Airman Clint Hubkey, 28th Civil Engineer Squadron heating, ventilation and air conditioning journeyman, wraps a heating vent on a duct at Ellsworth Air Force Base, S.D., Jan. 26, 2011. The Air Force saved more than $75,000 by having the Airmen from 28th CES install the new HVAC system rather than contractors. (U.S. Air Force photo/Senior Airman Anthony Sanchelli)