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AlliedSignal plans to begin flight tests of its new generation AS900 regional and corporate jet turbofan in January 2000 following the successful start of initial runs at its Phoenix, Arizona, test site.

The first run, on 30 July, marked the start of an initial three-phase test period which will establish the engine's thermodynamic thrust limits, as well as basic performance and operability. "In phase two we will exercise the engine to full power - which will be about 7,500-8,000lb-thrust [33-35kN] thermodynamically," says AS900 programmes director of engineering Jim Kidwell.

Phase three, scheduled to be completed by the end of August, marks the start of the overall development and certification effort, which is due to include 13 engines and around 10,000h of running time. Certification is expected in the first quarter of 2001, leaving open the window of opportunity for the proposed application of the 7,000lb-thrust AS977 version on British Aerospace's yet-to-be launched RJX regional jet.

The AS907 version of the engine, rated at 6,500lb take-off thrust, has also been selected for Bombardier's Continental super mid-size business jet, scheduled to enter service in mid-2002.

Meanwhile, other applications are being sought by the company. "We are hoping to get another application by the end of the year," says commercial propulsion business development Victor Valente.

A key forthcoming test, set for around December, will evaluate the blade out retention characteristics of the fan containment system. Although certification tests of the fan blade-out condition are not due until later next year, the December test will be fully representative of the real thing, says Kidwell. Pending a successful effort late this year, one of the initial five test engines will be mounted on AlliedSignal's Boeing 720 testbed to begin airborne tests in January.

Source: Flight International