The Air Force Can Reduce Its Stated Requirements for Strategic Airlift Crews

LCD-79-411: Published: Sep 19, 1979. Publicly Released: Sep 19, 1979.

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Maintaining more crews than necessary to fly the C-5 and C-141 strategic airlift planes is costly and unjustified. The Air Force has determined that it needs four crews for each of these aircraft, but due to efforts to preserve the service life of the C-5 by limiting the flying hours of the fleet, only 3.25 aircrews are presently authorized for each C-5. The Air Force has developed and uses a computer model simulating the operations of the strategic airlift system under wartime conditions to determine crew needs. However, a number of factors the Air Force uses are unrealistic and tend to overstate crew needs.

GAO analyzed model simulations made by the Air Force and noted that during the first 45 days of an emergency, the period of highest demand, the utilization rate attained with a crew ratio of 3 to 1, with no flying hour limits imposed, was comparable to the rate attained with a 4 to 1 crew ratio with flying hour limits imposed. Where no flying hour limits were imposed, certain aircrews exceeded the 125 hours within 30 days limit. This indicated that a reduced crew ratio warrants serious consideration. A reduction of the aircrew ratio on from the currently authorized 3.25:1 to 3:1 for the C-5, and from 4:1 to 3:1 for the C-141, would lower the Air Force's annual funding requirement by as much as $105 million for the strategic airlift operational fleet if only active duty personnel were reduced. The Air Force omitted the effects of aircraft attrition in estimating required crews. At least three extra crews become available when each plane is lost. The Air Force indicates the extent of fatigue varies among aircrew positions; does not consider ground times at home stations to perform aircraft maintenance in its latest model simulations; assumes that all required crewmembers are fully qualified, onboard, and available for flying duties; and assumes, in its computer model, that crews must perform staff duties as well as flying airlift missions.

Recommendation for Executive Action

  1. Status: Closed

    Comments: Please call 202/512-6100 for additional information.

    Recommendation: To improve the process of determining strategic airlift crew requirements and achieve more valid ratios, the Secretary of Defense should require the Secretary of the Air Force to: revise the airlift simulation model program to reflect a peacetime to wartime transition and achievable aircraft utilization rates which do not exceed those established by the Secretary of Defense; reassess the established flying hour limits for aircrews to determine the feasibility of increasing them, especially the 125-hour/30 day limit; include attrition rates for strategic airlift aircraft and assess the impact such attrition would have on the number of aircrews required; evaluate the feasibility of establishing different aircrew ratios for each crew position based upon differing fatigue rates for the various positions; reassess the need for airlift crews to perform staff duties during wartime to the detriment of flying operations; recognize, in aircrew requirements estimates, that all crews will not be fully qualified and available at any point in time; and include ground times at home stations in estimating the hours planes are available for flying.

    Agency Affected:


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