The Bureau for Transportation Statistics recently found that complaints about air service are on the wane. Nevertheless, the DOT division now offers reports on airline on-time performance, as well as delay cause statistics.

For the month of November, this active business traveler is surprised. Sure, 80% of flights are on time. But for as much hassle as it is to get information about delays and their cause while at the airport, it turns out that weather delays -- those acts of the gods the airlines aren't responsible for -- makes up less than 1% of all delays. Yet delays that might rate refunds are higher than I expected:

• More than 4% of delays stem from the air carrier themselves
• Almost 9% result from the national aviation system
• Late arrivals account for almost 4%

Are airlines only responsible for delays caused by mechanical breakdowns? Or are those who fly the friendly skies keeping mum for more than one reason?