Napier Javelin

HOME COMPANY HOME PRODUCTS HOME AERO ENGINES HOME Turbine

In 1927 Montague Napier reached an agreement with  Major Frank B. Halford to act as a consultant designer for D Napier & Son.  Napier was determined to enter into the the technology of air-cooled engines and Halford was a natural choice.  Both Montague Napier and Halford believed that this was the way ahead due to its lightness and having push rod operated overhead valves.  Napier's remit to Halford was for an air-cooled engine between 6.6 litres and 11.8 litres.  

 

The Napier Javelin was the first engine Halford designed for the Company.  This was similar to the ‘Cirrus Hermes’ and the ‘De Havilland Gypsy’, having an inverted six cylinder 8.2 litre giving 170bhp at 2,100rpm.

 

The engine was a marginal success powering a number of Percival light aircraft such as the Gull IV and a racing Mew Gull.  During the 1930’s this engine had earned a reputation for cutting out on takeoff, a problem that always remain unsolved.

Rocket Lion Dagger Culverin Sabre Rapier Cub Piston

In-Line Engine

Design E97T  1931   Test Engine

4-cylinder 4.1/2" bore x 5.1/4" stroke  100 bhp

 

Design E97   1931   Javelin III

6-cylinder 4.1/2" bore x 5.1/4" stroke  170 bhp

Where to see:

    NMSI Store, Wroughton, Nr. Swindon

    NPHT collection

    RAF Museum Hendon

   

CONTACT NPHT