NEW YORK (Bloomberg) — American Airlines stranded passengers on the runway more than any other US carrier in the past half-year, trapping them for hours often without water or working toilets, according to a passengers group.Grounded travellers sat for at least four hours on 101 American or American Eagle flights, according to the Coalition for an Airline Passengers' Bill of Rights. The recent strandings are particularly notable, the group says, because federal agencies exclude them due to a glitch in how data are collected.

The coalition, which compiles reports from 15,000 members, is urging US lawmakers to craft rules that would force airlines to release passengers after three hours' wait and to stock food and water for delays.

"Prisoners of war have more rights than passengers on an airliner," group founder and real estate agent Kate Hanni, 46, said at a news conference yesterday. In December, she was stranded for nine hours on a grounded flight in Austin, Texas, with no drinking water and a packet of pretzels.

Tim Wagner, a spokesman for American Airlines parent AMR Corp. of Fort Worth, Texas, didn't immediately return a call requesting comment. American is the world's largest airline.

The US Department of Transportation does record runway delays, counting 36 lasting five hours or more among all airlines last year.

Critics, however, say the government ignores delays in two instances that especially frustrate travellers: cancelled and diverted flights.

Flights that sit on the runway for hours and are then cancelled and sent back to the gate generally aren't included in federal stranding statistics, the coalition says.

Nor are flights that are diverted in mid-air to a different airport, where passengers can sit for hours upon landing, waiting to deplane.