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CFM56-5B/P Delivers on Promise of Improved SFC

February 24, 1998

SINGAPORE - CFM International's advanced CFM56-5B/P engine is delivering on its promise of dramatically reduced fuel consumption in its eighteen months of revenue service, providing operating airlines up to a 3 percent improvement in specific fuel consumption (SFC) compared to base CFM56-5B levels.

CFM International is a 50/50 joint company of Snecma of France and General Electric of the United States.

Developed specifically for the Airbus Industrie A320 family, the CFM56-5B/P entered service with Swissair on the Airbus A319 in August 1996. The engine has since entered service on the A320 and A321, and has maintained a 99.96 percent dispatch reliability rate and has experienced no in-flight shutdowns or aborted takeoffs in operational service.

The -5B/P, which combines industry-leading CFM56 reliability with state-of-the-art technology, features a redesigned high-pressure compressor (HPC) and high- and low- pressure turbines (HPT and LPT) for improved efficiency. Three-dimensional aerodynamic analysis techniques were used to design turbine blades to reduce losses at the blade tip and root, thus improving HPT efficiency. This same 3-D technology, coupled with computational fluid dynamics, also resulted in more efficient blading in the LPT and the HPC. The 3-D airfoils significantly reduce engine cycle temperatures and, as a result, increase the exhaust gas temperature (EGT) margin. The higher EGT margin ensures appreciably more time on wing, both first run and after a shop visit, and lowers maintenance costs relative to the base -5B levels.

The CFM56-5B/P powers all members of the A320 family and is now the standard production configuration for all -5B engines. In March 1997, the 32,000-pound-thrust CFM56-5B3/P was certified on the new 89-tonne Airbus A321-200. This growth version of the aircraft gives airlines much greater range than the A321-100.

The -5B/P and its predecessor, the CFM56-5A, power the majority of Airbus A319/A320/A321 aircraft currently in service or on order. The -5A entered revenue service on the A320 in 1988 and has since logged more than 10.8 million flight hours. The engine's reliability and low cost of ownership rank among the best in the industry. In 1996, the 23,500-pound-thrust CFM56-5A5 was certified on the Airbus A319 and entered service with Air Canada in January 1997.

The CFM56-5B entered service in March 1994 and has logged nearly 700,000 flight hours (including the -5B/P) and has maintained outstanding operational reliability. The engine can be equipped with an optional double annular combustor that reduces NOx (oxides of nitrogen) emissions by 45 percent compared to engines equipped with a single annular combustor. CFM International is the only company to offer low NOx combustor technology in this thrust class.

The CFM56-5B/P core serves as the basis for the new CFM56-7 engine, as well as the proposed CFM56-9 engine for potential 100-passenger aircraft.