Improved turbofan launched to power new PiperJet sport utility aircraft will offer improved fuel economy

Williams International has revealed more details of its recently announced FJ44-3AP turbofan following its launch by Piper for its new sport utility PiperJet.

Based on the 3,000lb-thrust class (13kN) FJ33A powering the Cessna Citation CJ3 and Grob SPn, and derated to 2,400lb for the PiperJet, the new version is expected to offer a 4% improvement in fuel economy over the baseline engine, says Williams business development vice-president Matt Huff.

The improvements in the -3AP are associated with three-dimensional aerodynamic enhancements throughout the flow path, that were originally tested as part of development work for the larger FJ44-4A. This engine, in turn, is being developed for Cessna's recently launched Citation CJ4 and will provide 3,400lb of thrust, compared with 1,280kg from the CJ3's FJ44-3A.

"We've done a lot of rig testing and verifying the aerodynamic improvements for the -4A in the -3A size. This did two things: it proved out the aerodynamic changes sooner and, of course, we ended up with an improved -3," says Huff. Williams does not, however, expect existing -3A users to switch over immediately to the newer version when it becomes available for the PiperJet.

"We're not trying to steer any of them to it yet. They will decide on the upgrade when and if it is good for business, or for other marketing reasons," says Huff. "We don't expect anyone would need it for more thrust, but all would benefit from more range."

The -3AP is expected to be certificated in the first half of 2008, supporting Piper's plans for the start of PiperJet tests later that year. Initial deliveries of the all-metal, six-seat aircraft, with an option for a seventh seat or enclosed lavatory, are planned for 2010.

The PiperJet will be certificated for single-pilot operations with a 360kt (665km/h) cruise speed, 35,000ft (10,700m) ceiling and 2,400km (1,300nm) range.

The development of the -4A is following a similar schedule. First flight of the CJ4 is set for the first half of 2008 and entry into service for the first half of 2010.

Williams also expects to ship a further pair of FJ33s to Spectrum Aeronautical by mid-year for the planned resumption of flight tests of the Spectrum Freedom (formerly the Spectrum 33) around September. Williams will provide the powerplant for the all-composite Freedom jet, while GE Honda is providing its larger HF120 for the Spectrum 40 Independence, a larger nine-passenger jet.




Source: Flight International