TWENTYNINE PALMS, Calif. -- He peered out of a hole barely big enough to fit his body through as he carefully maneuvered the 26-ton amphibious assault vehicle into formation. He lowered his goggles to protect his eyes from the billowing sand and waited eagerly for the command to move out.Corporal Tyler L. Otten, a crew chief with 3rd Platoon, Alpha Company, 2d Assault Amphibian Battalion, 2d Marine Division, Camp Lejeune, N.C., along with other Marines from his unit, set out for the open terrain of the desert recently to get a feel for the environment they will train in while participating in Combined Arms Exercise 3-01 here.According to 2nd Lt. Jason P. Smith, Otten's platoon commander, the open space of the desert allows his Marines to work in a more combat-realistic environment."CAX gives us an opportunity to work in a different type of terrain than we are used to," said Smith. "We can do true formations with the vehicles because of the huge training areas." The commander of the 'Black Sheep' Platoon added his unit is less restricted here than on the training areas at Lejeune, and his Marines are able to do live-fire maneuvers. "The training out here is more realistic than we would normally get at Lejeune," said Smith of Cheney, Wash. "At Lejeune you are confined to the roads and here you can drive pretty much anywhere."While the unit has miles of driving space available to them, there are frequent stops made and routine checks done on the vehicles to ensure they are functioning properly in their new environment."Whenever we stop I do routine checks on the vehicle," said Otten of Jirard, Ill. "It is important to make sure that no concertina or communication wire has entangled itself in the tracks."He added checking the suspension is key while out here in the rough terrain, but the fielding of a new track system has allowed better movement and less damage to the vehicles."They just started fielding these new tanks (vehicles) last year," Smith remarked. "The whole suspension system has been lifted so the tracks can move better over rough terrain."In addition to his maintenance responsibilities, Otten's position as the crew chief puts him in the 'turret' where he is in control of the vehicle's weapon system."The crew chief normally rides in the turret and fires the weapons," said the 20-year-old. "We can fire 200, .50-caliber rounds from the M-2 automatic machine gun and approximately 96 grenades from the grenade launcher before needing to be restocked." Another essential part of a successful ride is the proper function of the communication system. "Communication between the crew members is important," said Lance Cpl. David W. Mueller, a communication technician with the unit. "The intercom system is what links them all together."Smith added the training the 'Black Sheep' will receive here is a large portion of the preparation for its upcoming deployment with the 26th Marine Expeditionary Unit.