That's Not Something You See Every Day...

July 19, 2004

7B is so reliable powering the Boeing 737 that, statistically, a pilot will experience an in-flight shutdown only once every 165 years.

How can this be? The engine's current in-flight shutdown rate is 0.002, compiled from the more than 3,000 CFM56-7B engine in service. That translates to one in-flight shutdown every 500,000 flight hours. Based on a typical 737 utilization of about 3,000 hours of operation annually, that equates to one in-flight shutdown event every 165 years.

CFM56-7B engines are produced by CFM International, a 50/50 joint company between Snecma Moteurs (Safran Group) and General Electric Company.

The CFM56-7B brings the industry's most advanced technology to 737, giving customers dramatically lower operating costs while maintaining industry-leading performance, reliability, and operability.

More than 1,500 airplanes have been delivered to date, and the fleet has accumulated nearly 30 million flight hours. The aircraft's 99.97 percent dispatch reliability rate translates to fewer than one departure per 3,000 flights being delayed 15 minutes or more or canceled. In addition, the engine has an in-flight shutdown rate of 0.002, translating to one in-flight shutdown every 500,000-flight hours

The CFM56-7-powered 737 made history in 1999 when it became the first single-aisle aircraft in its class to be granted 180-minute Extended-Range, Twin-Engine Operations (ETOPS) approval by the U.S. Federal Aviation Administration, merely two years after entry into service.

The CFM56-7 includes three-dimensional aerodynamic (3-D aero) design, a high efficiency wide-chord fan, advanced electronic engine control and active clearance control systems. The engine's specific fuel consumption (SFC) is about 8 percent lower than that of the CFM56-3 on Classic 737s, resulting in better aircraft fuel burn. A reduction of 1 percent in fuel burn can mean an annual savings of up to $15,000 per aircraft. In addition, CFM has improved the engine cycle, resulting in increased EGT (exhaust gas temperature) margin, and has incorporated advanced materials and thermal barrier coatings in the high-pressure turbine for enhanced durability.

An overview of the CFM56-7 technology features follows:

FAN: The fan, designed with 3-D aero analysis techniques, incorporates 22 solid titanium, wide-chord blades and features a 61-inch-diameter fan for maximum specific flow. The resulting 92 percent adiabatic efficiency makes the -7 the best in the industry. The fan also includes a conelliptical spinner which centrifuges hail, water, and debris, thus minimizing the potential for foreign object damage to the core.

BOOSTER: The three-stage CFM56-3 booster has been improved with 3-D aero design tools for the CFM56-7, to increase airflow and enhance efficiency, thereby contributing to the engine's higher EGT margin.

CORE: The CFM56-7 shares a common core with the CFM56-5B engine powering the Airbus A320 family. The 9-stage high-pressure compressor has proven its reliability and durability on other CFM56 engine models, and it has been further improved with 3-D aero for better efficiency and aerodynamics. The high-pressure turbine also incorporates 3-D aero, active clearance control, and single-crystal N5 material in both the blades and the nozzles for improved durability, lower maintenance costs, and longer on-wing life.

LOW-PRESSURE TURBINE: The high-efficiency low-pressure turbine is also common with the CFM56-5B and features 3-D airfoils, a new case and shrouds, and improved materials.

The CFM56-7 is rated from 18,500 to 27,300 pounds (82 to 121 kN) thrust for the Boeing 737-600/-700/-800/-900 series commercial aircraft.

Jamie Jewell

+1 513.885.2282

Charles Soret

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Perry Bradley

+1 513 375 2597

Talal Ahmed Almahmood

+973 173 3819