We're serving our customers; Airlines are already responsive; new law could make things worse.

Flight delays are frustrating to everyone -- passengers and airlines alike. Another law will not relieve that frustration but could have many unintended consequences.

An airline's primary responsibility is to transport customers safely and promptly. An airline that fails to meet its responsibilities risks losing those customers.

Delays, however, often are not simple or easily containable. Because of the complexity of airline operations, the effects of delays cascade through an airline's system, causing serious operational and economic harm -- providing airlines with an even stronger incentive to avoid delays.

Most delays occur because of weather or airspace issues or a combination of both, aggravated by our antiquated air traffic control system. Airlines will not fly when conditions do not ensure the highest margins of safety. But go/no-go decisions are made by pilots, airline operations professionals and the Federal Aviation Administration -- experts who have on-the-scene knowledge. No law or government mandate can substitute for the judgment and experience of such experts.

The same can be said of caring for passengers during long delays. ATA members:

*Reviewed their passenger-service commitments to ensure essential onboard services (food, water, medical and lavatory).

*Updated their operational contingency plans.

*Provided the Transportation Department's inspector general with those plans. Indeed, earlier this year, ATA urged the department to examine this matter.

*Provided Congress with their plans to provide essential services during long delays.

*Incorporated parts, if not all, of their commitments into their contracts of carriage.

These are unmistakable commitments of responsiveness and transparency. A new law will not improve on that. In fact, in an era when many flights are fully booked, a law that mandates cancellations is likely to result in greater rebooking frustration.

One area, however, demands decisive and quick congressional action: rapid modernization of our aging air traffic control system. Without that action, delays will inevitably worsen and no one wants to see that happen.

James C. May is president and CEO of the Air Transport Association, the trade group for major U.S. passenger and cargo airlines.