U.S. Rethinks Air Travel Screening

Testing of the system, which is known as CAPPS II and has cost more than $120 million, was supposed to begin this summer.

Officials gave no timetable for the Transportation Security Administration to develop a new version.

"We are working on developing the next-generation passenger pre-screening system, but the program you knew as CAPPS II is essentially halted," said Mark Hatfield, a spokesman for the security agency.

Some lawmakers said computerized passenger screening should be scrapped. Instead of investigating millions of ordinary people, they said the government should promote a registered traveler program for frequent fliers who volunteer for background checks.

These passengers would speed through special airport security lanes, allowing for more efficient screening of the remaining travelers. A small percentage of people are frequent fliers, but they account for a large percentage of airline passengers.

"If you expedite the screening of frequent fliers, everybody would come out ahead," said Rep. Peter A. DeFazio (D-Ore.). "It would allow TSA to focus on unknown threats. It would reduce the security lines. And it would benefit the airlines, because these are their high-revenue passengers."

The government is testing the concept at several airports, including Los Angeles International Airport, in a 90-day pilot program this summer.

United Airlines began accepting applications Thursday from its frequent fliers for the Los Angeles program, said Nico Melendez, an agency spokeswoman.

CAPPS is an acronym for Computer Assisted Passenger Pre-Screening. The airlines now use a rudimentary version that focuses on unusual behavior patterns, such as paying cash for tickets or buying a one-way ticket. Passengers flagged by the current system have a mark stamped on their boarding passes and are more thoroughly searched by federal screeners.

One of the goals of CAPPS II was to reduce the number of travelers subject to more intrusive searches. But critics of the system, both liberals and conservatives, objected to the computerized background checks that were at its heart.