I don’t have any data on how much the new three-hour rule for tarmac delays has affected us over the last few months, and probably shouldn’t publish them if I did. But I do suspect that the next four months will provide the toughest test for the new rule.

Winter weather is one of the biggest challenges we face. Running an airline in any weather is difficult, and winter adds a host of complications including frozen precipitation, deicing requirements, variable runway traction, poor visibility, and our employees’ difficulty getting to work through the nasty weather. As I explained in more detail this spring, these factors combine to greatly increase the chances that some flights will need to wait on the tarmac for some time before takeoff or after landing.

This article in the Wall Street Journal discusses some of the airlines’ preparations for winter under the new rules and the impact they expect.

Don’t be fooled by one statistic in the article. The DOT argues that the airlines aren’t canceling significantly more flights. Citing September 2010 as an example, it claims the airlines canceled 0.9 percent of their flights compared to 0.6 percent in September 2009. September is one of the best weather months for a North American airline. The air is starting to cool, reducing the frequency and severity of tarmac-delay-causing thunderstorms, and Old Man Winter is still a couple of months away as well. It’s rare that an opportunity would exist for a three-hour tarmac delay in September. For a better measure of the rule’s impact, we’ll need to consider the number of cancelations for November through March. I suspect they’ll be significantly higher.

I can certainly understand why someone wouldn’t want to be trapped for hours on an airplane. I wouldn’t, either. However, the airlines must operate safely and legally above all, and sometimes we can’t achieve those goals without inconveniencing some of our passengers. Given the choice between a long wait on the plane and potentially having to wait a day or more to reach my destination, I’d rather take the delay unless I was traveling with my kids. If I could see that the weather could be a problem, I would plan ahead and bring some food, water, and plenty of entertainment just in case.