The Transportation Department plans to limit flights at J.F.K. airport, according to sources who spoke anonymously to the The New York Times in a story published this morning.

Last January, Congress lifted limits on the number of takeoffs and landings allowed at Kennedy airport. Since then, airlines have scheduled too many flights there. Airlines are scheduling about 100 flights an hour at Kennedy, and during peak demand hours, even more than that. But last summer, the airport was only able to handle about 80 takeoffs an hour, given summer storms and related delays, according to the Wall Street Journal.

The math is obvious. There will be about 20 fewer flights on average out of Kennedy, if the Transportation Department and the Federal Aviation Administration impose limits as expected.

Fewer flights mean that airlines will be able to charge more per flight. Fares are likely to rise because the other area airports are unlikely to be able to pick up more flights on their own.

But nothing is decided yet. The airlines are likely to fight any flight limits in court or by enlisting allies in Congress to pressure the federal agencies.

Here's why: Let's say that 20 flights a day are cut. If those 20 fewer flights cut the service of smaller airlines, such as Spirit and AirTran, the airlines will likely say that the system is unfair (anti-competitive) and arbitrary, especially if it appears to only apply to a single major airport. JetBlue is likely to be hurt the most, given that it flies more planes out of Kennedy than Delta, American, American Eagle, and United Airlines combined.

If the 20 fewer flights cut the service of the major airlines, such as Delta and United, those airlines might go to court. The major airlines would argue that the government is wrongfully taking the existing assets that they have invested to improve terminals. While federal agencies have a lot of leeway to do what they want with commercial airspace, they also are sensitive to political pressure and the potential hassles of judicial hearings and congressional interference.

Kennedy serves more than 80 airlines and an average of 65,000 travelers a day. Along with Newark and La Guardia airports, New York has the world's most crowded airspace, and more than a third of the country's flight delays happen there—causing delays to ripple nationwide, as was clearly explained by a recent story in New York magazine.

EARLIER Rage in the skies.