Rolls-Royce RB.44 Tay
Pratt & Whitney J48

The RB.44 Tay was developed from the Nene engine of 1945. Like the Nene, the Tay was made famous by license-built versions built outside the United Kingdom. The Tay was built by Pratt & Whitney as the J48 and by Hispano-Suiza as the Verdon.
Over 4,000 P&W J48s were produced between 1949 and 1959.


  • J48-P-5A: 8,750 lb (38.9 kN) thrust
  • J48-P-6A: 6,250 lb (27.8 kN) thrust
  • J48-P-8A: 7,200 lb (32.0 kN) thrust


  • Centrifugal-flow turbojet
  • Mass flow: 115 lbs/sec

used by

  • Grumman F9F Panther
  • North American F-93
  • Lockheed F-94 Starfire