To those unfamiliar with the precision and complexity of the engines that propel an airplane into the sky, the innovation that is turning a new Pratt & Whitney engine into the power plant of choice for airlines appears deceptively simple.
It's just a gearbox, installed between the engine's fan blades and turbine. But it took more than a decade of research and an investment of at least $1-billion (U.S.) to come up with a breakthrough that is transforming the aircraft industry.
The solution is elegant. Fans are most efficient when they are turning slowly, turbines when moving faster. On existing airplane engines, designers compromise, so one revolution of the fan means one turn of the turbine.
But on the new Pratt & Whitney engine, for every revolution of the fan, the turbine will turn three times. That means less noise, lower emissions and, most importantly, a cut in fuel consumption of about 15 per cent compared with existing engines.
For the handful of companies that dominate global airplane making, the Pratt & Whitney PurePower geared turbofan engine is a crucial advance, and one they are highlighting as they negotiate with airlines desperate to reduce fuel consumption amid soaring prices for jet fuel.
For Bombardier Inc., the engine is a particularly important selling point on its new C Series aircraft. Industry observers expect the company to announce new orders for the jet at the Paris Air Show next week.
The promise of the new engine was a key factor in the company's decision to revive the C series project in 2008, two years after it shelved the program.
The C Series, which is scheduled to make its first flight next year, represents one of the most ambitious engineering and manufacturing projects in Canadian history, and catapults Bombardier into the large commercial airplane market, a territory now dominated by Airbus SAS and Boeing Co.
Airbus has responded to the Bombardier move by offering new engines on its the A320 family of airplanes, which are the France-based aviation giant's best-selling planes. It also expects to unveil new orders at the Paris show.
Airbus has secured 120 firm orders and among those airlines that have chosen engines, all have picked the Pratt & Whitney model over the Leap-X being developed by CFM International, a consortium of General Electric Co. and the Snecma division of France-based Safran Group.
Soaring fuel costs and increasingly restrictive noise ordinances have made state-of-the-art engines all but compulsory for airlines. Fuel costs have jumped by as much as 30 per cent this year. The financial penalties stemming from older engines will rise even more next year, when European airlines will be required to participate in the European Union's carbon emissions trading scheme.
The PurePower engine will be the first of a new generation of engines to arrive in the narrow-bodied airplane segment, where the Airbus-Boeing duopoly is under assault as never before with the C Series and new planes under development by Chinese and Russian manufacturers and possibly Embraer SA of Brazil.
While the airplane makers duke it out for supremacy in the narrow-bodied market, so are engine manufacturers, promising new technologies that will save millions of litres of fuel. At stake is an engine market worth an estimated $120-billion (U.S.) over the next 10 years as the new narrow-bodied planes arrive.
Now, other airplane makers and airlines are waiting for Boeing's reaction as it ponders whether to match Airbus and offer new engines on its 737 in the middle of this decade, or wait until it can design and develop a completely new airplane by 2019 or 2020.
Some airlines are getting impatient. Even Southwest Airlines Co., one of the most loyal Boeing customers with almost 600 of the Chicago-based airplane maker's 737s criss-crossing U.S. skies, is making loud noises about needing more fuel-efficient planes - and soon.
"Ultimately if the airlines don't go bankrupt, the higher the fuel prices the more they realize they need to have the most modern, most fuel-efficient aircraft available," John Leahy, Airbus chief operating officer of customers, told consulting firm AirInsight.
For airplane makers, the narrow-bodied jet market is the biggest market, worth some $1.4-trillion over the next 19 years.
Because these planes are the workhorses of the industry, airlines want what they call "game changing" technology that will be more efficient, more environmentally friendly and quieter.
"That's bread and butter right there. That's a real big chunk of the market," says Will Alibrandi, aero gas turbine analyst at aviation consulting firm Forecast International Inc. in Newtown, Conn., who provided the estimate that the engine market alone is worth $120-billion.
Pratt & Whitney has drawn first blood in the battle for Airbus customers, jumping back into a market it dominated decades ago when one of its engines was the only choice for buyers of Boeing 737s.
A rush by airlines to order A320 models equipped with the new engine has prompted Airbus to advance production of its A320 New Engine Option by six months so airlines can begin flying the planes by October, 2015, instead of the second quarter of 2016.
The Airbus win was important for several reasons, Pratt & Whitney president David Hess told investors on a conference call earlier this year.
"This one is going to enable us to take back share in the larger commercial engine business," Mr. Hess said, "specifically in the near term in the most lucrative segment, the narrow-body segment.
Pratt & Whiney, a unit of United Technologies Inc., UTX-N has raced ahead in part because of a head start in demonstrating the engine. It tested it first on its own 747 and then for 100 hours on an Airbus A340.
"The bottom line here is that Pratt is closer to substantiating their fuel efficiency claim than GE/Snecma," says Bill Storey, president of Teal Group Corp., an aerospace consulting firm based in Fairfax, Va.
The timing of the Pratt & Whitney engine becoming available on the C Series by 2013, along with advanced composites for the wings and an aluminum lithium alloy for the fuselage, was critical in Bombardier's decision to revive its project, says Robert Dewar, C series vice-president. Mr. Dewar was one of about 50 people who kept working on the program after Bombardier shelved it in 2006.
The company wanted to be sure, however, that the Pratt & Whitney engine represented the breakthrough that Bombardier and its airline customers expected. So it set engaged a team of about 10 industry experts from outside the company, most of whom were from within the industry but had retired.
"What was clear to us was that Pratt with the [geared turbofan]ndash;at that time it wasn't even named-had a clear advantage to the competitors in terms of what they were offering [and]what time they could offer it," he recalls.
An early version of the Leap-X will power the C919, the Chinese entry in the narrow-bodied sweepstakes that is targeted to arrive a year later, but the first engines won't have all the advances that will be available by the time Airbus offers them in 2015, Mr. Storey pointed out.
As would be expected, Pratt & Whitney is trumpeting the advances it has made.
"An engine manufacturer has never delivered-in a one-step new product-double-digit improvement in fuel consumption," said Bob Saia, who began working on the program in 1998 and is now vice-president, next generation product family.
The benefits from that gearbox multiply in several ways, Mr. Saia said.
Because the fan can turn more slowly, it needs fewer blades - just 18, compared with 22 to 24 in a conventional engine. But the fan is bigger, so the blades are wider and move more air. A slower fan also means a quieter engine.
Also, a turbine turning at a higher speed can be a lot shorter and a lot lighter. A lighter turbine means the entire engine weighs less.
"Then there's a ripple effect in terms of how you install it on the airplane," Mr. Saia noted. "It actually gets installed closer to the wing, so then you start to save aircraft weight."
Fewer parts means lower maintenance costs and longer intervals between overalls, saving airlines money in other ways.
The Leap-X does not make use of a gearbox, but fan blades made of composites that weigh less than those made of steel. Another material called ceramic matrix composite, which also is lighter in weight, can withstand the higher temperatures generated inside a jet engine.
CFM says its engine will provide fuel savings similar to those generated by the Pratt & Whitney engine.