Starting Saturday, some travelers will begin providing their birth date and sex when booking their airline reservations.

It's the second part of the government's phased-in program, Secure Flight [1], to match passengers' names against the government's terrorism watch list. Earlier in the summer, when passengers booked their online travel they had to provide the airline with exactly how their name appears on their government-issued identification card—whether it be a driver's license or a passport.

But not all travelers will be asked for the information, reports The Washington Post [2].

Passengers should not be concerned if their airline does not ask them for the information, [Transportation Security Administration spokesman Greg] Soule said. The agency hopes to vet 100 percent of domestic passengers by March 31 and all passengers on international flights to, from or over the United States by the end of 2010 -- a total of 2 million daily passengers.

For now, there will be no penalty for passengers who do not provide the information, Soule said. However, once the program is fully implemented, they could be denied boarding passes, he said.

"We have been assured that no passenger will be turned away or be denied the ability to travel," said David A. Castelveter, a spokesman for the Air Transport Association of America, a domestic airline trade group. "It would simply mean if you didn't have the information, you would be subjected to secondary screening."

Previously, it was the responsibility of the airlines to collect passenger names and match them to the watch list. Rampant misidentifications and false matches, however, led Congress to hand over that responsibility to the TSA.

TSA believes that by passengers providing their name exactly as it appears on their government ID, their birth date, and their sex, only about 1 percent of passengers per day—about 2,000 says the Post— will experience delays.

When discrepanies arise between passenger information provided to the government from the airlines and the passenger's ID, additional screening may occur.

For travelers a bit skeptical of the new program requirements or worried they will be delayed or denied boarding, The New York Times answers some common concerns [3] percolating throughout the frequent flying community.

The TSA, in partnership with the Ad Council, has also produced a video explaining Secure Flight.

♦ Photo of TSA secondary screening by Crashworks/Flickr [4]

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