First-of-its-kind prototype reportedly saves 900 pounds versus traditional HMMWVs
SCOTTSDALE, Ariz.—A prototype All-Composite Military Vehicle (ACMV) developed by TPI Composites, Inc., is believed to be the first completely composite tactical vehicle to successfully complete accelerated durability testing and road testing for the U.S. Army. In tests conducted by Defiance Testing & Engineering (Troy, Mich.) between October 9, 2009 and November 2, 2009, and at Nevada Automotive Test Center (NATC) between December 2008 and May 2009, the ACMV reportedly performed very well while “exhibiting no significant structural failures.” According to TPI Composites, the milestone represents significant steps toward integrating advanced composite materials into tactical vehicles—a technology shift that will provide the Army with a lighter, more durable option for transporting troops and cargo over treacherous terrain. It is also expected to enhance personnel protection, improve fuel efficiency, reduce corrosion and certain maintenance expenses, and allow the addition of payload, such as vital communications systems or ammunition.
The military’s High Mobility Multi-purpose Wheeled Vehicle (HMMWV) was selected as the platform of the vehicle. The body structure of the ACMV, including the frame rails, was constructed of composite materials and contains no metal. Standard HMMWV drive trains, suspensions, and other accessories were fastened to the composite body via methods similar to those used for steel and aluminum HMMWVs.
“We are very pleased with the performance of TPI’s All-Composite Military Vehicle,” said Steve Lockard, CEO of TPI Composites, in a statement from the company. “A vehicle like this gives the U.S. Army several significant options to improve its HMMWV fleet. Not only will this vehicle give our troops increased mobility, its lighter, high-strength composition will allow for significant fuel efficiency and potentially allow for the addition of enhanced armor or greater payload. This is a huge step forward in military vehicle engineering.”
At Defiance Testing & Engineering, the ACMV prototype was tested on a 4-post tire coupled vehicle test simulator. The vehicle was sent to Chrysler’s Chelsea Proving Grounds for 85 hours, representing a 50,000 mile road test. The data represented a severe off-road schedule typically used for light trucks and sport utility vehicles, commonly referred to as “L4S.” The vehicle was tested in two different configurations—ballasted and un-ballasted. Other project team members that supported the program included the University of Delaware’s Center for Composite Materials.
At the NATC, the ACMV was subjected to performance tests that included static stability (tilt table); dynamic stability (NATO double lane change); dynamic stability (steady state turning); ride quality and peak acceleration; and peak vertical acceleration. The vehicle was also tested for 5,000 miles on a mission profile-representative course. The road test consisted of 1,500 miles of primary roads, 1,500 miles of secondary roads, and 2,000 miles of cross-country travel.
“We’re proud to apply our expertise in composite technology to assist the military in providing a lighter, safer, more durable vehicle for U.S. troops,” said Lockard. “From our beginnings as a custom yacht manufacturer to the wind turbine blades we supply to GE Energy and Mitsubishi Power Systems to our military products, TPI has a heritage of innovation in composite manufacturing.”
The next and last significant phase of testing of the ACMV is blast testing, which the company said was likely to take place in the first half of this year.
This isn’t the first time that TPI has applied advanced composites to military vehicles. The company has designed and built improved HMMWV Mine Resistant Ambush Protected (MRAP) hoods, and has also designed and prototyped the first All Composite Cab for the Heavy Expanded Mobility Tactical Truck (HEMTT) platform. Like the ACMV, the HEMTT cab has successfully completed several tests required by the Army. In each case, TPI says, it has significantly reduced vehicle weight and produced parts that enhance vehicle payload and personnel protection.
TPI Composites (www.tpicomposites.com), based in Scottsdale, Ariz., is a rising supplier of turbine blades to the wind energy industry, in addition to serving the transportation and military vehicle markets.
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