Summary: In January 1980, GAO recommended to Congress that production of the XM-1 tank proceed at a low rate in view of continuing reliability and durability problems, particularly with the turbine engine. It also recommended the start of a back-up diesel engine program should a blue ribbon panel, which had been evaluating the tank's program, continued to have reservations about the turbine engine's performance. Having studied the panel's assessment, GAO has not changed its position. The panel concluded that considerable progress had been made towards achieving the power train's long-term durability goal, but it noted several deficiencies. It suggested continued performance evaluation and environmental testing. GAO believes that some of the panel's statistics should be qualified as possibly not being truly indicative of the tank's reliability in an operational environment. The Department of Defense (DOD) has chosen to follow a high risk acquisition policy for the XM-1. It has structured the program so that it relies on the successful concurrent development of a turbine engine, a type of propulsion system that has never proved itself adaptable to a tank. GAO believes that DOD should continue producing the tank with the turbine engine at a low production rate and simultaneously fund the development of a diesel engine to protect against the turbine engine's failure to meet reliability goals.
