Grace's Guide is the leading source of historical information on industry and manufacturing in Britain. This web publication contains 140,143 pages of information and 227,382 images on early companies, their products and the people who designed and built them.
1947 Metrovick left the jet engine industry, with some of their design team moving to Armstrong Siddeley which had a turbine development of their own, the ASX, but this was primarily focused on turboprops.
1948 F.9, now renamed the ASSa.5, was first run on 1 October 1948. Initially it developed about 7,500 lbf (33 kN), more than its competitor from Rolls-Royce, the Avon. A number of companies expressed interest in the F.9, and it was considered as either the main or backup powerplant for many late-40s/early-50s British aircraft designs.
It was used on the English Electric P.1.A, prototype of the Lightning, but it was not a happy fit.
Variants with increasing power were developed and tested in aircraft. Afterburners, but of limited performance, were also added
Curtiss-Wright purchased a licence for the Sapphire in 1950, with plans for production in 1951 but a series of delays led to its introduction slipping a full two years, by which point the Pratt & Whitney J57 was on the market and took many of its potential sales.