GE Aviation

--EVENDALE, OHIO -- Development of GE Aircraft Engines' GE90-115B derivative engine, selected by the Boeing Company for all longer-range 777-200X and -300X aircraft, is on track to support an entry into service in late 2003. For two years, GE has been maturing the engine's design features to ensure a timely, low-risk development program. Detailed design work begins next year on the GE90-115B, which is derived from the successful GE90 engine family and will have the highest engine thrust in aviation history. The three leading features in the maturation program are:

• Nine-stage compressor. The GE90-115B compressor will be largely common to the high-efficiency, three-dimensional aerodynamic (3-D aero) compressor developed for the GE90-94B engine on schedule for certification this spring. The GE90-94B, rated at 94,000 pounds of thrust, is completing certification testing and is scheduled to power 777-200ER aircraft later this year. For the -115B, the compressor's final stage will be removed to provide greater air flow.

  This month, core engine rig tests are under way in Evendale on a GE90 scaled core with a nine-stage compressor configuration to establish operability and performance data - thus providing further development maturation prior to design of the -115B compressor.

• Swept fan composite blade. The -115B derivative composite fan grows five inches, to 128 inches in diameter, with larger-scale blades. These new dimensions, established after considerable testing and analysis, are achieved by using the same resin and carbon fiber system and manufacturing processes as earlier model GE90 fan blades. This spring, GE will run tests of scaled fan blades with a swept, high-flow design at Boeing in Seattle to better determine performance, operability, and acoustic benefits.
• Fan mid-shaft material. The fan mid-shaft, made of a steel alloy, handles the higher torque through the center of the GE90-115B with the same shaft diameter.

Additional GE90-115B features being matured by mid-year include high pressure 3-D aero airfoils and low pressure turbine low-solidity airfoils."The beauty of the GE90-115B program is its derivative nature, enhanced with key features,"said Chaker Chahrour, general manager of GE90 engine programs. "In addition, all of these new features will be fully matured before full-scale design work begins. That is the right formula for a low-risk, derivative growth engine program."