PW remplacement de la série PW100

Pratt & Whitney Canada has launched an all-new turboprop engine for regional aircraft to replace the 1,800- to 5,000-shp PW100 series. It expects to run the core demonstrator in the second half of next year.

P&WC president John Saabas said the new engine will be “at least” 10 percent more fuel efficient than the PW100 series, which he claims is “still the most economical turboprop in its class.” There is, however, a demand for a “double-digit” fuel burn improvement, which can be met, he said, by using technology developed for the company’s latest small turbofans, in particular the new PW1000G geared turbofan powering the Mitsubishi MRJ and Bombardier C Series regional jets.


The company said it has completed the advanced study phase and is ready to launch the demonstrator program. It has “still to decide” on a date for service entry, however, and remains vague as to the likely applications. “What we do know is that there will always be a demand for fuel-efficient turboprops in the high-utilization class working 400- to 500-nautical-mile sectors,” Saabas said. “It is the best engine for the job and there are many players out there.” The current Bombardier Dash 8-400 and ATR 42/72 continue to be developed and new designs are in the cards for emerging markets in China and India, he said.

The first engine in the PW100 series–the 1,787-shp PW120–entered service in 1984, powering the ATR 42. Today’s PW150A powering the Bombardier Q400 produces 5,071 shp. Versions of the engine power aircraft in service with 365 operators in 124 countries; more than 6,000 have been produced and have accumulated more than 100 million flying hours.

The powerplant resulting from the demonstrator engine will be allied to new propeller technology under development by Pratt & Whitney Canada’s fellow company in the United Technologies group, Hamilton Sundstrand. Saabas said the new engine will not be aimed at increasing the cruising speed of regional turboprops, typically 360 knots. “In this sector, our customers are more interested in fuel economy,” he said. “We will leverage our more than 200 million hours of turboprop experience to develop the most advanced engine for this important market segment.”

Details of the turbo-mechanical features of the new engine are not being released. Saabas said only that the “best technology available” would be used to reduce weight and increase pressure ratio and, hence, core efficiency. The PW118-127 models featured two-spool, two-stage centrifugal high-pressure compressors, the more powerful PW150 moving to a three-stage axial design. Both had single-stage low and high-pressure turbines.

The new engine will benefit, said Saabas, from the same three-dimensional airflow visualization technology used for development of the PW1000G and other new turbofans. The emphasis will also be on reducing ownership costs through increased component lifetime and longer maintenance intervals. Saabas pointed out, however, that it would be “difficult” to improve on the reliability of the PW100, currently claimed to be 99.97 percent.

The first raw materials for Pratt & Whitney Canada’s new regional turboprop demonstrator have begun to arrive at the company’s Longueuil plant in Quebec as technicians prepare to assemble the compression system for the NGRT (next-generation regional turboprop). In an interview with AIN ahead of this week’s Paris Air Show, PWC vice president of marketing Richard Dussault revealed that the company has completed the design architecture and launched the demonstrator program, scheduled to culminate with a finished product some time next year.


“We’ve released the drawings and are in the process of machining the first components,” said Dussault, who noted that the company would initially test the parts individually this summer as part of a schedule that calls for running of the compressor system by the end of this year or early next year. “We now believe that we have all the ingredients to bring an engine to market that will be successful as the PW100 has been and as the PW150 is,” said Dussault.

Foremost among those ingredients ranks PWC’s Talon low-NOx combustor technology used for years in its big turbofans and a central feature of the PurePower series of geared turbofan engines now under development for the narrowbody market. While the Talon combustor cuts NOx emissions in half, according to the company, overall greenhouse gas emissions will decline at least in proportion to the 20-percent fuel burn improvement on which airlines insist for a new turboprop such as the NGRT.

“Secondly, [the airlines] generally want larger aircraft,” said Dussault. “That’s obviously not under our control. The airframers have got to decide the size of airplane they want. But I would generally say that you’re probably going to see development of 70-plus-seat aircraft into the future and we definitely see a need for a 90-passenger type aircraft.”

In response, PWC plans to size its new turboprop to produce anywhere between 5,000 and 7,000 shp, along with the capability to move into a range closer to 8,000 shp. Dussault wouldn’t venture to predict what might come first–a 70-seat replacement or a 90-seat turboprop, from either Bombardier or ATR. “I think it could go both ways; somebody could start with a 70-seat aircraft and then grow to 90, or equally they could start with a 90-seat aircraft,” he said. “The product technology that we have, the architecture we selected, could scale across a power range that would accommodate both.”

After the company tests the new engine’s compressor system, the job falls to its engineers to run the engine as a full gas generator–essentially the core, said Dussault. “After launch of a program with a customer, you would configure a gearbox and power turbines and so on, but I think the key for us is to run the compression system,” he added. Once it reaches that milestone, the engine maker hopes to officially launch the program and test the demonstrator core next year. Given those assumptions, it expects it could ready an engine for certification sometime in 2015 or 2016.

Once the program reaches its flight-test phase, likely in 2014, PWC plans to attach an engine to a wing-like stub built into the upper deck of the fuselage on one of Pratt & Whitney’s Boeing 747 test beds for flight testing from its new test and assembly facility at Mirabel, Quebec–also site of PW1000G GTF trials.

The design would offer an optimum range of between 200 and 600 nm, said Dussault, and target a niche that had once belonged to smaller turboprops but has become saturated with less fuel-efficient 50-seat jets. Now powering both the Bombardier Q400 and ATR 42/72, as well as China’s MA60, Pratt & Whitney Canada would hope to maintain its existing customer base to best justify the development cost, an estimate of which Dussault declined to offer.

“I think that’s obviously our goal,” he said. “The market has been good for Pratt & Whitney, and we have been able to develop a lot of products for it. At a certain point in time there were many other platforms, there were a lot of players, it was a growth market and then there was the era of the jet for the longer range, which sort of dominated for a while. But today it’s a more stable market and we generally think with the price of fuel there’s a lot of potential…Until there is an offer out there, there will be a limit to how big and how fast the market can grow.”

Regardless of the eventual size of the market, it seems clear Pratt & Whitney does not want to concede any of its current partnerships to GE, which has talked of using the core of the GE38 military turboshaft as the basis for a new turboprop to power an airplane carrying between 80 and 90 seats. GE, which owns Dowty Propellers and whose Middle River Aircraft Systems subsidiary holds a stake in Nexcelle, says it can develop and supply a complete propulsion system by 2015. Of course, Pratt & Whitney parent United Technologies also owns propeller maker Hamilton Sundstrand, which, said Dussault, would contribute to any integration effort with PWC.

Although Pratt has projected a market for some 3,000 regional turboprop engines over the next 20 years, Dussault considers the estimate conservative, he said, given the forecast assumed $90-a-barrel jet fuel. “Even today, we’ve blown through this,” he noted.

Bombardier and ATR have each talked about introducing turboprops larger than their respective Q400 and ATR 72, but neither has offered much detail recently about its plans. Officially, Bombardier continues to gauge market interest in its proposed Q400X, the launch of which Bombardier Commercial Aircraft president Gary Scott said last year likely won’t happen until “mid-decade, or a little later.” ATR, meanwhile, has recently gained certification for its 600 series, equipped with more powerful PW127M engines and new Thales avionics. Although at the 2010 Regional Airline Association convention in Milwaukee, ATR vice president of marketing Mario Formica called 2011 “an important year for a decision” on a larger turboprop, company executives have recently pointed to next year as a more likely timeframe.

http://www.ainonline.com/aviation-news/aviation-international-news/2013-01-02/critical-period-emerging-new-turboprop-developments

By January 1, Pratt & Whitney Canada hoped to have completed the first phase of a next-generation regional turboprop (NGRT) demonstration program intended to validate characteristics for a main centrifugal compressor. Meanwhile, U.S. competitor General Electric (GE) continues to look for an airframe launch “platform” for the proposed CPX38, which would benefit from its current work to develop the military GE38 turboshaft engine for the U.S. Marine Corps Sikorsky CH-53K.



While the two companies agree that power levels must depend on design
cruise speed and aircraft size, both program studies envision the use
of eight blades to address higher noise levels otherwise arising from
increased tip speeds of ever larger propellers.

“Demand in the regional-turboprop market will only increase,” according to P&WC
marketing vice president Richard Dussault, who suggests that the
majority of future regional aircraft deliveries will offer at least 70
seats. With detailed design for the new “centerline” NGRT
engine under way, the company claims strong relationships with airframe
manufacturers and the regional airlines driving future requirements. NGRT technology “could go up to 8,000 shp,” said Dussault.

The Canadian engine firm began testing compressor elements last year.
“We’re pleased to say all testing achieved our targets, according to
plan,” P&WC told AIN in early December. By the turn of the year, it expected to have completed the NGRT program’s Phase 1, which validates characteristics such as engine component efficiency and pressure ratio.

Aiming to achieve a 20-percent improvement in fuel consumption per
passenger and a 30-percent reduction in engine maintenance costs, P&WC
has test-run compressor hardware “to the full range of aerodynamic
design points.” The next phase of testing, at a partner facility in
Germany, is set to begin before April. “During this testing sequence, we
will map the full compressor, optimize the rotor match and assess other
aerodynamic characteristics [such as compressor airflow, efficiency and
pressure ratio],” said the manufacturer.

As part of its technology-insertion process, P&WC
also plans to launch the combustion rig demonstration program this year
“to validate emission, durability and temperature profile for the hot
section,” thereby gauging the level of performance it can provide.

Overall, the company has established a comprehensive testing program
for this year. “The primary goal will be to ensure our engine meets all
our targets so [that] we’re ready when an aircraft manufacturer
launches,” it said. “We are leveraging the latest technologies from UTC Hamilton Sundstrand to offer a fully integrated propulsion system.”

Production planning, typically involving up to 10 NGRT test engines and flight-tests on P&W’s Boeing 747SP, would follow identification of a launch customer.

Pratt & Whitney Canada a terminé la phase 2 des essais de ses moteurs turbopropulseurs régionaux de prochaine génération (NGRT) avec succès et est prête pour le développement de l'intégration rapide lorsqu'un avionneur en manifestera l'intérêt.

« Nous avons essentiellement concentré nos essais sur le compresseur de pointe que nous avons conçu pour le NGRT, a affirmé Frédéric Lefebvre, vice-président, Marketing, P&WC. La deuxième phase des essais est maintenant terminée; les résultats satisfont et même dépassent nos attentes. Grâce à notre technologie éprouvée, nous avons confiance que l'ensemble du développement du moteur peut commencer rapidement.

Le NGRT de P&WC est une réponse proactive aux avionneurs qui prévoient au cours des prochaines années la réalisation d'une cellule de turbopropulseur de 90 places. L'entreprise a développé un compresseur haute pression qui permettra au groupe motopropulseur de présenter une réduction de 20 % de la consommation spécifique de carburant (CSC) et une puissance allant de 4 500 à 8 000 SHP.