Military Aircraft:

DOD Needs to Determine Its Aerial Refueling Aircraft Requirements

GAO-04-349: Published: Jun 4, 2004. Publicly Released: Jun 4, 2004.

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William M. Solis
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With the heavy pace of operations in support of the war on terrorism, the Department of Defense (DOD) and the Air Force have become increasingly concerned about their aging aerial refueling aircraft. We last reviewed the aerial refueling fleet in 1996 and found that KC-135 aircraft were aging and becoming increasingly costly to maintain and operate. In December 2001, we began new work on the Air Force's requirements for refueling aircraft. However, we suspended our work several times to provide testimony and other products on the condition of the current fleet and Air Force plans to accelerate replacement. We were asked to review (1) the extent to which the current fleet has met aerial refueling needs, and the cost and effort to operate and sustain the fleet, (2) DOD's current refueling requirements, and (3) options to meet future aerial refueling needs.

The current refueling force has successfully supported the needs of U.S. combat and mobility air forces during peacetime and wartime operations but future support costs will continue to rise as the fleet continues to age, according to the Air Force. Congress authorized the Air Force to acquire 100 KC-767A aerial refueling aircraft in November 2003 as the first step in replacing the 538-plane KC-135 fleet but it could take up to 30 years to replace the rest based on the estimated production rate for the first 100 aircraft. Thus, the Air Force will need to continue maintaining and modernizing some of the remaining aircraft for up to 3 decades. Some of those aircraft could be 70 to 80 years old when they are eventually replaced. DOD does not know how many or what type of aircraft are needed to meet future refueling needs because its requirements study is out of date. The most recent study, Tanker Requirements Study-05, was done in 2001 and identified the number of aircraft needed to carry out a two-major-theaterwar strategy. However, that strategy has been superceded by a new capabilities-based approach contained in the 2001 Quadrennial Defense Review. In addition, significant changes taking place in operational concepts and force structure could substantially affect future refueling requirements. As a result, the Air Force does not have a clear picture of future needs that could guide its replacement and investment decisions. GAO outlines three broad options to meet the Air Force's long-term aerial refueling requirements. DOD could adopt one or a combination of these approaches. GAO is not taking a position on which option(s) would be most suitable. The Air Force was recently directed by DOD to conduct and complete by August 2005 an analysis of alternatives for replacing the current capability. However, at the time of our audit work, the Air Force did not plan to study the option of using contractor-provided aerial refueling services as part of its analysis of alternatives.

Recommendations for Executive Action

  1. Status: Closed - Not Implemented

    Comments: DOD completed a Mobility Capabilities Study in 2006. However, GAO had concerns about this study and urged decision makers to exercise caution when using the Study. This study did not address the tanker issue. MCS 2006, a follow-on study, may have a tanker component; however, that study is not complete. Nevertheless, DOD is currently evaluating proposals submitted for a new tanker and expects to award a contract by Jan. 2008 for the first planes, without further studies being done.

    Recommendation: To provide a current, comprehensive roadmap to guide long-term replacement of the current tanker fleet, the Secretary of Defense should conduct a new, validated requirements study to determine the current and projected aerial refueling requirements.

    Agency Affected: Department of Defense

  2. Status: Closed - Implemented

    Comments: DOD conducted an analysis of alternatives for the tanker replacement, but rejected the option of contractor-provided air refueling services to meet some portion of its needs.

    Recommendation: The Secretary of Defense should direct that the Air Force's planned analysis of alternatives be a comprehensive study of all reasonable options, including using contractor-provided aerial refueling services to meet some portion of its aerial refueling needs.

    Agency Affected: Department of Defense


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