[2], Most variants of the CFM56 feature a single-annular combustor. 25 August 1990. [42], The CFM56-7 powers the Boeing 737 Next Generation series (737-600/-700/-800/-900). With those benefits in mind, the United States Navy selected the CFM56-2 to power their variant of the Boeing 707, the E-6 Mercury, in 1982. [nb 2] Only the high-power CFM56-5C, designed for the Airbus A340, has a mixed-flow exhaust nozzle. NTSB No: DCA-06-MA-009. The major changes included a modification to the fan/booster splitter (making it more difficult for hail to be ingested by the core of the engine) and the use of an elliptical, rather than conical, spinner at the intake. Several fan blade failure incidents were experienced during the CFM56's early service, including one failure that was a cause of the Kegworth air disaster, and some variants of the engine experienced problems caused by flight through rain and hail. CFMI modified the engines by adding a sensor to force the combustor to continuously ignite under these conditions. [62] The redesigned fan blades were installed on all CFM56-3C1 and CFM56-3B2 engines, including over 1,800 engines that had already been delivered to customers. Samuelson, Robert (1972). The new fan is primarily derived from GE's CF6-80 turbofan rather than the CFM56-2, and the booster was redesigned to match the new fan. The CFM56-2 comprises a single-stage fan with 44 blades, with a three-stage LP compressor driven by a four-stage LP turbine, and a nine-stage HP compressor driven by a single-stage HP turbine. No further engine modifications were recommended.[60]. [47], The CFM56 fan features dovetailed fan blades which allows them to be replaced without removing the entire engine, and GE/SNECMA claim that the CFM56 was the first engine to have that capability. [nb 3][17], After testing the engine for several years, both in the air and on the ground, CFMI searched for customers outside of a possible AMST contract. After the fan blade failed, the pilots mistakenly shut down the wrong engine, resulting in the damaged engine failing completely when powered up after descent. Derived from the CFM56-2 and CFM56-3 families, the -5A series produces thrusts between 22,000 and 26,500 lbf (98 kN and 118 kN). "CFM56-2 Technology". /* 160x600, created 12/31/07 */ The problem has been long-standing. [5], A major reason for GE's interest in the collaboration, rather than building a 10-ton engine on their own, was that the SNECMA project was the only source of development funds for an engine in this class at this particular time. [44], The CFM56-2 series is the original variant of the CFM56. Contemporary reports state that the agreement was based on assurances that the core of the engine, the part that GE was developing from the military F101, would be built in the U.S. and then transported to France in order to protect the sensitive technologies. They work by actuating a door that pivots down into the bypass duct, both blocking the bypass air and deflecting the flow outward, creating the reverse thrust. By January 2010, the CFM56 had flown more than 470 million cumulative hours (equivalent to over 53,000 years). CFM-56 Jet Engine Joint Development (1973). Several fan blade failure incidents were experienced during the CFM56's early service, including one failure that was noted as a cause of the Kegworth air disaster, while some variants of the engine experienced problems caused by flight through rain and hail. SNECMA, who had mostly built military engines until then, was the first company to seek entrance into the market by searching for a partner with comm… Like other aspects of the program, international politics played their part in this contract. [4] As design evolved HPC design improved through better airfoil design. It also powers the military versions of the Next-Generation 737, the C-40 Clipper, the P-8 Poseidon, and Boeing 737 AEW&C.[59]. The engines have also suffered, periodically, from thrust instability events tentatively traced to Honeywell's hydromechanical unit. The low-pressure turbine (LPT) features four stages in most variants of the engine, but the CFM56-5C has a five-stage LPT. The new variant was listed as the 707-700. The new components also reduced engine wear, lowering maintenance costs by about 5%. In 1987, a double flameout occurred in hail conditions (the pilots managed to relight the engines), followed by the TACA Flight 110 incident in 1988. The engine (CFM56-5A and 5B) is also fitted to Airbus A320 series aircraft. Article Id: After the fan blade failed, the pilots mistakenly shut down the wrong engine, resulting in the damaged engine failing completely when powered up for the final approach. (2007). [47], The CFM56 fan features dovetailed fan blades which allows them to be replaced without removing the entire engine, and GE/SNECMA claim that the CFM56 was the first engine to have that capability. CFM International Press Release. These first engines were considered "production hardware" as opposed to test examples and were designated as the CFM56-2, the first variant of the CFM56. Airbus A320s were to use this engine version starting in late 2011. In 1998, CFMI launched the "Tech56" development and demonstration program to create an engine for the new single-aisle aircraft that were expected to be built by Airbus and Boeing. GE-SNECMA. [6], GE applied for the export license in 1972 as their primary contribution to the 10-ton engine project. In 1998, CFMI launched the "Tech56" development and demonstration program to create an engine for the new single-aisle aircraft that were expected to be built by Airbus and Boeing. By January 2010, the CFM56 had flown more than 470 million cumulative hours (the equivalent of more than 53,000 years).