Pratt & Whitney is developing an engine core demonstrator for the new Boeing 7E7 Dreamliner to validate the advanced technology in the heart of the engine, currently designated the PWEXX.

The demonstrator that is being designed and fabricated will run in 2004. It consists of a 10-stage high-pressure compressor, a new TALON (Technology for Affordable Low NOx) combustor and a two-stage high-pressure turbine.

The counter-rotating high-pressure compressor will have a 20:1 compression ratio and is based on technology developed for the PW6000 series engines. Several of the stages will have integrally bladed rotors. These are essentially one-piece compressor stages that have proved efficient and durable in service when compared with the traditional design in which the compressor blades are individually attached to each disc.


The TALON X combustor builds off experience in three generations of TALON combustors, each with increasingly improved emissions performance. The TALON X is configured to exceed all potential environmental requirements for the next two decades.

The two-stage, high-pressure turbine uses technology from the highly successful PW4090 engine used on the Boeing 777.

"We are confident about the technology building blocks for the PWEXX because they have each been proven in service," said Robert F Leduc, president of Pratt & Whitney's Commercial Engine business.

"Building a demonstrator this early in the development process lets us see them as a whole system. That is a significant advantage for detailed design of the full production configuration engine to make it fully service ready."

The PWEXX will have a thrust capability up to approximately 70,000lb (310kN) with a 10:1 bypass ratio. The Pratt & Whitney development team continues to work with Boeing engineers to refine the design concept to meet the requirements of the three planned 7E7 variants.

Source: Flight Daily News