Replacement Air Group

A Fleet Replacement Squadron (FRS), is a unit of the United States Navy and Marine Corps that trains Naval Aviators, Naval Flight Officers (NFOs) and enlisted Naval Aircrewman on the specific front-line aircraft they have been assigned to fly. Students, referred to as Replacement Pilots or Replacement Weapon Systems Officers are either newly winged aviators (Category I), aviators transitioning from one type aircraft to another (Category II), or aviators returning to the cockpit after a period of non-flying (Category III). After completing the training regimen, graduates are assigned to fleet squadrons. Additionally, FRSs are responsible for training aircraft mechanics, providing replacement aircraft for fleet squadron attrition, and standardizing maintenance and aircraft operations.

U.S. Navy and Marine personnel (RPs, instructors, maintainers, etc.) are frequently assigned to other services' FRSs. The FRSs were formerly known as Replacement Air Groups, and are thus commonly called "Rags".

From 1958 to 1971 the Navy organized the Fleet Replacement Squadrons for Carrier Based aircraft into Readiness Carrier Air Groups (RCVG) and Readiness Carrier Air Anti-Submarine Groups (RCVSG). On 20 December 1963 when all Carrier Air Groups were redesignated Carrier Air Wings (CVW) the RCVGs were redesignated Readiness Carrier Air Wings (RCVW), the RCVSGs however were not redesignated and they remained Readiness Carrier Air Anti-Submarine Groups until they were disestablished in 1970 and 1971. After disestablishment of the RCVWs and RCVSGs the Fleet Replacement Squadrons were placed under the operational control of the aircraft specific type or functional wings but they all retained their former RCVW or RCVSG tail codes.

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