IQUIQUE, Chile -- Airman 1st Class Larry Trejos (left) and Argentinean air force Master Sgt. Omar Daniel Grosso help Chilean air force Tech. Sgt. Juana Rivas properly adjust an oxygen mask Oct. 1 at Los Condores Air Base here. The Airmen are participating in Salitre 2004, a two-week multinational air combat training exercise among Chile, Argentina, Brazil and the United States. More than 100 U.S. active-duty and Air National Guard Airmen are participating in the exercise. Airman Trejos is assigned to the 28th Civil Engineer Squadron at Ellsworth Air Force Base, S.D. (U.S. Air Force photo by Staff Sgt. Matthew Lohr)