Air Guard had been a reserve force for federal use only in wartime or national emergency. By the 1980s, the Air Guard was an integral part of daily Air Force operations in what was called "The Total Force Policy" of the United States Department of Defense (DoD). As a result, the Massachusetts Air Guard took on more missions. With the receipt of the A-10, the 131st began a commitment to USAFE, beginning frequent deployments to West Germany, England, Italy, Turkey, and other NATO bases. In 1990 the 131st was programmed to receive the specialized Block 10 F-16A/B Fighting Falcon, also referred to as the F/A-16 due to its close air support configuration. The 1990 Gulf Crisis, however, delayed this transition. During Operation Desert Storm, the F/A-16 was battle tested and it was discovered that the close air support F-16 project was a failure. Subsequently, the conversion of the squadron was cancelled in 1993, and the 131st remained an A-10 Thunderbolt II close air support squadron. Air Combat Command In March 1992, the unit was redesignated as the 131st Fighter Squadron. In June, Tactical Air Command was inactivated and was replaced by Air Combat Command (ACC). In 1995, the 104th adopted the Air Force Objective Organization plan and the 104th Fighter Group became a Wing, and the 131st was assigned to the new 104th Operations Group. From August to October 1995, some 400 Airmen of the 104th Fighter Wing deployed to Aviano Air Base, Italy as part of the NATO mission to repel Serbian forces in Bosnia. This was the first time that the 131st Fighter Squadron flew combat sorties since World War II. Four years later, in 1999, elements of the 104th mobilized and flew sorties over the skies of the former Republic of Yugoslavia. As part of an Air Guard A-10 group, the 131st attacked Serb forces in Kosovo. In mid-1996, the Air Force, in response to budget cuts, and changing world situations, began experimenting with Air Expeditionary organizations. The Air Expeditionary Force (AEF) concept was developed that would mix Active-Duty, Reserve and Air National Guard elements into a combined force, instead of entire permanent units deploying as in the 1991 Gulf War, Expeditionary units are composed of "aviation packages" from several wings, including active-duty Air Force, the Air Force Reserve Command and the Air National Guard, would be married together to carry out the assigned deployment rotation. As