The Fairchild C-123 Provider is an American military transport aircraft designed by Chase Aircraft and then built by Fairchild Aircraft for the U.S. Air Force. In addition to its USAF service, which included later service with the Air Force Reserve and the Air National Guard, it also went on to serve most notably with the U.S. Coast Guard and various air forces in Southeast Asia. During the War in Vietnam, the C-123 was used to deliver supplies, to evacuate the wounded, and also used to spray Agent Orange. he C-123 Provider was designed originally as an assault glider aircraft for the United States Air Force (USAF) by Chase Aircraft as the XCG-20 (Chase designation MS-8 Avitruc)[2] Two powered variants of the XCG-20 were developed during the early 1950s, as the XC-123 and XC-123A. The only difference between the two was the type of engines used. The XC-123 used two Pratt & Whitney R-2800-23 air-cooled radial piston engines, while the XC-123A was fitted with four General Electric J47-GE-11 turbojets, in two pods.[3]