The Wright J65 was an axial-flow turbojet engine produced by Curtiss-Wright under license from Armstrong Siddeley. A development of the Sapphire, the J65 powered a number of US designs.

Design and development

Curtiss-Wright purchased a license for the Sapphire in 1950, with plans to have the production lines running in 1951. However a series of delays due to design changes by Curtiss-Wright, such as substituting the Sapphire's machined midsection solid forged diffuser frame with a fabricated one of welded nodular iron,"World Encyclopedia of Aero Engines - 5th edition" by Bill Gunston, Sutton Publishing, 2006, p.249 led to its service introduction slipping two years. The fabricated assembly, a more practicable production job with about one fifth the cost, was subsequently adopted for the Sapphire.

Another change addressed the Sapphire's only major problem. The Sapphire was found to work well through the entire RPM range without the compressor stalling, which allowed it to dispense with inlet guide vanes or other solutions found on contemporary designs. However, in service it was found that while pressure was maintained even at low speeds and RPM, the first stages were stalling and this was causing significant vibration and fatigue issues. Wright solved this by adding inlet ramps that closed off the outer portions of the intake at low RPM. Armstrong Siddeley evaluated this for the UK Sapphires, but adopted a different solution instead.

By service introduction, the Pratt & Whitney J57 was on the market and took many of the J65's potential sales. Nevertheless, along with the Martin B-57 Canberra, its original application, the J65 went on to power versions of the North American FJ-3/4 Fury, Douglas A-4 Skyhawk, Republic F-84F Thunderstreak, and the two Lockheed XF-104 Starfighter prototypes. Problems Grumman had with the engine in the F11F Tiger, particularly below-spec afterburning thrust, caused them to specify the General Electric J79 for the Grumman F11F-1F Super Tiger."Grumman's Mach-2 International F11F-1F Supertiger" Corwin Meyer, Naval Fighters Number Forty-Four, Steve Ginter 1998, , p.1

As part of an expansion in defense contracts, Buick also built J65s. Its version of the engine, the J65-B-3, was approved for use by the U.S. Air Force in 1953. Components were produced by subcontractors including Oldsmobile, which built the compressor and turbine rotor assemblies; Harrison Radiator, which built the combustion chamber and tailcone; and Brown-Lipe-Chapin, which built the turbine stator blades and compressor stator assemblies. Final assembly was carried out in a portion of a purpose built plant in Willow Springs, Illinois.

Wright T49

A turboprop version of the J65 (Sapphire) was developed by Curtiss-Wright as the Wright T49, and a commercial derivative, the Wright TP51A2 was also designed. The T49 first ran in December 1952 at , followed by flight testing in a Boeing XB-47D test bed from 26 August 1955. By this time however, the market for the engine had vanished."World Encyclopedia of Aero Engines - 5th edition" by Bill Gunston, Sutton Publishing, 2006, p.249

Variants Thrust given in foot-pounds (lbf) and kilonewtons (kN). J65-W-1 J65-W-2 , similar to -1, United States Navy (USN) variant, powered North American FJ-3 Fury J65-W-3 , powered the Republic F-84F Thunderstreak J65-B-3 similar to -1, production by Buick Motor Division of General Motors Corporation, 3,343 built J65-W-4 , powered North American FJ-3 Fury, two North American FJ-4 Fury prototypes J65-W-4B J65-W-5 J65-W-6 / with afterburner, powered the Lockheed XF-104 Starfighter J65-W-7 J65-W-8 at 8,300 rpm dry / with afterburner, powered Grumman F11F-1 / F-11A Tiger J65-W-11 J65-W-12 J65-W-16 J65-W-16A , powered the North American FJ-4 / F-1 Fury J65-W-16C J65-W-18 -16A with reheat J65-W-20 , powered Douglas A4D-2N / A-4C Skyhawk

Applications J65

Douglas A-4 Skyhawk Grumman F-11 Tiger Martin B-57 Canberra Lockheed XF-104 North American FJ-3 Fury North American FJ-4 Fury Republic F-84F Thunderstreak

T49 Boeing XB-47D (T49 testbed)

Specifications (J65-B)

See also

References Footnotes

Notes

Bibliography

External links

A 1952 advert for the Sapphire/J 65 "Anglo-American Jewel - Engineering Details of the Wright J65 Sapphire Revealed" - a 1954 Flight article on the J65