In a perfect world, several airlines would already be flying the Boeing ( BA) 787 Dreamliner.

As Delta ( DAL) CEO Ed Bastian said recently at the JPMorgan transportation conference, "We'd already have eight flying at this point in time had Boeing been able to deliver."

In reality, however, the airplane faces a two-year delivery delay, meaning it will arrive in a far different economic climate than the one that existed in mid-2008.

Boeing 787 under construction

In general, the 787 delays have resulted from Boeing's effort to establish a new production process, with a far-flung supply chain shipping components to Boeing's Everett, Wash., plant, where the sixth and final 787 flight test aircraft is currently being assembled. The airplane is powered with General Electric ( GE) GEnx engines.

For customers, it is unclear whether the economic downturn since the original delivery date lessens the negative impact of delay. Some airlines have expressed displeasure that they have to wait, but the interest of others -- such as Delta -- may have waned.

"Assuming the airplane has the performance they promise, airlines want that sucker as fast as they can get it on the ramp," says airline consultant Mike Boyd. "These are replacement airplanes, they will have lower operating costs, and you want them now."

But in a recent filing with the Securities and Exchange Commission, Delta said it had dropped the aircraft from its 10-K report on new orders. "We have excluded from the report our order for 18 B-787-8 aircraft," Delta said, because Boeing has said "it will be unable to meet the contractual delivery schedule for these aircraft." At the conference, Bastian said the two parties are still talking.

Says Aboulafia: "I guess there's a fair number of customers happy not to take it, so it could have been worse if the market were great, but that's a relatively small silver lining."

No one can say with certainty what the world economy will be like when 787 deliveries begin, now scheduled for the first quarter of 2010.

However, Scott Hamilton, publisher of an online newsletter that covers aircraft manufacturers, says: "By sheer luck, the delays have proved to be a boon to the industry because the airplane is not delivering at the depths of the downturn.

"Bear in mind that initially the delivery rate will be extremely low, he adds. "By the time it gets to where Boeing wants it to be, the global economy should be back to normal."

As for the A330, Airbus spokesman Clay McConnell says, "It is the most modern intercontinental airplane flying today, and we continue to see a great deal of interest and strong demand, even in the uncertain economic times."

Unlike the 787 and the Airbus A350, the 330 -- with seating for 250 to 300 passengers and a range of 6,800 nautical miles, is available. McConnell says delivery slots are available in the next few years, and aircraft lessors also have planes available.

Meanwhile, the sixth and final 787 flight test aircraft is now undergoing final assembly at Boeing's Everett, Wash., plant. The airplane will be powered with General Electric ( GE) GEnx engines.

"Progress continues on the fleet," Boeing said recently, in a prepared statement. The first test aircraft has been getting its paint touched up. Verification tests on the second aircraft are "progressing well." Production work on five other test aircraft continues, and 31 of the 787s are in production throughout the supply chain. Boeing says it has it has orders for 878 Dreamliners from 57 customers.

While Boeing has acknowledged that the first six airplanes are above the anticipated weight, spokeswoman Loretta Gunter notes that all six are test models. The first airplane that will provide us with a meaningful weight is Airplane 7 and we won't weigh that for some time."

Certainly, the airplane's promise of improved fuel efficiency has not gone out of style, even if oil has fallen from the high of $147 a barrel it reached in July. The 787 is 20% more fuel efficient than the comparably sized Boeing 767.

Oil was trading Tuesday around $53 a barrel.

"When this airplane was announced in December 2003, fuel was at $33 a barrel, and airlines were complaining then that they needed better efficiency," says Hamilton. "Today's price is still a lot higher than $33. So you still get the fundamental benefit."

Shares of Boeing closed up 60 cents, or 1.7%, to $36.10.

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