The airlines issued grave warnings about "unintended consequences" when the 3-hour tarmac delay limit went into effect recently in the U.S. Since then, there have been some cancellations but there have also been fewer stories of passengers being trapped in airplanes for hours on end. Still, summer weather will test the readiness of airlines and airports and will challenge the limits of this rule, as a recent incident demonstrates.

Virgin Atlantic flight number 1 from London Heathrow to Newark, New Jersey could not land at its intended destination due to thunderstorms in the area. On a good day, the New York airspace is one of the most delay-prone regions in the nation. Add some bad weather and you have the ultimate test of the 3-hour tarmac delay rule. For passengers of VS 001, the rule proved to be of no help to them as they were left on a tarmac at Bradley International Airport (BDL) near Hartford, Connecticut for 4 hours. Though an international airport, Bradley customs agents typically process cargo flights. The international flights to BDL are mostly from Canadian airports which often have pre-clearance facilities to process U.S.-bound passengers before departure. The airport was able to get customs agents back an hour after calling them in, according to airport officials, but by then the passengers had sat on the plane for over 3 hours without adequate air conditioning, food and water on board. It took over 4 hours before passengers were de-planed and on their way to their destination – by bus.

Unfortunately the tarmac rules have yet to compel non-U.S. carriers to provide contingency plans for long ground delays the way U.S. carriers operating international flights must. This will most likely change. According to the Associated Press, U.S. Transportation Secretary Ray LaHood has proposed extending the requirement for ground delay contingency plans to foreign carriers. The department is seeking comments from airlines and the public on whether the Department of Transportation (DOT) should also extend a firm three-hour limit to international flights by U.S. and foreign carriers. Currently, U.S. carriers operating international flights are not held to the 3-hour limit that applies to domestic flights but they must provide their own contingency plans for lengthy ground delays.

Implemented by the DOT in April, 2010, the tarmac delay rule requires that U.S. airlines on domestic flights delayed up to 3 hours on the taxiway allow passengers to deplane. This can be done by returning the aircraft to the gate or by transporting passengers to the terminal via bus or other means. Most airlines choose to return to the gate rather than face a stiff fine of US$27,500 per passenger. In doing so, the flight runs the risk of being cancelled due to crew scheduling and other issues. This is the "unintended consequence" most airlines have warned about, but early results indicate that the airlines are handling these delays better than expected.

IAPA has advocated for the coordinated implementation of contingency plans by airports, airlines and other entities to deal with extended tarmac delays. We are slowly seeing progress in this regard but the VS001 incident shows that more work needs to be done.

Airline captains list alternate airports in their flight plans in case of a diversion or emergency. It makes sense that if you are an airport operator and your airport is on that alternate list, you should be on alert for diverted flights when bad weather affects airports in your region. It's all about anticipation and preparedness. The airline and the airport claim that they did everything they could under the circumstances. Though that may be true, steps should have already been in place to accept the flight and process the passengers more quickly once the possibility of a flight diversion became real. If the rules had applied to international carriers in this case, perhaps any airline lacking the facilities or staff at a particular airport would still have been able to serve its passengers more adequately.