Aug. 11 (Bloomberg) -- Continental Airlines Inc. must explain why passengers on a flight were kept on a plane all night on the ground in Rochester, Minnesota, Transportation Secretary Ray LaHood said today.

LaHood said he sent a letter to Continental asking why the flight, operated by ExpressJet Holdings Inc., was diverted, and which carrier was responsible for the passengers. He is also checking whether any laws were violated, saying in a statement that “this incident as reported is very troubling.”

Passengers were on an almost full 50-seat jet from about 12:30 a.m. to 6:30 a.m. with “pungent” air, no food offered and two babies crying, passenger Link Christin said today in an interview. “People were getting sleep-deprived,” he said.

The incident on Aug. 8 in Rochester, about 90 miles south of Minneapolis, will bolster efforts to enact a federal requirement that airlines allow passengers off grounded planes after three hours, said Kevin Mitchell, chairman of the Business Travel Coalition in Radnor, Pennsylvania.

“It’s going to have an enormous impact,” Mitchell said. “I can see members of the House jumping on this as a consequence of all the press coverage.”

A Senate panel approved legislation last month with a three-hour standard. LaHood’s agency is drafting a rule that could include the requirement. “We will use the information Continental provides to help us reach a decision about what direction to go in that rulemaking,” LaHood wrote.

Tarmac Delays

Continental said in a statement that it is offering passengers an apology, refunds and travel vouchers.

“We recognize that service provided to customers on this flight was completely unacceptable.”

Julie King, a spokeswoman for Continental, said in a separate statement that the company is “working with the DOT to respond quickly to their inquiry regarding flight 2816.”

An ExpressJet representative didn’t return messages. ExpressJet operates Embraer regional jets for Continental, the fourth-largest U.S. airline. Both carriers are based in Houston.

An ExpressJet spokeswoman told the Associated Press that the passengers couldn’t go to the terminal because they would have to go through security screening to board the aircraft again and the screeners had gone home.

“There needs to be some common sense used in these cases,” said Senator Byron Dorgan, a North Dakota Democrat who chairs the Senate aviation subcommittee, according to his spokesman, Justin Kitsch. “These folks have a right to complain.”

Fending Off

Airlines have been trying to fend off a three-hour limit since flights that waited for as long as 10 1/2 hours in late 2006 and early 2007 put tarmac delays in the national spotlight. Carriers say they should decide when to release stuck passengers, and that loss of flexibility could worsen delays.

“Airlines understand passengers’ frustration,” the Washington-based Air Transport Association carrier trade group said in a statement. “We continue to believe that a hard-and- fast rule requiring mandatory deplaning of passengers after three hours will have substantial, unintended consequences.”

Mitchell said his group of corporate travel managers doesn’t yet have a position on the three-hour standard. Carriers have invited additional regulation by not moving quickly enough to prevent the long delays, he said.

U.S. airlines had 278 tarmac delays of three hours or longer in June, the most of the nine months in which the government has been keeping detailed statistics. The 278 represented 0.05 percent of flights that month, according to the Bureau of Transportation Statistics.

The figures “further prove that there’s no will on the part of the airlines to fix the problem,” Kate Hanni, executive director of FlyersRights.org, said in an interview. The Napa, California, group has been pushing for a three-hour limit.

The passenger on the flight, Christin, 56, an adjunct law professor who lives in St. Paul, Minnesota, said it would be “terrific” if his experience helped bring about a three-hour limit.

“I would be proud,” he said.

To contact the reporter on this story: Angela Greiling Keane in Washington at agreilingkea@bloomberg.net To contact the reporter on this story: John Hughes in Washington at jhughes5@bloomberg.net

Last Updated: August 11, 2009 17:47 EDT