After sitting on the tarmac for five hours waiting to take off, the passengers on Independence Air Flight 1128 felt anything but independent.

The flight was supposed to take off from Boston's Logan International Airport at 1:15 p.m. Wednesday. But because of yet another harsh stream of thunderstorms blowing into the Washington area, Dulles International Airport was not accepting incoming flights.

So the passengers sat on the 50-seat plane on the tarmac with little air conditioning for nearly four hours. The aircraft finally returned to the gate at 5 p.m. Twenty-five minutes later, passengers were ordered to quickly get back on board. The plane made its way down the runway, only to sit again, for another hour.

The plane finally took off from Boston at 6:40 p.m. and arrived at Dulles at 8:50, nearly eight hours after scheduled departure. It was just about the same amount of time it would have taken the passengers to drive.

"We felt a little captive on there and people were getting angrier and angrier each moment," said passenger Maryanne Hellender of Potomac. "If we had been on there any longer, it would have been mutiny on Independence Airlines."

This sort of captivity was supposed to end after a couple of incidents several years ago -- in which Northwest Airlines and United Airlines trapped passengers on grounded planes for eight hours -- prompted all of the major airlines, under threat of legislation from Congress, to adopt so-called passenger bills of rights. Those rules spelled out how they would inform customers of delayed or canceled flights and how they would treat them during "extended" waits for departure.

In his 2001 report to Congress on airline customer service, Department of Transportation inspector general Kenneth Mead said the airlines should clarify what they meant by an "extended" period so that "passengers will know what they can expect."

"Airlines differ in what qualifies as 'extended,' " Mead said at the time. "The trigger thresholds for this provision vary from 45 minutes to three hours. We think it is unlikely that a passenger's definition of an 'extended' on-aircraft delay will vary depending upon which air carrier they are flying."

Just three months after Mead's testimony, the Sept. 11 terrorist attacks occurred, forcing the airlines to focus on other issues and leaving those vagaries undefined.

But Independence passenger Hellender said that the airlines should be forced to revisit the issue.

"There should be a federal law or ruling on how long people can be kept on the airline," Hellender said.

Aaron Kahn, a passenger on the Independence Air flight, immediately contacted Biz Class after arriving at his Lovettsville, Va., home following the ordeal.

"We kept getting misleading information. They kept saying after an hour we'll make a decision about going back, but after the hour was up, the captain would come on and say we're going to wait another hour and see what happens," Kahn said.

The sole flight attendant on the plane passed out drinks and pretzels to the passengers during the wait. And the passengers were allowed to use their cell phones. But what these travelers wanted was the option to get off the plane and either try to find an alternate flight or just go to a hotel for the evening and try again the next day.

It turns out that Flight 1128 would have been the first flight cleared to take off from Boston once the ground hold by air traffic control was lifted, and the captain did not want to risk losing that position by returning to the gate.

Rick DeLisi, a spokesman for Dulles-based Independence Air, said the airline's procedures called for the crew to take a vote of the passengers to see if the majority wanted to wait it out on the tarmac or instead return to the gate. But it turns out the vote was not taken. Instead, the crew tried to wait out the ground stop so they could take off, but the air traffic controllers kept extending the delay.

"This situation was totally unacceptable to us. We have immediately changed our own policies to ensure this kind of thing never occurs again," DeLisi said.

Independence has implemented a rule that if a flight is on the tarmac for up to two hours, it must return to the gate.

A survey of other airlines found that few have a time limit during such incidents. Northwest was the only major carrier that had a time limit on taxi-out delays. After three hours on the tarmac, a Northwest flight must return to the gate, said Northwest spokeswoman Mary Stanik.

Other carriers have very loose guidelines. US Airways and Delta decide what to do in these incidents on a case-by-case basis and have no time limits. United determines how long a flight stays on a tarmac by polling its passengers.

As an apology to the 20 or so passengers on the delayed Logan-Dulles flight, Independence offered each of them a credit of $525 -- the equivalent of four or five flights -- for future travel on the airline.

"There's nothing about this story that makes us happy in any way. We will make sure that nothing like this could ever happen like this again," DeLisi said.

Question of the Week: If you take your kids on business trips with you, what advice would you give to people thinking about whether to try it? Please send your name and daytime phone number to alexanderk@washpost.com.

Staff researcher Richard Drezen contributed to this column.