(CNN) -- The new airline tarmac delay rule seems to be working. October was completely free of tarmac delays lasting more than three hours, according to the latest Department of Transportation air travel report released Tuesday.
In October 2009, 11 flights experienced such delays. There have been 12 delays this year from May to October, compared to 546 during the same period in 2009.
A new aviation consumer rule went into effect April 29 threatening hefty fines for airlines that keep passengers on the tarmac for more than three hours.
The rate of canceled flights in October was in line with last year, dropping from 0.99 percent of scheduled domestic flights last October to 0.97 in 2010.
October 2010 marks the first month free of delays of more than three hours since the transportation department started collecting more tarmac delay data from reporting airlines in October 2008, the department said.
"We appreciate the effort the airlines are putting into making this new rule work effectively for the benefit of their passengers," U.S. Transportation Secretary Ray LaHood said in a statement.
On-time performance in October was nearly 83.77 percent, above the average of 80.72 percent for October in the past 15 years, according to the Bureau of Transportation Statistics.