CAMP ARIFJAN, Kuwait - Maintenance experts with the 401st Army Field Support Battalion-Kuwait are key for ensuring the quality of vehicles at Army Prepositioned Stocks-5, one of the largest stocks of modern ground-force equipment in the world.Imagine parking lots upon parking lots packed with military vehicles loaded with equipment worth a combined value of more than $5 billion. Now imagine how much work must go into keeping that stuff mobile."Saying it's a huge responsibility to maintain the vehicles here is an understatement," said Sgt. 1st Class Matthew Zakrzewski, maintenance quality assurance, 401st Army Field Support Battalion-Kuwait. "People's lives are on the line, and what we do affects their ability to accomplish the mission."If we don't do our job, the warfighter can't do theirs' and that's not acceptable," Zakrzewski said.The APS-5 Maintenance Quality Assurance office has more than a dozen certified Soldiers at any given time, each with a different 91-series (mechanical maintenance field) military occupational specialty.APS-5 has thousands of tracked and wheeled military vehicles, including M1A2 Abrams Tanks, M2 and M3 Bradley Fighting Vehicles, and a wide range of Mine Resistant, Ambush Protected vehicles (MRAPs).Zakrzewski said he understands the importance of his current job having pulled equipment out of similar sets before, once in 2003 for operations in Iraq and again in 2007."When I am working on a vehicle, I think about how important it is that it works when the guys who need it use it," said Zakrzewski, who is an expert on the Bradley Fighting Vehicle."Most of the people who work in our office have been to combat before, so they know the kinds of things Soldiers could face when these vehicles are drawn out," he said.The role of ASP-5's quality assurance personnel is to oversee and direct the work contractors do to keep the equipment to the Army's standard."We hold the contractor to standard by inspecting the equipment to make sure it's [fully mission capable] for whatever mission it may have down the line," said Sgt. 1st Class Roy Carson, maintenance quality assurance for wheeled vehicles, 401st AFSBn-Kuwait."I am held to a high standard, and I make sure the contractor is too," he said.The process for validating a contractor's work depends on the type of equipment being examined. For vehicles, all of the usual suspects are checked, including lights, wheels, and drivability. However, systems built-in to the vehicle must also be checked.For example, when components are fixed on a Bradley Fighting Vehicle, every system is checked, including the tracks, doors and everything in the turret."Troubleshooting a turret is difficult," said Zakrzewski. "There are multiple different components talking to each other at the same time, so if the weapon won't fire, there could be multiple reasons for that."Onboard diagnostics and the internet can't always save you," he continued. "You have to know everything that component or that part of the vehicle is supposed to do in order to isolate the problem."Once the contractor identifies a needed repair, a contracting officer's representative (COR) checks to validate the problem and, if necessary, parts are ordered. All of APS-5's maintenance quality assurance personnel are also CORs.With regular COR-lead checks on performance in accordance with each contract, the contractor then completes the repair. The COR then checks all key aspects of the repair and the general functionality of the equipment. Finally, the COR decides to accept or reject the vehicle's reintroduction to the equipment set.In a typical week, Carson said he does approximately 60 inspections on more than 20 types of equipment, from the PLS 1076 Trailer to the armored M1165 HMMWV. His original specialty was in power generators."Everybody placed in this assignment is trained," said Carson. "What I've seen is everyone here is very efficient and they go by the book. We are the subject matter experts of our fields."Carson said it's ultimately about maintaining good relationships with everyone doing the work."Building trust gives the team confidence to bring issues forward that need to be addressed," he said. "It's our job as quality assurance to address those issues, so having contractors and all the members of our team on the same page is important.""Ultimately, we are the professionals who take care of the equipment so the equipment can take care of the warfighter - that's our focus," said Carson.A significant amount of the equipment at APS-5 is what the maintainers here call "combat configured," meaning vehicles are staged with many of the items the warfighter needs before they arrive in theater.In the past, vehicles and equipment would be stored in a deeper dormant state, with different fluids to keep the equipment in a better condition for longer. This meant it took significantly more time to prepare it for use."The combat configured process requires more work for us, but dramatically increases the warfighter's deployment speeds," said Sgt. 1st Class Robert Ford, maintenance quality assurance for tanks, 401st AFSBn-Kuwait. "A lot of our equipment could be issued immediately, with full units leaving in mere hours if necessary."For configured equipment, only things not already mounted on or with the vehicles are Soldier technologies that require higher levels of security, including weapons systems and radios.APS-5 is a massive combination of military vehicles, weapons and tools staged to provide strategic planners with options in the case of contingency operations across U.S. Central Command's area of responsibility.The readiness rate of APS-5 equipment is above the Army's standard of 90%.APS-5 includes enough equipment to outfit multiple ground force brigades and various transportation watercraft.The 401st AFSBn-Kuwait employs the Soldiers, civilians, and contractors who maintain the bulk of APS-5.The battalion is a subordinate of the 401st Army Field Support Brigade, which is responsible for connecting CENTCOM logistics operations to the rest of the Army's materiel enterprise.