This article discusses that event-simulation software can help engineers improve the safety of a military transport vehicle, while reducing the number of prototypes and shortening the design cycle. US Army's Tank and Automotive Command (TACOM) unit brought the truck's frame design to AM General with recommendations for a rollover protection structure. The AM General design team created plans for a T-shaped configuration to be added to the original truck frame that would protect occupants during a rollover accident. AM General stress analyst performed finite element analysis with Mechanical Event Simulation, including both Linear and Nonlinear Stress Analysis software from Algor Inc. of Pittsburgh. When the prototype asses its laboratory test, AM General will immediately manufacture an additional 20 units for both physical and field testing. This may include an armored variant for field testing in Bosnia, an area with rugged topography. TACOM plans to modify other M 939/A1 / A2 series trucks on an as-needed basis; they will install the rollover protection structures on trucks in use where conditions like rough terrain make rollover accidents more likely.