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Unmanned Carrier-Based Aircraft System: Debate over System's Role Led to Focus on Aerial Refueling

GAO-16-389R Published: Mar 24, 2016. Publicly Released: Mar 24, 2016.
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What GAO Found

In 2015, the Department of Defense (DOD) conducted a review of its airborne intelligence, surveillance, and reconnaissance portfolio and debated the primary role of the Navy Unmanned Carrier-Launched Airborne Surveillance and Strike (UCLASS) system. As a result, DOD restructured the UCLASS program in its fiscal year 2017 budget submission to create the Carrier Based Aerial Refueling System (CBARS) program. CBARS will be an unmanned system designed to conduct automated aerial refueling of other carrier-based aircraft, as well as provide some intelligence, surveillance, and reconnaissance capability. This represents a shift in the focus of the system’s mission. The Navy plans to invest more than $2 billion in the CBARS program from fiscal year 2017 through fiscal year 2021, as shown in the figure below.

Planned Investments in the Carrier Based Aerial Refueling System


Note: Then-year dollars include the effects of inflation and escalation.

As with UCLASS, the CBARS program will consist of three key segments: 

  • air system segment,
  • aircraft carrier segment, and
  • control system and connectivity segment. 

While requirements for the air system were being debated, the Navy continued to make progress on the other two segments, according to budget documents. For example, as part of the carrier segment, the Navy has begun to develop modifications to existing shipboard systems, including hardware for test and integration activities. Within the control system and connectivity segment, the Navy has started development of additional prototype control stations, including those required to support testing. The Navy plans to release a request for proposal for the aerial refueling air system early in fiscal year 2017, and to award an air system development contract early in fiscal year 2018. It expects to provide CBARS to the fleet by the mid-2020s. Although the general direction of the restructured program is outlined in the fiscal year 2017 budget submission, a more detailed acquisition strategy for this program has yet to be released. GAO will continue to monitor this strategy as more details become available.

Why GAO Did This Study

Prior to February 2016, the Navy had planned to invest over $3 billion through fiscal year 2022 in the development of the UCLASS system. GAO found in a May 2015 report (GAO-15-374) that the intended mission and required capabilities of UCLASS were under review as there was debate within DOD about whether the primary role of the UCLASS system should be largely surveillance with limited strike capability operating in less contested environments, or largely strike with limited surveillance capability operating in highly contested environments. This debate delayed the expected award of the air system development contract by about 3 years from 2014 to 2017. 

In its May 2015 report, GAO also found that knowledge the Navy had obtained from reviewing the UCLASS preliminary designs of four contractors might have limited applicability depending on the system’s final requirements. The preliminary designs were based on a more surveillance-centric set of requirements. GAO concluded that if the final UCLASS requirements emphasized a strike role with limited surveillance, the Navy would likely need to revisit the technologies and proposed designs for the system, as well as the amount of funding that would be needed for development. 

The National Defense Authorization Act for Fiscal Year 2014 included a provision that GAO review the status of the UCLASS acquisition program annually. This report describes changes to the UCLASS program since GAO’s May 2015 report. To do this work, GAO analyzed the President’s budget submission for DOD for fiscal year 2017, and spoke with program and other cognizant Navy officials.

For more information, contact Michael J. Sullivan at (202) 512-4841 or

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AccountabilityAir defense systemsAircraftAuditing standardsDefense acquisition programsInternal controlsInvestment planningMilitary aircraftMilitary forcesMilitary intelligenceMission budgetingSystems design