General Electric Aircraft Engines

By Judy Rumerman, U.S. Centennial of Flight Commission

General Electric Company (GE) was incorporated in 1892, when it acquired the assets of The Edison General Electric Company, founded by Thomas Alva Edison, and two other electric companies. Although the company is best known for its consumer products, jet aircraft engines comprise a significant portion of its revenue. Its engine division has been called GE Aircraft Engines since 1987.

The company's earliest activities focused on trying to develop a turbine engine to generate electric power. In 1903, GE succeeded in installing the world's largest steam turbine generator in Chicago to generate electric power to replace a reciprocating engine that was ten times its size. This was the beginning of practical turbine technology.

During the first four decades of the 20th century, GE's engine division concentrated primarily on developing and building engine "boosters," or turbosuperchargers. These "turbos" capture the exhaust gases produced by a piston engine and use them to drive a turbine. The turbine, in turn, drives a supercharger, which acts as an air compressor and delivers additional air to run the engine. This boosts the engine's power and is particularly useful at higher altitudes where the air is thinner. Sanford A. Moss, who had come to GE early in the century as a new Ph.D., had developed the technology for the Army. The turbos enabled engine-makers to develop engines that powered aircraft to higher altitudes. Turbos were used on the B-17 Flying Fortress, allowing it to fly at 25,000 feet (7,620 meters), as well as on several other World War II aircraft. In 1940, Moss became the first GE engineer to receive the prestigious Collier Trophy for "outstanding success in high altitude flying by the development of the turbosupercharger."

In 1940, the United States, although neutral, was beginning to support the Allies. GE started expanding to meet their defense needs and built two new plants for turbo production. By mid-1941, GE turbos were in mass production in four states and were seeing combat service with Allied Air Forces under the Lend-Lease program.

Moss also led GE in developing its early gas turbine engine, which in America of the late 1930s, was still experimental and confined to the laboratory. Britain and Germany, on the other hand, had made steady progress in use of the turbine as a primary source of propulsion. Both Germany's Hans von Ohain and Britain's Frank Whittle had independently invented the turbojet engine in the mid 1930s.

Finally in 1941, GE received its first contract from the U.S. Army Air Corps to build a gas turbine engine based on Frank Whittle's design. Six months later, on April 18, 1942, GE's engineers successfully ran their I-A engine—the first jet engine to operate in the United States. On October 1, 1942, a Bell P-59 powered by General Electric I-16 turbojet engines made its first flight at California's Muroc Army Air Field. The jet age had come to America. The company followed shortly with the J-31, the first turbojet produced in quantity in the United States.

Two years later, in June 1944, the Air Corps' first operational fighter, the Lockheed P-80 Shooting Star, flew powered by a J33/I-40 engine rated at 4,000 pounds (17,793 newtons) thrust. In 1947, it would set a world speed record at 620 miles per hour (998 kilometers per hour).

The J33 became an important wartime engine, and the U.S. Air Force needed quantity production quickly. The Air Force licensed J33 production to the Allison division of General Motors. Allison would go on to built thousands of the GE-designed engine while GE built only 300. Production of both the J33 and its follow-on J35, designed by GE, went to Allison.

GE began developing the J47 from the earlier J35. The J47 would power several of the new front-line military aircraft, including the F-86 Sabre Jet, which set a new world's speed record of just under 671 miles per hour (1,080 kilometers per hour) in September 1948. Demand for the engine soared during the Korean War, and more than 35,000 were delivered by the end of the 1950s. During 1953-54, J47 production reached a rate of 975 engines per month. The J47 was also the first turbojet certified for civil use by the U.S. Civil Aeronautics Administration and the first to use an electrically controlled afterburner to boost its thrust. The engine spanned 30 years of operational service before it was retired in 1978.

General Electric Jet Engines N684FE - a Fedex Airbus A300 freighter with General Electric CF6-80 Series engines is seen over Denver International in September 2003. Image courtesy of AirNikon. Find more of his photos at Airliners.net

In February 1949 GE reopened a plant near Cincinnati, known as Evendale, for J47 production. In only 20 months, Evendale grew from 1,200 to 12,000 employees and manufacturing space tripled. Evandale would later become GE Aircraft Engines' world headquarters.

The J47 was inadequate for the new series of supersonic fighters because, at high speeds, the front compressor stages would pull in more air than then rear ones could handle, leading to compressor stall. In 1952, GE's chief of engine development Gerhard Neumann began developing the J79 turbojet engine. It had movable stator vanes in the compressor that helped modulate the amount of air that the compressor would pull in. This solved the problem of compressor stall and permitted flight at speeds of Mach 2 and greater. More than 17,000 J79s were built over 30 years, powering aircraft such as the F-104 Starfighter and F-4 Phantom II. On the Convair 880 airliner, the CJ805 derivative of the J79 engine marked GE's entry into the civil airline market.

The 1950s and 1960s saw the J93, the first engine to operate at Mach 3, power the experimental XB-70 bomber; a nuclear-powered turbojet; and the addition of a fan to the rear of the CJ805 to create the first turbofan engine for commercial service for the Convair 990. In August 1965, the Air Force picked GE's TF39 to power its C-5 Galaxy cargo plane. This was the world's first high bypass turbofan to enter service. Another success of the period was the J85 turbojet engine that powered the Northrop F-5 Freedom Fighter, which was used by more than 30 nations.

Advances in compressor, combustor and turbine knowledge in the 1960s led to the F101 engine, selected for the B-1 bomber. In 1984, the U.S. Air Force selected GE's F110 engine, based on the F101 design, as one of the engines for the F-16C/D fighter aircraft. The F110 also powered F-16s worldwide as well as Japan's single-engine F-2 fighter aircraft and the U.S. Navy's F-14B/D Super Tomcat fighter. A derivative of the F110, the F118, powered the B-2 bomber.

Also in the 1980s, the GE F404 engine for the F/A-18 Hornet entered production. As of the late 1990s, more than 3,700 units powered the aircraft of several military services worldwide, including the F-117 Stealth fighters. F404 derivatives also powered Sweden's JAS 39 Gripen and Singapore's A-4S Super Skyhawk.

GE's commercial engines of the 1970s built on the technology of the TF39 military engine of the 1960s. Beginning in the early 1970s, the CF6-6 high bypass turbofan engine powered the Douglas DC-10. By the 1980s, the CF6 family of engines was powering wide-body aircraft, including the Boeing 747 and 767, the Airbus A300 and A310, and the McDonnell Douglas MD-11. By the late 1990s, more than 5,500 CF6 engines were in service. A CF6-80C2 engine powers Air Force One.

Around the same time that GE was developing its CF6 family, it entered into a collaboration with SNECMA, the leading French aircraft engine manufacturer. Formally established in 1974 CFM International wanted to gain a share of the short- to medium-range aircraft engine market. The company received its first order in 1979, when the CFM56-2 turbofan engine was selected to re-engine DC-8 Series 60 aircraft, renamed Super 70s. Then the U.S. Air Force selected the military version of the CFM56-2, designated the F108, to re-engine its fleet of KC-135 tanker aircraft. Since then, GE and SNECMA CFM56 engines have powered commercial aircraft for the Boeing Classic 737-300/-400/-500 series, Airbus Industrie A318, A319, A320, and A321, and the long-range, four-engine Airbus A340. The CFM56-7, powerplant for the Boeing Next-Generation 737-600/-700/-800/-900 series, was launched in late 1993. In the second half of the 1990s, more than 3,500 CFM engines were delivered worldwide.

Note: This article was commissioned by and first appeared on NASA's U.S. Centennial of Flight web site. It appears here with permission. We gratefully acknowledge both the author and NASA.