Pratt & Whitney Canada (Booth N114) has shipped initial PW800 engines to Gulfstream for the G600, the second variant in the company’s new ultra-long range business jet family now under final assembly in Savannah, Georgia.

The first new model, the G500, also powered by the PW800, is rapidly accumulating test hours with four aircraft in the certification program, and a fifth, P1, soon to join. The initial G500, dubbed T1, completed its 100th flight in March, less than a year after first flight, and has recently been targeted at stability testing and refinements of the flight control system software. The P1 airframe, currently at Gulfstream’s Completion Operations facility, will join the program later this summer to undertake a minimum of 200 flight hours dedicated to interior tests.

Having switched to Pratt & Whitney Canada to power its new family in place of Rolls-Royce, its traditional engine provider for more than 60 years, Gulfstream has also focused closely on the performance of the PW800. The engine, which shares a common core with Pratt & Whitney’s PW1500G geared turbofan for Bombardier’s C Series airliner, has currently amassed “more than 2,000 hours of flight testing on the G500 and is doing everything we hoped it would,” says P&WC PW800 Marketing and Customer Services Director Scott McElvaine.

P&WC is developing two PW800 variants for Gulfstream: the 15,150 lbs. thrust-rated PW814GA for the G500 and the 15,680 lbs. thrust-rated PW815GA for the G600. The PW800 is the largest turbofan ever developed by P&WC and ran for the first time in April 2012. It made its debut on the company’s Boeing 747SP flying testbed in a year later and, although the bulk of testing has now shifted to the Gulfstream fleet, some testing continues on the 747SP. “There is always a bit of an overlap as we tweak software, so we haven’t completely ceased testing on the flying testbed,” says McElvaine.

Tests are also evaluating the performance of the integrated propulsion system which P&WC is providing in partnership with Oklahoma-based Nordam. The combined inlet, nacelle and thrust reverser system is the largest integrated powerplant system ever made by that company. Inlet compatibility testing was recently completed on G500 T2 at Eglin AFB, Florida, using a large blower array which generated cross- and tail winds up to 45 mph. T2 has returned to conduct flight loads validation and systems testing, says Gulfstream.

In early May Gulfstream also announced that wing-to-fuselage mating for the first G600 had been completed and that the aircraft would soon be transferred to the Flight Test Department for installation of test equipment. While the turbo-mechanical hardware for the G500 and 600 engines is the same, P&WC says, “we haven’t ruled out at this point some mechanical differences (in the installation). There is a significant thrust difference between them and as you get into service there might be evolution. That will start as the G600 begins to fly,” says McElvaine who explains that any minor differences will likely be restricted to the location of external tubes, wiring and brackets.”