Park Royal

At the turn of the century Park Royal was the site of the Royal Agricultural Society Show (1903-6) and later used as an airfield from (1909 – 13). During the War, the site was taken over as a munitions factory and then developed for industry including a factory for the assembly of Renault cars. During the second world war the London Acton main works of D Napier & Son needed to expand and part of the Renault site was acquired for the construction of engine test houses on Coronation Road.

These test houses known as Park Royal 1 (PR1) allowed prolonged testing of the Sabre engine since it was more out of town and could be better tolerated than in the middle of Acton Vale on Acton High Street. The Napier Board minutes for 1st April 1943 state that the progress of the erection of development Test Houses on the Renault site at Park Royal was reported.  After the war the Coronation Road test houses were used for testing all Napier’s engine production including the Napier Naiad, Gazelle and Eland gas turbine and turboprop engines, Napier Nomad compound aero engine and the Napier Deltic.

The image below shows the Coronation  Road site with the five engine test houses and a Sabre engine mounted on an English Electric regenerative test bed.

Napier PR1 site after R-R takeover
 Napier Sabre mounted on EE regenerative test Coronation Road Test House

Across the railway line and the A40 was Mansfield Road where the Company built a precision investment foundry, known as PR2.  This site also included a blade shop and the Napier apprentice school.   The blade shop manufactured some of the most advanced gas turbine engine blades of the time including the blades for all of Napier’s gas turbine engines

Adjacent to Mansfield Road was Alliance Road, where the Napier Development Test House (DTH) was also located.  The images below show the Napier Deltic T9-29 development turbocharged Napier Deltic engine and the Napier Nomad engine in the Development Test House.

Napier turbocharged T9-29 Deltic engine under test
Napier Nomad II in the Development Test House
Wartime Workshops
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