Airbus unveils single-aisle strategy

As Airbus investigates potential future technologies that could be introduced in the second half of the next decade, Ian Goold reports that the company is considering a fourth engine option for the A320 series and continuing to improve and develop the successful single-aisle family.

1st Jun 2010

European manufacturer Airbus fired the first round in the competition to develop the next generation of 150-passenger jetliners in May, as senior executives unveiled its single-aisle product strategy for the next 20 years.

Plans begin with continued improvement of the established A320 series, including the possible introduction of a fourth engine option, and are expected to culminate in an all-new design that will embrace many innovative aerospace technologies. By the end of the next decade, a product-development study dubbed A30X could yield new designs that Airbus describes as “game-changing solutions”.

Officials say that the original business case for the A320 saw a market for about 800 aircraft, although conservative European governments asked to support the programme assumed only half that number might be sold. Today, almost 30 years on, some 4,250 have been delivered to more than 220 customers and are being flown by 243 operators. The 50-millionth take-off by an A320-series aircraft is expected before the end of June.

Airbus Chief Operating Officer Customers John Leahy points out that a new airliner will have a 40-year life and thus must represent the state of the art at entry into service. Accordingly, future single-aisle designs must sport the latest aerospace technologies, but the bad news for airlines seeking a great leap forward is that Airbus does not see an appropriate package of materials, systems, and equipment being available for at least 15 years.

"A new aircraft today would probably be metal, but we don't know enough about all-composites structures," says Leahy. "Why would you 'go' now, if you could launch an all-new composite design in [say] 2025?"

The engine situation is similar. Manufacturers say the best future propulsion probably will "be an open-rotor (OR) fan, but they haven't fully figured it out. [That will take until] the middle (or even the end) of the next decade – not before," according to Leahy.

Engine option

Meanwhile, Airbus has launched a product-development study that could see a new, fourth engine option for the A320 series being provided later this year. Such a variant would inevitably be offered as a compromise: while engine manufacturers argue that better, second-generation technology is just around the corner (and worth waiting for), some prospective customers might become impatient if fuel prices keep rising. Leahy hopes to reveal more at the Farnborough Air Show in July, with a decision following within months.

As Airbus considers this A320 New Engine Option (NEO) project, it wants to be sure that engines such as the Pratt & Whitney (P&W) geared turbofan (GTF) will provide an acceptable performance gain compared with existing powerplants.

Programmes and customer-support executive vice-president Tom Williams says the manufacturer is weighing up such issues as the impact of GTF technology on engine maintenance costs, especially for operators requiring quick turnarounds. Airbus also wants to clarify such technical questions as what the effect on the gearbox of, for instance, contaminated oil would be.

Until these queries are resolved, introduction of the GTF as an option is "not yet a done deal", says Williams.

Leahy says that over 800nm average sectors (with fuel prices increasing by 1.9 percent per year, and with a 15-year discount rate of 10 percent), the NEO offers a potential saving of US$5-9 million per year in operating costs, when fuel prices are US$84-150 a barrel.

Before going ahead with the A320NEO, the manufacturer must confirm there is real demand: "We shouldn't do it, if [it] depends on [winning] launch orders," says Leahy. He would like "Rolls-Royce and P&W [to] resolve their differences" and to proceed with a powerplant from their International Aero Engines (IAE) joint venture. Marketing vice-president Andrew Shankland believes "some improvement [is] in the offing" for the IAE V2500, while Williams confirms Airbus has been in discussions with P&W and CFM international.

Boeing response

Should Airbus decide to offer the A320NEO later in 2010, Boeing will probably announce an "all-new" narrowbody for service entry in 2020, Leahy suggests. "Do you think if we don't do anything, then Boeing will?" the Airbus executive asks, rhetorically.

Such a move by the US competitor would be preceded by its offering a new engine option for the 737 in 2011, predicts Leahy. Were Boeing to launch a new 150-seater to replace the 737 in, say, 2018-20, Leahy claims it would need to sell an additional 1,000-2,000 units after fulfilling its current 2,000-strong backlog of orders (assuming a 24-month linear run-down in production ahead of a replacement).

But he also remembers Boeing's history of promoting (and then dropping) new designs in response to Airbus initiatives. After Airbus launched the A320, Boeing offered the 7J7 in 1985, but postponed it six months after the A320 flew in 1987 (and six years later introduced the 737NG). Leahy says Boeing came up with the Sonic Cruiser within 90 days of Airbus's late-2000 launch of the double-deck A380, before replacing the high-speed, canard design with the conventionally configured 787 in 2003.

As Airbus mulls the possible A320NEO project, production of current variants remains "full steam ahead" and development of further improvements continues. Williams is "pretty confident" that monthly manufacturing rates will increase to 36 in December.

He reports that some customers are “looking for early delivery”, while Airbus is “comfortable” with its current backlog of 2,200-plus orders. Leahy says A320s have retained their market value "very well", with examples "quickly returning to service after coming off lease".

New ‘sharklets’

One upcoming A320 improvement is next year's planned introduction of upturned wingtips (dubbed "sharklets") that are claimed to improve fuel-burn per seat by up to 3.5 percent on longer flights. The sharklets will offer a range increase of up to 100 nautical miles, around 1,100lb extra payload, or up to 6,600lb additional take-off weight.

Three other enhancements are also in the wings: a cargo conversion (being developed by EADS-EFW with Russian partner Irkut), a fuel-tank inerting system (FTIS), and extended service “life”. Williams confirms that there has been a delay in expected demand for A320 passenger-to-freight (P2F) modifications, but expects “very strong” interest by 2012-2013, especially from Asia and from India in particular.

Airbus reckons that there are “a lot of old [Boeing] 727 freighters to be replaced, [with] a lot of [A320s] available”. According to Shankland, the A320 P2F will sport a reinforced cargo floor, a 121 x 86 inch side-loading main-deck door, and a barrier wall between courier accommodation and the cargo compartment. Testing of a conversion mock-up is under way.

This year should see delivery of 11 A320s equipped with the new FTIS, says Airbus. By May, the first system had been fitted on a new production aircraft and a service-entry date agreed with customers.

Airbus has been completing – ahead of schedule – fatigue tests related to a further extension in A320 service life, says Williams. Simulated operations have achieved “between 138,000 flight cycles (FC) and 170,000 flight hours (FH)”. Allowing for safety margins, the manufacturer is aiming to offer ultimate A320 inspection intervals of 90,000 FC/180,000 FH, via an interim extension to 60,000 FC/120,000 FH.

Further improvements promulgated for the Airbus single-aisle series include a continuous review of potential weight savings, the redesign of 40 computers and systems and new cabin-interior enhancements, including improved overhead luggage bins, wall and ceiling panels, lavatory, galley and added capacity for up to eight extra passenger seats.

Long-term value

Leahy reports Airbus is investing 100 million euros per year “to enhance the [A320's] long-term value”. He sees “great opportunities” for the A321 to take the place of the discontinued Boeing 757-200. The A321 is said to fly 120 nautical miles further (allowing “true transcontinental” Boston-San Francisco flights), or offer 3,300lb higher take-off weight for (Maui (Hawaii)-San Francisco services).

In a two-class configuration over 2,000 nautical mile legs, a 185-passenger A321 equipped with "sharklets" is estimated to burn 17 percent less fuel per seat than a 192-seat 757-200. Leahy says that, by comparison, a 173-seat 737-900ER with winglets would offer a benefit of just 7 percent over the 757-200.

Ian Dawkins, Airbus’s senior vice-president for strategy and future-programmes, says the long-standing Airbus/Boeing single-aisle duopoly will end as new mainline-market competition emerges from Canada's Bombardier and manufacturers in China and Russia. This development has encouraged the European manufacturer to consider “long-term, game-changing technologies to take forward [Airbus products, including] new configurations and how to integrate them beyond 2025”.

He says an Airbus exercise dubbed "A30X" is looking closely at the necessary characteristics for a future single-aisle aircraft programme. “The requirements will drive technology and decisions” on the programme, he says.

Potential technologies that could play a part include bio-fuels, fuel cells, innovative structures, and ‘smart’ wings, as well as new cockpits and air-traffic management systems.

Dawkins argues that the Bombardier C Series, Comac C919, and United Aircraft MS-21 projects – all planned for service entry in the coming decade – do not offer a technological “step change”. Leahy regards Bombardier as "the only credible [competitor].

Canadian ‘threat’

“There is no need for Sukhoi and the others because the A320 and [Boeing] 737 are established in the marketplace," he says. For Williams, Bombardier is "a threat" and he assumes that there "will be [at least] a Chinese single-aisle [design]".

A new aircraft employing geared OR engines for service entry in 2025 or later might offer a 35-40 percent improvement in fuel-burn per seat (or 20-25 percent better cash cost per seat), compared with current machines, says Leahy. He echoes his suggestion that an A320NEO could well spark a knee-jerk reaction from Boeing, when suggesting that only about half this improvement could come on a new 2020 design without such engines.

Finally, Dawkins foresees engines with new OR architecture offering a “quantum leap” in reducing specific fuel consumption. He concludes that the challenge with advanced turbofans will be to accommodate large fan diameters, integrating “an A330-size engine on an A320-size airframe”.

Asian Aviation at a glance