TPI Composites Inc.’s (Scottsdale, Ariz.) All Composite Military Vehicle (ACMV) prototype has successfully completed both accelerated durability testing and road testing. In a Jan. 19 statement to the press, the company said it believes the ACMV is the first all-composite tactical vehicle to reach such a milestone for the U.S. Army, and called it a significant step toward integrating advanced composite materials into all U.S. tactical military vehicles.
According to TPI, the first-of-its-kind prototype is built on the U.S. military’s existing High Mobility Multi-purpose Wheeled Vehicle (HMMWV) platform. The ACMV’s entire body structure, including the frame rails, is constructed of composite materials. The standard HMMWV drivetrain, suspension and other accessories are fastened to the composite body with methods similar to those used for steel and aluminum HMMWVs. The prototype reportedly cuts 900 lb/408 kg off the total weight of a conventional HMMWV, providing a lighter but more durable vehicle that can carry a greater payload while improving fuel efficiency. Further, it reduces vehicle corrosion and certain maintenance expenses.
The ACMV prototype was tested by Defiance Testing & Engineering (Troy, Mich.) in late 2009 on a four-post, tire-coupled vehicle test simulator. Then the vehicle was sent to Chrysler’s Chelsea Proving Grounds for 85 hours of testing that simulates 50,000 miles (nearly 80,500 km) of operation under severe off-road conditions — a regime referred to as “L4S,” commonly used for light trucks and sport utility vehicles. The vehicle also underwent tests at the Nevada Automotive Test Center (NATC, Silver Springs, Nev.) between December 2008 and May 2009 and was subjected to a number of performance tests, including dynamic stability. In addition, it was driven for 5,000 miles/8,047 km on a mission profile-representative course. The ACMV performed very well and exhibited no significant structural failures, says TPI. Blast testing is likely to take place in the first half of 2010. Among the project team members that supported the program was the University of Delaware’s Center for Composite Materials.