But while Hanni spun her wheels, airlines continued to hold passengers hostage on more and more flights. Depending on whose numbers you believe, more than a thousand flights a year were being held incommunicado on airport tarmacs for more than three hours.

Then came August 2009 and Continental Express Flight 2816. During a patch of bad weather, the tiny regional jet was diverted to Rochester, Minnesota, and spent the night sitting on the tarmac. Continental Airlines, whose name was on the plane, didn't act forcefully enough to convince its commuter partner, ExpressJet, to get the aircraft to the terminal. And the airline in charge of overnight operations in Rochester, Mesaba, refused to open the terminal and let the passengers on Flight 2816 disembark.

This time, however, the Department of Transportation acted. It slapped a combined fine of $175,000 on the three carriers, the equivalent of more than $3,700 for each of the 47 passengers who spent the night in Rochester. The airline industry was stunned by the severity of the fine. Passenger's rights advocates, including Hanni, took the credit—even though many of them previously claimed that DOT action would never be sufficient to stop excessive "tarmac holds."

Finally, just before Christmas, a full decade after Northwest Airlines abandoned flyers in Detroit, Transportation imposed new rules. To Hanni's everlasting credit, the department's regulations essentially codify the major thrust of her unsuccessful legislation: Airlines operating domestic flights must permit passengers to disembark a flight if they have been held for three hours or more without a departure. The only exceptions: safety or security concerns or if air-traffic controllers inform the pilot that disembarking passengers or returning to the gate would disrupt airport operations. Other portions of Hanni's proposals, including making food, water, and lavatory facilities available to stranded passengers, are incorporated into the DOT rules too.

But the Transportation Department put a financial incentive into its regulations: Airlines can be fined as much as $27,500-per-passenger if they violate the new rules. As the DOT's penalty in the Minnesota case last summer proved, it's not bad publicity or photogenic activists that the airlines fear, it's the threat of having to pay cold, hard cash if they hold passengers hostages.

Will the new passenger's right regulations end long tarmac holds and stop airlines from treating its customers like chattel? Hard to say. But we do know that the airlines are scrambling to put new procedures in place to avoid the possibility of getting slapped with punitive fines.

That, at least, is a start. Eleven years late, perhaps, but a start nevertheless.

The Fine Print...

The DOT order also "prohibits airlines from scheduling chronically delayed flights." That provision is probably toothless because it won't stop airlines from dodging the rule simply by renumbering flights with bad on-time ratings. The carriers are also disputing a provision that would require them to post on-time ratings for each of their domestic flights on their respective websites.

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