Pratt & Whitney Canada (P&WC) has revealed studies of a new family of light jet engines for general aviation and super light business jets, while Williams International has launched a similarly targeted small jet family on the back of the Century Aerospace Century Jet.
Announcing the initiative, P&WC president, Dave Kaplan, said: "We are working hard and studying a 1,000-2,500lb-thrust [4.4-11kN] family of engines for the general aviation market. We expect to validate our plans and make a final decision by the end of 1999". The new core, if launched, will provide the basis for a JT15 replacement as well as a turboprop replacement for P&WC's venerable and successful PT6 family.
Key targets for the engine include dramatically reduced parts count, cost of operation and acquisition "while providing the legendary reliability and dependability of Pratt & Whitney Canada engines", adds Kaplan.
The study was partly prompted by P&WC's recently increased presence at general aviation events. According to marketing vice-president John Wright, it became aware of the growing market opportunity at Oshkosh this year. Several airframe makers are involved in the study, "-and we're not just talking to the usual 'big three'," says Wright.
P&WC has narrowed the conceptual low-cost engine down to "about half a dozen types of layout" says Wright. One includes a swept, wide-chord fan, single axial and centrifugal compressor, a single-stage, low-pressure turbine and single high-pressure turbine. The baseline design has simple bearing and seal assemblies and a forced mixer exhaust.
The engine, if launched, would be developed in a short time says Kaplan. "We did the PW500 and PW300 in a 36-month programme. And as we have done a lot of preliminary work, we believe we could do better than that."
Williams International, meanwhile, has launched the FJ33 as the first member of an all-new 1,200l-1,500lb-thrust family aimed at super light business jets with gross weights between 6,000lb and 9,000lb (2,724kg and 4,086kg). Few details of the 1,200lb-thrust FJ33-1 have been revealed, but its swept fan design and low-pressure compressor show lineage from the FJ44 and FJX-2 programmes.
Williams says the engine will provide jet performance at "-operating costs lower than turboprops and equal to or lower than large piston engines". The powerplant will operate at altitudes up to 40,000ft (12,200m) and speeds of up to Mach 0.8 and be fitted with hydro mechanical, rather than digital fuel control.
Williams declines to specify when it will be certified, but the stated schedule of the Century Jet means it will be within the next two years. The company revealed that a prototype FJ33 is running and has amassed around 200h.
Source: Flight International
