General Dynamics Corp.'s $15.5 billion Expeditionary Fighting Vehicle program, to build amphibious transports for carrying Marines ashore, should be considered for cancellation, according to congressional auditors.

The project is at least five years behind schedule and, at $24 million apiece, 176 percent over its original per-unit price tag, according to a U.S. Government Accountability Office report. It faces additional "cost, schedule and performance risks," said the report, released today by Congress's investigative arm.

The "program's history of cost growth, schedule slips and performance failures" -- combined with the increased threat of anti-ship missiles against Marine Corps vessels -- "raise the question of whether the case for the program is still sound," the report said.

General Dynamics spokesman Peter Keating said the Falls Church, Virginia-based company's land systems unit has delivered four of seven new prototype vehicles with reliability improvements to Camp Pendleton, California, for 18 months of testing. The remaining three transports will be delivered this month.

"We have fixed everything and we are going to demonstrate performance," Keating said. "If we can't prove it in 18 months of testing, then shame on us."

The transport program has been in development for more than 10 years and was reorganized in 2007, cutting the number to be purchased and extending the development period, after the vehicle failed earlier reliability tests.