"Part of our plan to be successful in New York requires us to be in London with lots of frequency," says Continental’s Compton. "London is crucial to our worldwide network, and you can't do a market like London without [a lot of] flights."

Grimmett of Delta also points to London's transatlantic primacy as the reason her carrier has hung in with its two daily flights from its large Kennedy hub. "There's a halo effect from New York-London service," she says. "As you work through your corporate contracts, having New York-Heathrow makes you better able to compete for all of a company's business. If we could fly more to Heathrow, we would. We're always looking to acquire [takeoff and landing] slots at Heathrow."

For his part, Rossi at Virgin Atlantic thinks the NyLon market "bottomed out last July and August. We're seeing an upturn. It's not off to the races, but it's better than it was."

In the long run, the question airlines have about NyLon remains their ability to once again charge bankers and other travelers a premium in the premium classes. Full-fare walk-up prices in business class between New York and London are often double the posted fare for flights to other European destinations. But because there are still so many seats available between New York and London, discounting is rampant, especially in the premium classes.

Jonathan Weiner, a senior vice president at British Airways' Americas division, admits NyLon "has a long way to go to get back where we were two years ago." In fact, BA's yield in its premium-class cabins was down 10 percent in the last 12 months, nothing to sneeze at when you consider this statistic: Just in U.S.-generated sales, BA produces more than 50 million pounds of revenue annually from travelers sitting in its business-class cabin between New York and Heathrow. And that number only includes flyers beginning their travel at Kennedy Airport and ending it in Heathrow, the so-called O&D (origin and destination) traffic that is a subset of BA's total market on the route.

"We could be looking at a permanent reset in [NyLon] pricing," says Carter of American. "It's just too early in the recovery to tell."

The Fine Print…

Another factor complicating the New York-London situation: It is the linchpin in the debate over whether British Airways and American Airlines receive antitrust immunity for its Oneworld Alliance. The carriers' competitors in the Star and SkyTeam alliances already have ATI, but British and American's efforts have already floundered twice in the last decade. The U.S. Department of Transportation last month tentatively approved a BA-AA tie-up contingent upon their surrendering several takeoff and landing slots in the New York-London market. European regulators have yet to rule.

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