Tag Archives: Wright Cyclone SGR-1820-G5

14 January 1936

Hoard Hughes with his record-setting Northrop Gamma. (Unattributed)
Howard Hughes with the record-setting Northrop Gamma. (UNLV Special Collections)

14 January 1936: Flying a Northrop Gamma 2G, serial number 11, which he had leased from Jackie Cochran, Howard Robard Hughes, Jr., set a Fédération Aéronautique Internationale (FAI) World Record for Speed Over a Recognized Course (Los Angeles, California, to New York) in 9 hours, 26 minutes, 10 seconds, at an average speed of 417.0 kilometers per hour (259.1 miles per hour).¹ Most of the flight was made at altitudes of  15,000–18,000 feet (4,572–5,486 meters), and Hughes used supplemental breathing oxygen.

Howard Hughes climbs out of the Northrop Gamma at Newark, New Jersey. (UNLV Digital Collection)
Howard Hughes climbs out of the Northrop Gamma at Newark, New Jersey. (UNLV Digital Collection)
Howard Hughes is interviewed at Newark, New Jersey, 14 January 1936.

Jack Northrop had designed and built the Gamma as a long-range cargo and mail plane for Transcontinental and Western Air, Inc. The contract was cancelled, though, and several airplanes became available to other customers. Jackie Cochran purchased s/n 11, which had been completed 15 August 1934, and had it modified by Northrop as a two-place long-distance racer for the 1934 MacRobertson London-to-Australia air race, which she planned to fly with her friend Ted Marshall.

The length of the Gamma varied from 29’10” to 31’0″, depending on engine and cockpit configuration. The wingspan was 48’0″.

The Northrop Gamma 2G, NC13761, after modification to install a liquid-cooled Wright SGV1570F4 V-12 engine, 9 September 1934. (SDASM Archives)
The Northrop Corporation Gamma 2G, NC13761, after modification for the MacRobertson Race, 29 September 1934. (The Northrop Corporation)
The Northrop Gamma 2G, NC13761, after modification to install a liquid-cooled Wright SGV1570F4 V-12 engine. (SDASM Archives)

The Gamma’s original engine was replaced with a liquid-cooled, supercharged, 1,570.381-cubic-inch-displacement (25.734 liters) Wright Aeronautical Division Conqueror SGV1570F4 (also known as the Curtiss Conqueror), a DOHC 60° V-12 engine rated at 745 horsepower at Sea Level. The engine drove a two-bladed propeller. The Gamma had 7 fuel tanks: 3 in each wing and 1 in the fuselage. Total capacity was 486 gallons (1,840 liters) of gasoline and 29 gallons (110 liters)of lubricating oil. A second fuselage tank was later added, bring the total fuel capacity to 586 gallons (2,218 liters). The Gamma 2G had an empty weight of 4,727 pounds (2,144 kilograms) and a maximum gross weight of 8,037 pounds (3,646 kilograms). The modified airplane was inspected and a temporary commercial registration, NC13671, was approved 29 September 1934.

While being ferried to New York by Jackie and her new copilot, Royal Leonard, problems with the engine’s supercharger forced them to land in Arizona. Cochran continued east by airliner while Leonard and a Curtiss-Wright mechanic continued east in the Gamma. Flying on the night of 1 October 1934, a continuing problem with the supercharger forced them to make an off-field landing near Tucumcari, New Mexico, using light from dropped flares. The Gamma was seriously damaged and had to be returned to Northrop for repair.

Northrop Gamma 2G NX13761 after installation of the air-cooled Pratt & Whitney Twin Wasp, Jr. SA1-G 14-cylinder radial engine. (SDASM Archives)

The airplane’s temporary registration was suspended. A section of the wing and the forward lower half of the fuselage were replaced, provisions for installing a Pratt & Whitney radial engine were made, and the rear cockpit was removed. (Cochran’s plans for the MacRobertson Race had to be revised,² so she had the airplane modified for the Bendix Trophy Race.) The repairs and modifications were completed 30 November 1934.

Jackie Cochran’s Northrop Gamma NX13761 after radial engine installation, photographed at Clemenceau, near Cottonwood, Arizona, circa 1935. (Ruth Reinhold Aviation Collection, Arizona Memory Project RRA-AMP107)

The “re-modified” Gamma 2G was now powered by an air-cooled, supercharged, 1,534.943-cubic-inch-displacement (25.153 liters) Pratt & Whitney Twin Wasp Jr. SA1-G 14-cylinder radial engine with a three-bladed Hamilton Standard controllable-pitch propeller. The SA1-G was rated at 700 horsepower at 2,500 r.p.m. at 6,500 feet (1,981 meters). The engine could be ordered with a 3:2 or 4:3 gear reduction ratio.

Jackie Cochran flew the Gamma in the 1935 Bendix Trophy Race, but, approaching severe weather over the Grand Canyon, landed the airplane and did not finish the race.

The official ownership history of the Gamma is murky. The original application for a Department of Commerce Aeronautics Branch license specified the owner as The Northrop Corporation. On 4 January 1935, Northrop’s registration was cancelled by the Department of Commerce because, “Aircraft not inspected for relicensing.”

Jackie Cochran with the Northrop Gamma 2G, circa 1936. Photographed by Toni Frissell.

When Jackie Cochran requested registration in her name, she failed to submit a Bill of Sale with her application. After repeated written requests by the Bureau of Air Commerce to submit a bill of sale went unanswered, her application for a restricted registration for the airplane was cancelled, 9 January 1936. J Carroll Cone, Assistant Director of Air Commerce (Air Regulation) informed her in writing: “The status of this aircraft is unlicensed and unidentified, according to our records. Any operation thereof would be in violation of the Air Commerce Regulations and subject the offender to the civil penalty provided therefor.”

Finally, a Bill of Sale from The Northrop Corporation, dated 30 November 1935, was provided to the Aeronautics Bureau. It said that Northrop had sold the airplane to Cochran, “for and in consideration of ten dollars ($10.00)”.

Meanwhile, Howard Hughes had seen the Gamma and wanted to buy it. Jackie Cochran tells how Howard Hughes acquired the airplane:

One night about 11:30 I was exhausted in my hotel room and the telephone rang. . .

“Jackie,” the voice says, “this is Howard.”

“Howard who?” I say, still sleepy and getting frustrated.

“Howard Hughes,” the man says.

“Howard who?” I ask again.

“Howard Hughes,” he repeats.

. . . We argued about who he was a bit more. Finally, he says, “I want to buy your airplane.”

I’m thinking that this is an incredible conversation. “It’s not for sale, Howard,” I reply. “I’m going to fly it in the Bendix.”

“I don’t want to fly it in the Bendix,” he answers. “I want to fly it cross-continental.”

“So do I,” I say.

Howard Hughes and I negotiated over the Northrop Gamma for about four weeks. . . Howard wanted my Northrop so badly, but it would break my heart to consider handing over my rights to it. . . when he offered to rent it, with an option to buy, I caved in. . . .

Jackie Cochran: An Autobiography, by Jacqueline Cochran and Maryann Bucknum Brinley, Bantam Books, New York, 1987, at 152–153.

When Hughes took possession of the Gamma 2G, he had the Pratt & Whitney engine replaced with a 1,823.129 cubic-inch (29.785 liter) Wright Cyclone SGR-1820-G5 nine-cylinder radial engine, and a three bladed-Hamilton Standard constant-speed propeller with a diameter of 11 feet, 3 inches (3.429 meters). The engine used a bell-shaped cowling similar to that of Hughes’ H-1 Racer. The engine had a Normal Power rating of 830 horsepower at 2,100 r.p.m to 4,300 feet (1,311 meters), and 930 horsepower for Takeoff. This engine did not yet have government certification. Three additional fuselage tanks were installed, increasing the Gamma’s fuel capacity to 690 gallons. Hughes did not submit the Gamma for Department of Commerce inspection and licensing. It was not approved in the new configuration.

Jackie Cochran took the Gamma back from Hughes and had the Twin Wasp Jr. reinstalled, and submitted a new application for registration 31 March 1936. This was approved 28 April 1936, and the Gamma received a restricted registration, NR13761. It was damaged beyond repair after an emergency landing, 10 July 1936.

The Northrop Gamma 2G, NR13761, at Newark, New Jersey, 14 January 1936. (UNLV Libraries Digital Collection)

¹ FAI Record File Number 13237

² With Northrop unable to repair the airplane in time for the MacRobertson Race, at the last minute Jackie Cochran entered with a different airplane (a Granville Brothers Gee Bee R-6H).

© 2017, Bryan R. Swopes