Guy Norris/LOS ANGELES
The General Electric-Pratt & Whitney Engine Alliance plans to begin critical core rig tests of the GP7000 engine for the Airbus Industrie A3XX and Boeing 747-400X next January.
The core rig tests were originally due to begin in the fourth quarter, but have slipped to a target "fire up" date of 21 January to allow time for newer technology to be fully integrated into the design.
Pending a successful test series and a firm A3XX launch decision by Airbus Industrie during next year, the joint venture plans to hold its crucial "toll gate six" meeting in May 2001.
This will firm up the engine configuration and form the official launch of the certification process. "From that point to certification will be 30 months, so our certification target is November 2003," says GE-P&W Engine Alliance president, Bruce Hughes.
The initial version of the engine to be certificated will be the 75,000lb (334kN) GP7275 with a 2.79m diameter (110in) wide chord fan. A 67,000lb-thrust derated version, the GP7267, is expected to be the first to enter service on the A3XX-100.
"Airbus is talking about probably doing the freighter as the next version, and that will need 75,000lb thrust," says Hughes. The higher thrust GP7275 will also power the longer range -100R and passenger -200 versions.
The first full GP7000 engine test is scheduled for July 2002, with initial flight tests beginning on GE's 747-100 in February 2003. Target entry into service dates are mid-2005 for the A3XX-100 and mid-2007 for the freighter.
Hughes says specific fuel consumption has been improved by 3% and weight reduced by 205kg (450lb) since July 1997, "with another weight reduction of about 75lb due next month", he adds.
Most of the improvements have been produced by design changes to the engine that have been possible because of the delayed A3XX development timescale. They include the introduction of swept stage-one high-pressure compressor blades and other three-dimensionally designed aerodynamic changes throughout the core.
The alliance is also studying the application of swept fan technology, and says there will be a decision by mid-way through next year.
Meanwhile, development progress on the smaller, 2.5m-diameter GP7167 engine for the proposed 747-400X is effectively on hold while Boeing continues to wait for market reaction to its wing root insert derivative.
For -400X derivatives below 1 million pounds take-off weight, the two firms will compete with the CF6 and PW4000, respectively.
Source: Flight International
