Master Sgt. Ronald ‘Rocky’ Brovold, of the 119th Maintenance Squadron propulsion element, operates controls of an aircraft engine test facility, better known as the ‘hush house,’ at the North Dakota Air National Guard Base, Fargo, North Dakota, March 29, 2001. Brovold is doing a full throttle analysis of a Pratt and Whitney F-16 engine to verify performance. (U.S. Air National Guard Photo by Tech. Sgt. Bradly Schneider/Released)