December 28, 2005:
After more than five years of effort, vehicle crews in Iraq are getting their long awaited "air conditioned suit." Well, actually it's a vest at least, that will cool the wearer. The U.S. Army's "Microclimate Cooling System" is a vest full of tiny tubes that carry cooled water (with some non-toxic antifreeze added). Worn under the flak jacket, it keeps the trunk of the wearer cool, thus greatly reducing the "heat load" and potential for heat stroke or heat fatigue among troops who have to operate in very hot climates. The vest makes it possible for such troops to stay alert for nearly six hours, versus less than two hours without the vests. The system was first developed for pilots in smaller (un-air-conditioned) helicopters or door gunners of larger choppers. But the army is now sending 500 of the vests for use by troops operating in hummers, which are often not air conditioned. Troops who stand and man the turret machine-gun many hummers are equipped with, is particularly in need of the vest.
Helicopter crews, especially the crew chiefs who man a machine-gun mounted on an open door, have always had a problem with the weather. Few military helicopters have air conditioning, even for the pilots, and the crew chief on the UH-60 Blackhawk has to stay on his feet, and alert, for up to three hours at a time. In tropical areas, be they Vietnam four decades ago, or Iraq today, that can be a real chore. The crew chief wears a fire-resistant jumpsuit, flak jacket and helmet. Flying low to the ground, the heat is often over 100 degrees. Often there's not much breeze, for the chopper frequently hovers or moves slowly (under fifty kilometers an hour.) So the crew chief has to fight the heat while staying alert to any potential threats below. When the helicopter lands, the crew chief has to help with loading or unloading personnel or cargo, and maybe run around the chopper to check for any damage.
The cooling vest can only be used in vehicles, because the entire unit consists of the vest, a 13 pound cooling unit and an umbilical cord that attached to the vest. The cooling unit is plugged into the vehicles electrical system. The vests cost about $7,000 each and the army plans to equip the crews of over 9,000 helicopters with the vests by 2010. The army had originally planned to issue the vest to troops in 2004, but problems making the system reliable enough for troop use delayed things. The best was tested in Iraq two years ago, and that's where the reliability problems were discovered. The army also has a similar cooling system, for foot troops, in development. This 17 pound system is carried on the back, and an internal combustion engine supplies the power for the vest. About six ounces of fuel will keep the vest going for about five hours.
