History

The Wright J-6 series of “Whirlwinds” began in the works of Charles A. Lawrance’s Lawrance Aero-Engine Corporation with its 787 cubic inch (13.12 L) J-1 which produced 200 hp. These were the first radial engines in production in the USA and were built in quantity for the US Navy, which had adopted air cooled radials as its standard for shipboard aircraft. In May of 1923 Wright bought Lawrance Aero-Engine and installed Charles Lawrance as Vice President of Wright Aeronautical Corporation. Wright continued development of the J series engines. In 1926 Wright introduced the ninth significant change in the series as the J-6-9 nine-cylinder radial engine. Seven and five cylinder versions were also available as the J-6-7 and J-6-5.

Specifications:

Model: J-6-9 Whirlwind (R-975)
Displacement: 975 cubic inches (15.98L)
Power: 300 hp @ 2,000 RPM (increased to 450 hp later)
Weight: 550 pounds (250 Kg)

Applications:

The J-6-9 Whirlwind was used on myriad airplanes around the world. It is not practicable for me to provide a complete listing of applications here. I doubt, in fact, that such a listing is possible. Here then are a few: Fairchild F 51, Ford 4-AT-E, 6-AT-A/AS, Keystone-Loening Commuter, Ryan B-5 Brougham, Curtiss Kingbird, Lockheed Vega 5, travel Air 6000, Fokker F VII/3m and Bellanca Pacemaker. Check your own references for others.

The Parts

There are two offerings available:
· Engine with single-outlet exhaust collector and propeller.
· Engine with double-outlet exhaust collector and propeller.
The propeller is a ground adjustable 9’ Hamilton, later Hamilton-Standard unit. Be sure to specify which exhaust collector you require when ordering. Each offering costs $7.50.

Ordering, shipping and other details are set out on Khee-Kha’s web site

Conclusion

As usual from Khee-Kha, these parts are accurate in detail and are cast with fine, crisp precision free of bubbles and voids. The photos here invite your close examination.

References:

• World Encyclopaedia of Aero Engines: Bill Gunston, Patrick Stevens, ltd., UK, 1998, ISBN 1-85260-597-9.

• A History of Aircraft Piston Engines: Herschel Smith, McGraw-Hill, USA, 1994, ISBN 0-89745-079-5.

• The Development of Piston Aero Engines: Bill Gunston, Patrick Stevens, Ltd., UK, 1994, ISBN 1-85260-385-2.