Chair Force Engineer

Sunday, April 02, 2006

Boeing vs. Airbus, Part 1: Beast Wars

The Boeing vs. Airbus debate is a common and very heated one that takes place within aviation circles. It often occurs that the rhetoric is more nationalist than technical in nature. The purpose of this recurring series of posts is to cut past the politics and look at the technical merits of the two airliner manufacturers.

Part 1: Beast Wars--A380 vs. 747
Airbus made headlines last year with the first flight of its A380 jumbo jet, which will carry over 550 passengers. Its prime competitor is seen as the Boeing 747, a type which made its first flight in 1969 and entered airline service in 1970. At first glance, it might appear that Airbus will beat Boeing in the long-range, high-capacity airliner segment. But two questions must be asked. First, is this market segment worth winning? Second, is Airbus's design really an improvement over the old 747?

When the A380 was first announced, Boeing planned to counter it with improvements to the 747: the 747X and 747-400X. These planes were dropped in early 2001, in favor of the abortive "Sonic Cruiser." When Boeing dropped the improved versions of the 747, it claimed that airlines didn't want bigger; they wanted planes that were faster over long routes with smaller numbers of passengers. When Boeing dropped the Sonic Cruiser in favor of the 7E7 (now called 787,) it decided that airlines would rather fly at slower speeds if it meant less fuel consumption and lower operating costs.

Since that time, the A380's sales have validated Boeing's market projections. The A380 has about 149 orders on the books with 50 options, a number which has remained almost flat since the 9/11 attacks. The 787 has since surpassed it in terms of projected sales. The nation's top airliner-buyer, Steven Udvar-Hazy, has publicly said that he only sees a market for 400-500 of these jets. While airlines like Emirates and Virgin have jumped on the A380 bandwagon, American carriers still haven't bought on.

Nevertheless, Boeing has hedged its bets with a new version of the 747. It was quietly studied as the 747 Advanced, and was officially named 747-8 when launched last fall. As the name implies, the new 747-8 will leverage technologies from the 787, including the high-efficiency GE-NX engines and various comfort features in the cabin. The fuselage will be moderately longer than the previous 747-400, and a new wing with single-slotted flaps and raked wingtips will round out the 747-8. However, the 747's future, at least in the near-term, seems to lie with cargo carriers instead of passenger lines.

The other question is whether Airbus's technical solution for building a bigger, better jumbo is best. The A380 is very similar in fuselage length to the 747; it fits more passengers in a full-length upper deck (instead of the short upper deck on the 747.) However, the A380 is a much heavier plane with much larger wings. Most airports will have to redesign their gates to accomodate it (as they did when the 747 first entered service.)

There's a graphic on the net (I think it was on Flight International's site) comparing the dimensions of the 747-400 and A380. To carry 32% more passengers, it requires 42% more weight, 24% more wingspan, 66% more wing area, and 12% more thrust. It would appear that Airbus could have come up with a jet that carried the same number of passengers as the 747-400, and done it with a shorter airplane with equivalent wingspan. Airbus's use of composite materials and newer, more efficient turbofans could have resulted in superior range to the 747-400. However, Airbus opted for for more passengers (a dubious trade) instead of a more efficient competitor to the 747-400.

Airbus has introduced a host of logistical problems by switching to two full decks. Because the upper deck will not be accessed by boarding gates, it means that all 550+ passengers will have to enter through the bottom deck and take the stairs if they have seats on the upper deck. It also means two sets of stewards and two separate food services. It will take even longer for passengers to board the A380 than with the 747. In America, we are already fed up with waiting at the airport; Americans will have little tolerance for the enhanced congestion that the A380 will introduce.

After giving the double-decker concept much thought, I have to say that I still prefer a single-deck design, even for massive airliners. In the past, Boeing had studied a single-deck jumbo jet (the model 763) that featured 12-abreast seating, and sleeper berths above the seats. I'd rather have seen Boeing forge ahead with the model 763 than the 747-8, although economic realities would prevent them from launching a massive, clean-sheet airplane like the model 763 at the same time they were doing the 787. The needs of the market are encouraging Boeing to forge ahead with a 737 replacement before they look at all-new jumbo jets.