Marine Corps Air Station Yuma or MCAS Yuma is a United States Marine Corps air station in Arizona. It is the home of multiple squadrons of F-35B Lightning IIs of the 3rd Marine Aircraft Wing, Marine Aviation Weapons and Tactics Squadron 1 (MAWTS-1), Marine Operational Test and Evaluation Squadron 1 (VMX-1) and Marine Fighter Training Squadron 401 (VMFT-401), an air combat adversary squadron of the 4th Marine Aircraft Wing of the Marine Corps Reserve. It is a designated Superfund site due to a number of soil and groundwater contaminants, including asbestos.

Marine Fighter Training Squadron 401 (VMFT-401) is an adversary squadron of the United States Marine Corps Reserve, flying the F-5N Tiger II. Known as the "Snipers", the squadron is the only adversary squadron in the Marine Corps, also is the first and only reserve squadron in the Marine Corps tasked to act as the opposing force in simulated air combat. They are based at Marine Corps Air Station Yuma and fall under the command of the 4th Marine Aircraft Wing and Marine Aircraft Group 41. VMFT-401 is a non-deployable unit.