According to a new study, the recently enacted DOT regulations that levy huge fines against airlines for planes that sit on the tarmac for more than three hours have been forcing carriers to cancel flights rather than face possible stiff penalties.

In May alone, researchers claim that at least 140 flights were canceled rather than face potential tarmac delays and possible fines of up to $27,500 per passenger.

According to the study, the number of flights canceled after 2-3 hour tarmac waits has increased 41% while diversions have increased 26%.

“Uncertainty about enforcement has driven severely risk-averse behavior by airlines,” explained the researchers about their findings.

The researchers have written to Transportation Secretary Ray LaHood, asking for DOT to clarify how it plans on enforcing the rule, especially for minor infractions of only a few minutes. Their hope is that, if airlines can be reassured that they won’t face a multi-million dollar fine for going 1 minute over the limit, they won’t preemptively cancel or divert that flight.

Flight cancellations climb under new tarmac rules [Chicago Tribune]

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