For the second time in five years, Pentagon inspectors are criticizing Hill Air Force Base for the way it tracks and maintains part of its fleet — not its signature 1,500-miles-per-hour F-16 fighter jets, but the 25 mph "low-speed vehicles" (LSVs) that it uses to putter around the base.

It may sound funny, but the Air Force Audit Agency is stone-cold serious.

After looking at how five bases worldwide, including Hill, take care of such vehicles, it complained they did not "perform and document required maintenance," nor did they "maintain accurate accountability" — not even knowing how many LSVs they had, or when or if they had been serviced.

It said that potentially costs the Air Force big money, and hurts its efforts to convert a third of that fleet to nonpetroleum fuels such as natural gas or electricity.

That's according to reports obtained by the Deseret News through Freedom of Information Act requests.

Inspectors wrote they conducted the new review both to see if problems found in 2004 had been corrected, and to ensure the Air Force is complying with congressional mandates to reduce its dependence on petroleum-based fuels. The trouble is, inspectors found that Air Force records about the size of the LSV fleet were full of errors and holes.

For example, one report said seven LSVs (such as small trucks that are street-legal but operate at 25 mph or less) found at Hill were not on any inventory lists. Also, another 46 golf carts or four-wheelers (that are not street legal, and therefore technically not "LSVs") also were not on any inventories.

Another report said six LSVs that were listed on inventories at Hill were missing.

As inspectors noted, accuracy on inventories is needed to "plan future purchases, identify losses or theft of government resources, assign liability when assets are lost, and identify current stock levels in support of mission requirements."

Many vehicles that managed to be included on inventories actually were on the wrong type of lists, inspectors complained.

That makes a difference because different organizations are responsible for different types of vehicles. LSVs, for example, are now bought centrally by the Air Force and it is responsible for their maintenance, while other carts often are considered equipment that is bought and maintained locally.

At Hill, for example, it found 78 golf carts and four-wheelers improperly listed on inventories as street-legal LSVs. And it found five LSVs improperly on lists for the other slow vehicles that are not street legal.