While developing FlightStats, I ran accross several bugs in the data I got from the Bureau of Transportation Systems. I reported the data to them, and got a quick response back (two weeks) that they had confirmed the bugs and asked the airlines to correct their reporting.

Did they? Yes! (Well, mostly. Grr, Southwest.)

Airline: Southwest
Initial Report: February 6, 2004
Reply: February 18, 2004
Problems Fixed: 30% in March, 2004 data set.

Airline: US Airways
Initial Report: February 6, 2004
Reply: February 18, 2004
Problems Fixed: 100% in February, 2004 data set.

Airline: American Eagle
Initial Report: July 21, 2004
Reply: None?
Problems Fixed: 100% in July, 2004 data set.