What seemed like a good idea to save the taxpayers' money turned out to be a flop. That's what congressional investigators reported to a Senate subcommittee looking into the Defense Travel System, known as DTS.

The idea was an online travel booking system that was supposed to save on paperwork and travel agents. It was also supposed to find the cheapest tickets.

Sen. Norm Coleman, R-Minn., ordered a further study and said investigators found that most Pentagon travelers do not use the system.

"Close to 80 percent of the folks in the Defense Department are simply picking up the phone, calling a travel agent, because it's easier, it's more complete, and in the end, it will cost the taxpayer less money," Coleman said.

Coleman cited the newest figures showing that out of about 755,000 trips taken at 42 Department of Defense locations, only 17 percent were arranged through DTS.

Coleman and a fellow Republican, Oklahoma Sen. Tom Coburn, want to kill the system. Coburn called DTS "a hoax on the American taxpayer." But this fall, Congress voted to spend another $60 million on DTS for a total cost of $474 million.

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