TESTING OF composite parts of a new-technology engine nacelle for Pratt & Whitney's advanced ducted propulsor (ADP) has begun under the US Advanced Research Project Agency's affordable composites for propulsion (ACP) programme.
All the composite sections will be assembled around P&W's ADP core for full engine testing in 1997. The PW2000-based core will be geared to a 2.5m-diameter ducted fan and enclosed within a 2.8m-diameter nacelle to generate around 205kN (46,000lb) of thrust. The advanced structures used in the nacelle will be "scaleable" to enable them to be used for a full range of ADPs covering the 90-445kN range.
The P&W-led team includes Boeing, which is developing a new pylon design; DuPont, which is working on a composite fan-blade containment case; and Dow-UT, which is using resin-transfer moulding techniques to make a fan-exit case. Lockheed Martin is developing a composite core-cowl.
Large fan-cowl doors are being made by Northrop Grumman's Vought Aircraft subsidiary in Dallas, Texas, under a $22 million contract awarded by P&W in May 1994. "These are currently open to a lot of FOD [foreign-object damage]...We're trying to reduce the level of nuisance damage by having an improved damage-resistant door," says Northrop Grumman ACP programme manager Tom Beatty.
The first full-scale composite fan cowl door demonstration panels will be completed in December, with a final design to be selected by April 1996. Northrop Grumman plans to ship the first production articles to P&W in January 1997. The company's role in the ACP programme may expand to include fabrication of a composite inlet.
The ACP programme is a major element of ARPA's Technology Reinvestment Project, which seeks to preserve the industrial base by transferring technologies being developed for US national defence to commercial applications.
Source: Flight International
