Expectations that fuel costs will continue to smart, coupled with regulatory pressure to reduce emissions, has made it even more critical for engine manufacturers to design a new powerplant that ensures the next-generation of narrowbodies offer a “quantum leap” in efficiency, says American Airlines, which is eyeing a replacement for its 425-strong fleet of Boeing MD-80s and 757-200s.

American Airlines executive VP of operations Bob Reding, who is responsible for the carrier’s maintenance and engineering, flight, and domestic airports organization, tells ATI that it has become “more and more important and critical that we have an efficient engine not only from a fuel consumption perspective but also our emissions” – both CO2 and oxides of nitrogen emissions.

The Oneworld alliance member in recent years has taken a number of steps to reduce fuel consumption and emissions, including adding winglets to its 757s and new tail cones to the MD-80s. It has been a “cross-dimensional, cross-departmental” effort involving the pilots, mechanics, dispatchers and others, says Reding. “We have done as much as we can internally for fuel conservation to lower our fuel costs and to lower harmful by-product for burning fuel.”

However, as the carrier looks forward to the future, it is “very, very interested in talking with all the engine manufacturers” to “push forward with new engine technologies as well as improve the current engines”, says Reding.

Original equipment manufacturers (OEMs) are hard at work on new-engine technology. Among these efforts, CFM International partners General Electric and Snecma are developing technology for both an advanced turbofan and an open-rotor engine, with a choice between those two architectures planned before the decade’s end. A 2018 entry into service is considered feasible. The open-rotor concept is also being pursued by Rolls-Royce.

This technology, and the promise that this could give a 25% to 30% improvement in efficiency, “seems to be really a paradigm shift in fuel consumption”, says the American executive VP.

He notes, however, that questions still need to be answered concerning the maximum cruise speed that aircraft can fly with open rotors, the noise characteristics and certification requirements.

“There will probably be some blade-out requirements,” says Reding, adding that since certification requirements are not yet written “that is certainly one of the unknowns and certainly one of the issues that will have to be addressed”.

American is “very supportive” of new technology efforts, including the Pratt & Whitney geared turbofan (GTF) that has been selected by Bombardier for its proposed 110/130-seat CSeries airliner and by Japan’s Mitsubishi for the Mitsubishi Regional Jet (both with 2013 entry-into-service dates). However, the carrier is really looking for a next generation narrowbody that will have an average of 150 seats.

American operates about 300 MD-80s and 125 757s. Replacing these aircraft and acquiring new-design narrowbodies for which to grow the fleet is of paramount importance. “We could operate 130 seats in several of our markets but we look at what we really need that makes the most sense for us and it’s really the 150-seat aircraft,” says Reding.

“It doesn’t mean if we had an absolutely wonderful airplane with 140 seats that we wouldn’t take a close look at that. But we are asking the OEMs to really take a close look at 150 seats. Our 757s have 187 seats. Since our 757s fall into that potential replacement as well, we need an airplane that could really replace our 757s [as well].”

While American would like to see the next generation aircraft enter the marketplace “sooner rather than later”, it hasn’t yet disclosed an exact timeline.

To support near-term growth, American has been adding Boeing 737-800s. The carrier also has outstanding options to add more -800s to the fleet. These airframes “can provide some interim replacement for our MD-80s as we really pursue hopefully finding the next breakthrough technology for an engine that provides substantial benefits”, says Reding. “We’re looking at an engine that can beat that from 12% to 30% but clearly 30% would really get our attention.”

Widebody replacement, while important, “is not as urgent”, says Reding, since American has just undergone major refurbishment of most of its widebody fleet.

Eventually, however, the carrier “will have to look at what airplane makes sense for us to replace the 767, which is no longer being manufactured by Boeing, [and] what will replace our [Airbus] A300-600s”. Of continued interest to American are the Airbus A350 and Boeing 787. “We think the A380 at this point in time is a little to large for the kind of service we operate for high-frequency business travellers. The A380 is probably not being studied as intensively as the A350 and 787,” says Reding.

Source: flighglobal.com's sister premium news site Air Transport Intelligence news

Source: FlightGlobal.com