Blackburne Tomtit

Tomtit
The Shuttleworth Collection's Tomtit seen from the output (propeller) side. Valve pushrods can be glimpsed behind cylinder heads.
Type	Air-cooled V-twin
National origin	United Kingdom
Manufacturer	Burney and Blackburne, Ltd., Bookham, Surrey
First run	c.1922

The Blackburne Tomtit was a 670 cc V-twin aero engine for light aircraft that was designed and produced by Burney and Blackburne Limited. Burney and Blackburne was based at Bookham, Surrey, England and was a former motorcycle manufacturer.

The Blackburne Tomtit engine was developed from Blackburne's motorcycle engines. The first one adapted to aircraft use was the best performing engine at the Lympne light aircraft trials of 1923, despite its lack of refinement. The Tomtit was a modified version of the Lympne 696 cc V-twin, marketed specifically for flight.

The Tomtit could run upright or inverted and was the first British engine to fly inverted, in the ANEC I. The inverted configuration was more common, but the Avro 558 used it in the upright arrangement, and the Avro 560 flew with both upright and inverted Tomtits.

Data from Flight

Douglas Light Aero engines from Kingswood to Cathcart.Page 106 Brian Thorby 2010 Redcliffe Press, Bristol ISBN

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