom
Manufacturer	Armstrong Siddeley
First run	c.1960
Major applications	Blue Steel missile

Design and development

It was fuelled by hydrogen peroxide with kerosene.^[1]

The engine incorporated an integral tubular mounting frame which was attached by six lugs to the rear bulkhead of the missile airframe, the complete engine being enclosed in a tube-shaped fairing with the nozzles at the rear.

Applications

• Blue Steel missile

Engines on display

Preserved Stentor engines are on display at the following museums:

• Royal Air Force Museum Cosford
• Midland Air Museum
• The University of Liverpool, in the Department of Engineering foyer.
• South Yorkshire Aircraft Museum, Doncaster
• Newark Air Museum, Nottinghamshire
• Cambridge Science Centre, Cambridge

Specifications

Cut-away Stentor on display at the Royal Air Force Museum Cosford

Data from ^[6]

General characteristics

• Type: two chamber liquid-propellant rocket engine
• Length: 58 in (1,473 mm)
• Diameter: 38 in (965 mm) wide, 44.5 in (1,130 mm) high
• Dry weight: 747 lb (339 kg) including oil and nitrogen
• Fuel: kerosene
• Oxidiser: hydrogen peroxide

Components

• Pumps:

Performance

• Thrust: large boost chamber rated at 24,000 lbf (110 kN)
  smaller cruise chamber rated at 6,000 lbf (27 kN)
• Burn time:
• Thrust specific fuel consumption:
• Specific impulse: ~220 seconds (2.2 km/s)^[7]

See also

Related development

• Bristol Siddeley BS.605

Related lists

• List of aircraft engines

References

1. "Blue Steel and its Engine". Flight. Missiles and Spaceflight. 12 August 1960. pp. 214–215.
2. Millard, Douglas (2001). The Black Arrow Rocket. Science Museum. p. 23-24. ISBN 1 900747 41 3. In early 1956, the government contracted Armstrong Siddeley to develop a second HTP engine, this time for a quite different kind of vehicle called Blue Steel. [...] Blue Steel's engine was called Stentor
3. "Stentor rocket motor". Skomer. Archived from the original on 20 April 2008.
4. "Rocket Engines for Piloted Aircraft". Bristol Siddeley Magazine. 1960.
5. "Blue Steel in Action". Flight: 329. 11 March 1960.
6. S.D.4766B, Vol.1, Sect.4 - July 63
7. Hill, C N (2001). A vertical empire. Imperial College Press. p. 64. ISBN 978 1 86094 267 9. Burning HTP and kerosene, it produced a S.I. around 220.