Military Safety: Army M939 5-Ton Truck Accident History and Planned Modifications

NSIAD-99-82 April 9, 1999
Full Report (PDF, 24 pages)  

Summary

Two U.S. Army Reserve soldiers were killed during a training exercise at an Army installation in 1997 when the M939 five-ton cargo truck they were riding in overturned. Analyses by GAO and the Army found a higher rate of accidents involving the M939 than other comparable vehicles. Although M939s made up about nine percent of the Army's motor vehicle fleet between January 1987 and June 1998, these trucks were involved in about 34 percent of the fleet's fatal accidents. Moreover, 44 percent of accidents that involved a rollover and caused fatalities among vehicle occupants involved the M939. GAO also found that during a 10-year period, the fatality rate among occupants of the M939 was about 30 times higher than the fatality rate for occupants of comparably sized commercial trucks. An Army analysis found that the chance of a fatality in a M939 was three to 21 times higher than in similar Army trucks. The Army plans to spend an estimated $234 million on modifications to improve the M939's safety and operational performance, including anti-lock brake kits, upgraded tires, and cab rollover crash protection. Most modifications should be done by 2005. The M939s will remain in service as these changes are made.

GAO noted that: (1) GAO's analyses and an Army analysis indicate a higher rate of accidents involving the M939 series 5-ton tactical cargo truck than other comparison vehicles; (2) GAO's analysis of January 1987 through June 1998 accident data showed that, while M939s made up an average of about 9 percent of the Army motor vehicle fleet during that time, about 34 percent of the fleet's accidents resulting in fatalities of vehicle occupants involved these trucks; (3) 44 percent of accidents that involved a rollover and resulted in fatalities of vehicle occupants involved the M939; (4) GAO's comparison of Department of Transportation accident statistics and M939 accident statistics showed that over a 10-year period, the fatality rate for occupants of the M939 averaged about 30 times higher than the fatality rate for occupants of comparably sized commercial trucks; (5) an Army Safety Center analysis found that the chance of a fatality in a M939 was 3 to 21 times higher than in other similar military trucks in the Army motor vehicle fleet--the M34/M35 series 2 1/2 ton trucks; (6) the Army plans to spend an estimated $234 million on various modifications to improve the M939's safety and operational performance; (7) based on the results of studies into the root causes of M939 accidents, the Army concluded that the overall truck design was sound, but some modifications were necessary; (8) the Army plans to use the $234 million to add anti-lock brake kits, alter brake proportioning specifications, upgrade the truck's tires, install cab rollover crush protection, and modify the accelerator linkage; (9) most modifications will be completed by 2005; and (10) the M939s will remain in service as these modifications are made.