Defense Acquisitions:

Opportunities Exist to Achieve Greater Commonality and Efficiencies among Unmanned Aircraft Systems

GAO-09-520: Published: Jul 30, 2009. Publicly Released: Jul 30, 2009.

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From 2008 through 2013, the Department of Defense (DOD) plans to invest over $16 billion to develop and procure additional unmanned aircraft systems. To more effectively leverage its acquisition resources, DOD recognizes that it must achieve greater commonality among the military services' unmanned aircraft programs. Doing so, however, requires certain trade-offs and complex budget, cost, and schedule interactions. GAO was asked to assess the progress of selected unmanned aircraft acquisition programs, examine the extent to which the services are collaborating and identifying commonality among those programs, and identify key factors impacting the effectiveness their collaboration. GAO analyzed cost, schedule, and performance data for eight unmanned aircraft systems--accounting for over 80 percent of DOD's total planned investment in unmanned aircraft systems from 2008 through 2013--and two payload programs.

While proving successful on the battlefield, DOD's unmanned aircraft acquisitions continue to incur cost and schedule growth. The cumulative development costs for the 10 programs GAO reviewed increased by over $3.3 billion (37 percent in 2009 dollars) from initial estimates--with nearly $2.7 billion attributed to the Air Force's Global Hawk program. While 3 of the 10 programs had little or no development cost growth and 1 had a cost reduction, 6 programs experienced significant growth ranging from 60 percent to 264 percent. These outcomes are largely the result of changes in program requirements and system designs. Procurement funding requirements have also increased for most programs, primarily because of increases in the number of aircraft being procured, changes in system requirements, and upgrades and retrofits to equip fielded systems with capabilities that had been deferred. Overall, procurement unit costs increased by 12 percent, with unit cost increases of 25 percent or more for 3 aircraft programs. Finally, several programs have experienced significant delays in achieving initial operating capability, ranging from 1 to nearly 4 years. Several of the tactical and theater-level unmanned aircraft acquisition programs GAO reviewed have identified areas of commonality to leverage resources and gain efficiencies. For example, the Marine Corps chose to procure the Army's Shadow system after it determined Shadow could meet its requirements, and was able to avoid the cost of initial system development and quickly deliver capability to the warfighter. Also, the Navy's Broad Area Maritime Surveillance system will use a modified Global Hawk airframe. However, other programs have missed opportunities to achieve commonality and efficiencies. The Army's Sky Warrior--which is a variant of the Air Force's Predator, is being developed by the same contractor, and will provide similar capabilities--was initiated as a separate development program in 2005. Sky Warrior development is now estimated to cost nearly $570 million. DOD officials continue to press for more commonality in the two programs, but the aircraft still have little in common. Although several unmanned aircraft programs have achieved airframe commonality, service-driven acquisition processes and ineffective collaboration are key factors that have inhibited commonality among subsystems, payloads, and ground control stations. For example, the Army chose to develop a new sensor payload for its Sky Warrior, despite the fact that the sensor currently used on the Air Force's Predator is comparable and manufactured by the same contractor. To support their respective requirements, the services also make resource allocation decisions independently. DOD officials have not quantified the potential costs or benefits of pursuing various alternatives, including common systems. To maximize acquisition resources and meet increased demand, Congress and DOD have increasingly pushed for more commonality among unmanned aircraft systems.

Recommendations for Executive Action

  1. Status: Closed - Not Implemented

    Comments: Since the issuance of our report in July 2009, DOD has not conducted a comprehensive analysis examining requirements for the entire unmanned aircraft system (UAS) portfolio or strategies for making the systems more common; however DOD has conducted several limited examinations and has made some progress in these areas. For example, according to DOD officials, the Air Force has established government-owned and government-operated depot maintenance repair capabilities and the Army is leveraging the Air Force's infrastructure for its own unmanned aircraft maintenance. The Air Force and Navy continue to look for ways to establish synergies in depot activities for the Global Hawk and Triton unmanned aircraft systems, including a shared obsolescence and parts management strategy for the two programs. DOD officials further stated that, in 2014, the Air Force evaluated common equipment and requirements for sense-and-avoid capabilities, including a system developed by the Army. The Air Force is in the process of installing this equipment at three locations. DOD has also conducted limited examinations of requirements, including a 2-year assessment of specific mission areas to determine if planned and current capabilities--including both manned and unmanned systems--are sufficient to achieve validated requirements, and a strategic portfolio review of its intelligence, surveillance, and reconnaissance force structure and capabilities, including space and airborne assets, which will be used to inform future studies. In addition, DOD has provided several reports to Congress related to coordination and commonality for UAS, including a 2013 report on overcoming challenges for UAS through cross-service coordination, and a 2014 report on DOD's use of common ground control station architecture. DOD is making progress in achieving commonality among ground control stations with its common ground control station architecture, including the development of an online repository of reusable services and applications available for download to suit individual UAS program needs. However, GAO work has found that DOD has not necessarily made progress in commonality among aircraft or payloads. We are closing this recommendation as not implemented because DOD has not undertaken a comprehensive analysis of its UAS programs, including the costs and benefits of alternative approaches and specific actions that need to be taken to make its UAS programs more common.

    Recommendation: To more effectively leverage resources and increase the efficiency in unmanned aircraft system acquisition programs, the Secretary of Defense should direct a rigorous and comprehensive analysis of the requirements for current unmanned aircraft programs, develop a strategy for making systems and subsystems among those programs more common, and report the findings of this analysis to Congress. At a minimum, this analysis should quantify the costs and benefits of alternative approaches, identify specific actions that need to be taken, and summarize the status of DOD's various ongoing unmanned aircraft-related studies.

    Agency Affected: Department of Defense

  2. Status: Closed - Implemented

    Comments: In 2011, DOD issued its Unmanned Systems Integrated Roadmap (FY2011-2036) that emphasized the need to establish a complementary relationship between manned and unmanned capabilities while optimizing commonality and interoperability across space, air, ground, and maritime domains. In addition, the Roadmap emphasized the need to leverage open architecture and open interfaces to help achieve modularity, commonality, and interchangeability across payloads, control systems, video/audio interfaces, data, and communications links. DOD acknowledges that this openness will enhance competition, lower life-cycle costs, and provide warfighters with enhanced unmanned capabilities that enable commonality and joint interoperability on the battlefield. In the case of the Unmanned Carrier Launched Airborne Surveillance and Strike (UCLASS) aircraft development program, the Navy has emphasized that it is taking an open architecture approach and pursuing subsystems that are common with other aircraft. In addition, the Navy is also pursuing a non-proprietary, scalable, open-architecture solution for unmanned air systems, known as the Common Control Station (CCS), that it believes will facilitate interoperability, usability, and commonality, and reduce development and sustainment costs. DOD's added emphasis on commonality, its stated plan to pursue open architecture and open interfaces in all areas of unmanned systems, along with the Navy's efforts to pursue commonality and open architecture in the UCLASS and CCS programs, meet the intent of our recommendation.

    Recommendation: To more effectively leverage resources and increase the efficiency in unmanned aircraft system acquisition programs, and prior to initiating any new unmanned aircraft program, the Secretary of Defense should require the military services to identify and document in their acquisition plans and strategies specific areas where commonality can be achieved, take an open systems approach to product development, conduct a quantitative analysis that examines the costs and benefits of various levels of commonality, and establish a collaborative approach and management framework to periodically assess and effectively manage commonality.

    Agency Affected: Department of Defense


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