Recently developed heavy-equipment simulators from Caterpillar help both civilian and military trainees develop basic skills without burning fuel or risking the real-world consequences of a rookie mistake.

Until about five years ago, the only way to practice operating an excavator or bulldozer was to climb aboard and start moving dirt, ideally in an area without too many buried power lines and gas mains. Today, however, many technical schools, unions, and other training providers rely on computerized heavy-equipment simulators to teach this skill. Both Caterpillar and John Deere make simulators for their excavators, bulldozers, graders, rubber-tired loaders, and other machines.To a military or commercial pilot familiar with modern flight simulators - which cost millions of dollars and provide an experience almost indistinguishable from that of flying the actual...