GAO reviewed how the C-17 aircraft was used during the North Atlantic Treaty Organization (NATO) peacekeeping force deployment to Bosnia, focusing on: (1) how well it performed during the deployment; and (2) whether deployment transportation requirements included the need for airlift aircraft to perform any of the C-17's expected operational capabilities.

GAO found that: (1) during Operation Joint Endeavor, the C-17 accomplished the airlift tasks required of it, as did other airlifters such as the C-141, the C-5, and the C-130; (2) the C-17 was used to satisfy the Army's immediate need for a high-capacity, short distance air transport to move troops, equipment, and outsize cargo from central Europe into the Bosnia area of operations; (3) the C-17 performed about 26 percent of the deployment airlift missions and carried about 44 percent of the cargo moved during the deployment; (4) the C-17 also performed a limited number of strategic airlift missions in which it delivered cargo from the continental United States to final destinations in Germany, Hungary, and Bosnia; (5) according to contractor reports, the C-17 achieved a mission capable rate of 86.2 percent during the December 1995 through February 1996 time frame compared to a required rate of 81.2 percent; (6) transportation needs of the Bosnia deployment did not offer the opportunity for any airlift aircraft to perform or demonstrate several operational roles and missions; and (7) consequently, the C-17 was not required to perform many tasks which it had trouble doing, or did not do, during operational testing.