What jobs were in the Vietnam War?

As in almost ALL US wars, the US military contracted with civilians to go over seas and do work. During WWII when US Wake Island was captured by Imperial Marines (Japanese) in 1942, some of the US Prisoners Of War (POW's) were US civilians employed by the US Government. In the United States during and after the US Civil War 1861-1865, civilian contractors were hired by the US Government to drive wagons and haul supplies to and from Army Forts. During the Vietnam War, US civilians did some work for the US Government with Intelligence Agencies; civilian contracting for building construction and other engineering efforts. Some medical operations, as well as airline companies were heavily contracted, such as Tiger and Braniff Air Lines.