The CFM International CFM56 (US military designation F108 ) series are a family of high-bypass turbofan engines made by CFM International with a thrust range from 18,500 to 34,000 lb f (82 to 151 kN). CFM International is a 50-50 joint company of SNECMA, France and GE Aviation, USA. Both companies are responsible for producing various components and each has their own final assembly line. GE is responsible for the high pressure compressor, combustor and high pressure turbine, and SNECMA is responsible for the fan, low pressure turbine, the gearbox and the exhaust. The engines are assembled by GE in Evendale, Ohio, USA and by SNECMA in Villaroche, France.
The CFM56 is one of the most prolific engine types in the world with nearly 20,000 built. The engine is most widely used on the Boeing 737. It is also the sole powerplant of the A340-200/-300, and the CFM56 (designated F108) replaced the Pratt & Whitney JT3D engines on the US KC-135 Stratotanker in the 1980s to create the KC-135R. The engine is also used on some on some Airbus A320s. As of September 2009, the CFM56 had flown over 450 million cumulative hours (the equivalent of more than 51,000 years) across all platforms.
Development
In the late 1960s, it was becoming clear that the the next generation of commercial engines would be high bypass ratio engines in the "10-ton" (or 20,000 lbf) class. SNECMA was the first to act, and began searching for a partner with commercial experience (they had mostly built military engines to this point) to design and build the engine. After considering Pratt & Whitney, Rolls-Royce, and GE Aviation, SNECMA selected GE. The two main reasons GE was likely selected was that they needed an engine in this market class (Pratt & Whitney dominated the commercial market at this point), and that SNECMA had experience with them, collaborating on the production of the CF6-50 turbofan for the Airbus A300.
A major reason that GE was so interested in the collaborative project, rather than building a 10-ton engine on their own, was that the SNECMA project was the only source for development funds for an engine in this class at the time. GE was initially considering only contributing technology from its CF6 engine rather than its much more advanced F101 engine, developed for the B-1 Lancer supersonic bomber. However the US Air Force announced its Advanced Medium STOL Transport (AMST) project in 1972 which included funding for the development of a 10-ton engine. GE was now faced with a dilemma - should they build two 10-ton engines, one with "limited" technology with SNECMA and one with "advanced" technology on their own, or should they try to develop a single, advanced, engine? Worried that if they did not win the Air Force contract with the advanced engine (in which they were competing with Pratt & Whitney and GM), they would be left with only the "limited" engine in their portfolio, GE decided to apply for an export license for the F101 core technology.
Export issues
In 1972, GE applied for an export license for its F101 core technology as GE's primary contribution to the "10-ton" engine project. However, the United States Department of State's Office of Munitions Control recommended the rejection of the application on national security grounds, specifically because the core technology was an aspect of a strategic national defense system (the B-1 bomber), it was built with Department of Defense (and therefore American taxpayer) money, and that exporting the technology to France would limit the number of American workers on the project. The official decision was made in a National Security Decision Memorandum signed by the National Security Advisor Henry Kissinger on 19 September 1972.
While national security concerns were cited as the grounds for the rejection, it was reported that high level politics played an important role as well. The project, and the export issue associated with it, was considered so important that French President Georges Pompidou appealed directly to President Richard Nixon in 1971 to approve the deal, and that Henry Kissinger brought the issue up with President Pompidou in a 1972 meeting. GE reportedly argued at the highest levels that having half of the market was better than having none of it, which they argued would happen if SNECMA pursued the engine on their own without GE's contribution. However, Nixon administration officials feared that this project could be the beginning of the end of American aerospace leadership.
There was also speculation that the rejection may have been, in part, retaliation for French involvement in convincing the Swiss not to purchase American-made A-7 Corsair II aircraft that had been competing against a French design (in the end the Swiss decided not to buy either of the aircraft).
1973 Nixon/Pompidou meeting
Despite the export license being rejected, both the French and GE continued to push the Nixon Administration for permission to export the F101 technology. Efforts continued throughout the months following the rejection, culminating in the engine being an agenda topic during the 1973 meeting of Presidents Nixon and Pompidou in Reykjavik. Discussions at this meeting resulted in an agreement, allowing the development of the CFM56 to proceed. At the time it was reported that the agreement was based around assurances that the core of the engine, the part GE was developing from the military F101, would be built in the United States and then transported to France in order to protect the sensitive technologies. In addition, documents declassified in 2007 revealed that a key aspect of the CFM56 export agreement was that French government agreed not seek tariffs against American aircraft being imported into Europe.
CFM International
With the export issue now settled, GE and SNECMA worked out the agreement that founded CFM International (CFMI), which was the 50-50 joint venture that would be responsible for producing and marketing the 10-ton engine, the CFM56. The venture was officially founded in 1974. The two primary roles for CFMI were to manage the program between GE and SNECMA and to market/sell/service the engine at a single point of contact for the customer. CMFI was responsible for the day-to-day decision making for the project, while major decisions (developing a new variant, for example) required the go-ahead from GE and SNECMA management.
The CFMI Board of Directors is split evenly between SNECMA and GE (five members each). There are two Vice Presidents, one from each company, who support the President of CFMI. The President tends to be drawn from SNECMA and sits at CFMI's headquarters near GE in Cincinnati, Ohio.
The work split, in general terms, gave GE responsibility for the high pressure compressor (HPC), the combustor, and the high pressure turbine (HPT), while SNECMA was responsible for the fan, the low pressure compressor (LPC), and the low pressure turbine (LPT). SNECMA was also responsible for the initial airframe integration engineering, mostly involving the nacelle design. SNECMA was initially responsible for the gearbox, but shifted that work to GE when it became apparent that it would more efficient for GE to assemble that component along with their other parts.
Early development
Once the export agreement was settled, development work on the CFM56 began in earnest, even before CFM International was formally created. While most work proceeded smoothly, the international arrangement led to some unique working conditions. For example, both companies had assembly lines, so some of the engines were assembled and tested in the US, and some were assembled and tested in France. Those engines assembled in France had to work around the initially strict export agreement, which meant GE's core was built in the US, then shipped to the SNECMA plant in France, and then placed in a locked room that the President of SNECMA wasn't even allowed in. The SNECMA components (the fore and aft sections of the engine) are brought into the room, where GE employees mounted them to the core. Then the assembled engine is taken out to be finished.
Despite challenges like this, work on the first CFM56 engine proceeded, and first ran at GE in June 1974. The second engine also first ran at GE in October 1974. It was then shipped to France in December, and first ran there on December 13 1974. These first CFM56 engines were considered "production hardware", not just test articles, and were designated as CFM56-2 engines, which was the first variant of the CFM56.
Three years later, in February 1977, the engine flew for the first on the McDonnell Douglas YC-15, an entrant in the Air Force's Advanced Medium STOL Transport competition. It replace one of the 4 Pratt & Whitney JT8D engines the aircraft used. Soon after the engine first flew on the YC-15, the next CFM56 was mounted on a Sud Aviation Caravelle at the SNECMA flight test center in France. This engine had a slightly different configuration (a long bypass duct with mixed exhaust flow, rather than a short bypass duct with unmixed exhaust flow), and was the first to include a "Thrust Management System" to maintain engine trim.
First customers
After testing the engine for several years, both in the air and on the ground, CFM International was really looking for customers outside of a possible AMST contract. The main targets were re-engine contracts for the Douglas DC-8 and the Boeing 707, includi
GE Wall Ovens - Single Wall Oven, Double Wall Oven from GE Appliances
Single and Double Wall Ovens from GE Appliances. GE offers a variety of single wall ovens, double wall ovens, and single-double wall ovens in multiple sizes. Some models include ...
GE Microwaves - Microwave oven, Microwave convection oven from GE ...
Microwaves from GE Appliances. GE microwave ovens, microwave convection ovens, over the range microwaves, counter top microwaves, advantium and spacemaker products offer a variety ...
GE Range/Stove/Oven Parts from RepairClinic.com
GE Range/Stove/Oven Parts in stock. 1000000 appliance parts ship on time or the order is free! Return any part. Call 7 days, 8am to Midnight.
GE Oven/Range Parts - GE Oven/Range and Stove OEM Repair Parts at ...
GE, GE Oven/Range, Cheap Appliance Parts ... GE Oven/Range Parts - GE Oven/Range and Stove OEM Repair Parts at Cheap Appliance Parts
GE Stove / Oven / Range Part Electric Ovens - GE Part Stove, Gas GE ...
Midwest Appliance Parts stocks all GE Stove / Oven / Range Parts - GE Part Stove, Gas GE Part Stove, Electric GE Part Stove, GE Part Replacement Stove, GE Part Profile Stove, GE ...
GE Oven Parts - Replacement Appliance Parts
GE Oven Parts. Full Range GE Oven Parts Available Online. Select from a large inventory of GE oven parts in stock. Find thousands of parts that will let you practically rebuild an ...
GE Double Ovens
GE Double Ovens - GE double built-in ovens offer the latest in cooking technology and ensures superb results. Select between 30" and 27" wide ovens in stainless steel, black, white ...
GE Oven Parts | GE Parts
Buy GE oven parts to repair your GE oven at PartSelect Appliance Parts. Great prices on all GE parts you need to help you repair your oven quickly and easily. Same-day shipping and ...
GE Ovens
GE Ovens - Choose from a wide selection of GE single, double, combination and Advantium Speedcook Ovens. The GE and GE Profile ovens with Trivection technology, give everyday cooks ...
Fast Moving GE Brands Range and Oven Parts
Search and order OEM exact fit GE brands range and oven parts you need. Same Day Shipping from 33 locations