"If you find the reason for the PT6's longevity, could you please let us know!" Pratt & Whitney Canada's (P&WC) ebullient young boss is as impressed as the rest of the aerospace world at the way the evergreen turboprop keeps on rolling.
He has a few ideas about what has kept the PT6 at the top of its game and selling well some 50 years after launch: "It's reliable, durable and affordable, and we've kept on improving it over the years - the PT6 of today is not the engine that first entered service in the 1950s."

Keeping essentially the same diameter, P&WC has stretched the engine several times and injected new technologies into the compressor, turbine and combustor. So effective have the succeeding developments been that the biggest PT6 is rated at close to 2,000shp (1,500kW), four times that of its Fifties grandparent. "And it's still got a lot of development life left," declares Bellemare. "We're going to carry on pushing it because people keep asking us for even more power."

Bellemare is just as optimistic about the length of time the venerable turboprop could stay in production. "Look at the PT6-powered T-6A Texan II military trainer, which entered service a couple of years ago. Military training systems tend to last many decades. Add that to the 50 years of the PT6 to date and we could have a programme that will one day approach 100 years in production."

While he's making no such claims for the 900-3,000lb (4-13kN) thrust PW600 family - chosen to power the three leading very light jet (VLJ) contenders, the Cessna Citation Mustang, Eclipse 500 and Embraer VLJ - he entertains hopes that it could eventually hit the annual production heights scaled by the PT6.


"We approached the PW600 as a high-volume enterprise from the beginning," says Bellemare. "We're gearing up for as many as 1,500 units a year. If the market responds extremely well, we'll be able to produce even more. If it doesn't, we have the flexibility to adjust."

At present he sees no realistic prospect of any further PW600 platforms in the VLJ sector, however. Perhaps that's just as well, because with its PW535E the company is also aboard another potential best-seller - the Embraer Light Jet.

"We believe in the PW535E and the Light Jet the way we believe in the PW600 and its platforms. In the LJ Embraer is bringing good value to the market, so we should also see good volumes on the PW535E."


P&WC won the Light Jet in competition with Williams International and its FJ44. The pedigree of the PW535 family as a whole was the deciding factor, Bellemare believes. "The PW535 is a proven engine with solid technology and a lot of hours powering the Cessna Citation Encore. Add in the 535E's FADEC and the acknowledged quality of our aftermarket network and you can see that we had a very attractive offering."

PW535E development is well in hand, aimed at adding more thrust and moving from hydromechanical controls to the FADEC. "It's not a brand-new engine, of course," comments Bellemare. "But every time you ask engineering to do something, it's never cheap - they always want tens of millions of dollars!"

Besides leading the VLJ field, the Canadian company also has a place in the two top box-office programmes of Paris 2005 - the Airbus A380 and the Dassault Falcon 7X. The PW980A, the largest auxiliary power unit (APU) ever specified for a commercial aircraft, is aboard the A380. And Dassault's debutant is powered by the PW307A, rated at 6,400lb for take-off.

"The current 7X backlog - it's around 50 or so aircraft already - suggests that this is going to be a very successful programme," remarks Bellemare. "The aircraft's got three engines - we always like that! And at this point PW307A performance is just flawless: we've accumulated over 4,500h in development testing and the engine was certificated ahead of the 7X first flight.So it's a programme in good shape." The other PW300-family turbofan to be spotlighted here is the PW308, powerplant for the Falcon 2000EX and the new Hawker Horizon. "We have well over four million hours on the PW300 family," Bellemare says. "We've had our challenges but now there are some very solid products out there in the marketplace."

P&WC's healthy standing in the corporate aviation market is matched by a leading position with regional turboprop manufacturers ATR and Bombardier. What does this year's resurgence in their market mean for the prospects of the PW120 and PW150 families?


"We don't believe that regional turboprops will ever recover to a point where they could start displacing regional jets," Bellemare says. "But the props do still have a place on routes around 300-400nm (550-740km) - at those distances there's nothing that beats the economics of a turboprop. As oil prices keep going up, operators will be ever more sensitive to fuel burn, and so the turboprops will continue to win business. For us it's still absolutely a game worth being in."

But Bellemare's devotion to the turboprop stops short of giving the green light for new product development. "We've always said that we could derive turboprops from the PW600 and from our new PW210 turboshaft. But first we would really need to understand the nature and size of the market, and how serious it is.

"When you already have engines like the PT6 and our other props that perform well and are affordable, reliable, durable and maintainable, you have to think twice before launching something brand-new."

Currently there's but one shadow falling across the sunlit landscape inhabited by P&WC. Despite its best efforts in a succession of competitions - the Russian Regional Jet, China's ARJ21 and the Airbus A400M military freighter - the Canadian company has yet to secure a launch platform for its PW800 10,000-20,000lb thrust turbofan.

Source: Flight Daily News