For 16 years, the U.S. Army Research Institute of Environmental Medicine (USARIEM) has provided microclimate cooling for helicopter pilots flying into desert or jungle heat. The pilots plug into the systems and are able to keep cool. However, the tethers that connect them to the aircraft-mounted cooling systems can become tangled and limit free or fast movement. At the Natick Soldier Systems Center in Natick, Mass., USARIEM is testing technology that cools and allows freedom of movement. The Light-Weight Environmental Control System (LWECS) body-worn microclimate system consists of a cooling vest with 110 feet of tubing through which refrigerant can pass, a cylinder full of coolant and a plate-like battery that can fit inside body armor. At Natick’s Doriot Climatic Chambers, volunteers wearing chemical-protective gear have been simulating 11-hour missions in desert and jungle heat, with researchers monitoring the results. “We’re seeing that their body core temperatures are lower, their heart rates are lower,” says Bruce Cadarette, a USARIEM research physiologist. For crew chiefs unloading cargo or medics hurrying to treat wounded soldiers in the field, moving fast and keeping cool may make a life-saving difference. For more details, visit www.usariem.army.mil.