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DOD Space Systems: Additional Knowledge Would Better Support Decisions about Disaggregating Large Satellites

GAO-15-7 Published: Oct 30, 2014. Publicly Released: Oct 30, 2014.
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What GAO Found

It is not yet known whether and to what degree disaggregation can help the Department of Defense (DOD) reduce acquisition costs and increase the resilience of its satellite systems. Experts GAO spoke with identified an array of benefits and limitations. For example, acquiring smaller, less complex satellites may require less time and effort to develop and produce. On the other hand, a larger number of satellites may be needed to provide the same level of capability, and the transition from existing system designs could increase costs. Experts agree that decisionmaking would benefit from assessments that look beyond a single satellite program and consider the broad range of potential effects of disaggregation. Benefits and limitations aside, there are longstanding barriers to implementation. For instance, disaggregation could exacerbate delays in the delivery of user equipment and ground systems. As GAO has reported, such delays, tied to management and oversight shortcomings, have resulted in expensive satellites being in orbit for years with limited use.

Notional Example of a Disaggregated Satellite System

Notional Example of a Disaggregated Satellite System

Note: For purposes of this graphic, strategic capabilities may refer to those needed for major operations, such as those involving nuclear weapons. Tactical capabilities may refer to those needed for more localized operations.

DOD is examining whether disaggregation should be used for some of its space systems, but significant uncertainty—including how to quantify a broad range of potential effects—remains. For example, DOD has initiated and completed studies and demonstrations, including Analyses of Alternatives that examine disaggregated concepts for certain systems. These studies can provide initial insights, such as rough order of magnitude costs of selected disaggregated scenarios, but they are not intended to comprehensively assess the effects of disaggregation. Moreover, DOD does not have common measures for resilience—a key space system consideration—which may limit the effectiveness of these assessments. Additionally, while technology demonstrations are providing an avenue for gaining knowledge about disaggregation, they have been limited, concentrating more on technical than operational feasibility. Focusing more on operational feasibility would help to empirically quantify the effects of disaggregation and address implementation barriers. Until more knowledge is gained, disaggregation will not only remain inconclusive, but poorly informed decisions could be made in the interim.

Why GAO Did This Study

Fiscal constraints and growing threats to space systems have led DOD to consider alternatives for acquiring space-based capabilities, including disaggregating large satellites into multiple, smaller satellites or payloads (see graphic). A Senate Armed Services Committee report mandated GAO to assess the potential benefits and drawbacks of disaggregation and examine if it offers decreased costs and increased survivability for selected DOD satellite systems.

This report (1) describes potential benefits and limitations of disaggregation, and (2) assesses the extent to which DOD is ready to make informed decisions regarding disaggregating these systems. GAO reviewed documents and interviewed officials from over 35 offices within DOD, civilian agencies, contractors, and third parties to compile a list of factors relating to potential impacts of disaggregation. GAO used these factors, along with prior GAO work on best practices and space acquisitions, as criteria for evaluating DOD's work to date on assessing disaggregation.


Before making decisions to disaggregate DOD space systems, DOD should (1) comprehensively examine the full range of potential effects of disaggregation, (2) develop common measures for resilience, and (3) expand demonstration efforts to examine the operational feasibility of disaggregation. DOD concurred with the first two recommendations and partially concurred with the third. GAO continues to believe DOD should demonstrate the operational feasibility of disaggregation.

Recommendations for Executive Action

Agency Affected Recommendation Status
Department of Defense Before making decisions on whether to disaggregate DOD's protected satellite communications, Space Based Infrared System (SBIRS), or environmental monitoring satellite systems, the Secretary of Defense should direct the Under Secretary of Defense for Acquisition, Technology and Logistics to comprehensively examine--either through the Analysis of Alternatives studies or through other assessments--the full range of disaggregation issues, including those that go beyond the satellite systems themselves.
Closed – Implemented
DOD has comprehensively examined disaggregating large satellites by completing analyses of alternatives (AOA) and related studies for individual satellite programs that included cost, capability, and risk analyses for aggregated and disaggregated alternatives. Specifically, DOD completed an AOA for the Space Based Infrared System (SBIRS) Follow-on in July 2015 and an AOA for Protected Satellite Communications Services (PSCS) in February 2016, both of which assessed disaggregation for satellite and ground systems. DOD conducted subsequent studies on resiliency in these areas in 2016, which informed resilience requirements for the SBIRS Follow-on (now called the Next-Generation Overhead Persistent Infrared Space program) and evaluated the benefits of resiliency in future architectures for the satellite communications mission. In addition, in December 2017, the department reported to Congress on the resilience and mission assurance of alternatives to SBIRS and the Advanced Extremely High Frequency system. The AOA for the SBEM area, which DOD issued in October 2013, evaluated options for satellite systems but did not analyze alternative ground segment components. However, DOD stated that it currently leverages a disaggregated ground system to support the SBEM mission area, and that it continues to examine supporting architectures for the planned solution, the Weather System Follow-on (WSF) program, through acquisition activities and efforts related to an enterprise ground system. DOD awarded a contract for the design of WSF in November 2017. By comprehensively assessing disaggregation issues, DOD was better positioned to make knowledge-based decisions for its follow-on space acquisitions.
Department of Defense Before making decisions on whether to disaggregate DOD's protected satellite communications, SBIRS, or environmental monitoring satellite systems, the Secretary of Defense should direct the Under Secretary of Defense for Acquisition, Technology and Logistics to develop common measures for resilience.
Closed – Implemented
DOD concurred with our recommendation. In November 2016, DOD established a space mission assurance framework, which includes resilience, and defined resilience in a department directive. The framework consists of three tiers based on the type of operation a system must be able to support during certain levels of conflict, and is intended to guide program definition and requirements development efforts. In August, 2018, DOD updated its requirements development manual to include this framework, and in July 2019, the Joint Requirements Oversight Council (JROC) validated the tiered approach. DOD implemented this framework for the first time by documenting resilience requirements for space vehicles in the Next Generation Overhead Persistent Infrared system, which the JROC validated in May 2019. By establishing this framework and using it to guide requirements development, DOD now has a more consistent method for measuring resilience across space systems and informing decisions about the level of resilience needed.
Department of Defense Before making decisions on whether to disaggregate DOD's protected satellite communications, SBIRS, or environmental monitoring satellite systems, the Secretary of Defense should direct the Under Secretary of Defense for Acquisition, Technology and Logistics to expand demonstration efforts to examine the operational feasibility of disaggregation by empirically quantifying its benefits and limitations as well as addressing longstanding barriers that could hinder its implementation.
Closed – Implemented
DOD partially concurred with our recommendation. The department said it agreed disaggregation requires continued detailed analysis and mission-specific assessment as one method to increase resiliency, but that the challenges of disaggregated ground systems are well-known to the department and it is well-versed in managing constellations with many satellites. As of August 2019, DOD has made progress toward examining the operational feasibility of disaggregation through plans for multiple demonstrations of disaggregated concepts. Specifically, DOD plans to launch a Space Based Infrared System demonstration satellite in fiscal year 2020 that will produce empirical flight data to inform migration to a disaggregated space architecture for missile warning capabilities. In addition, DOD is planning or has conducted several disaggregation proof-of-concept demonstrations for satellite communications capabilities from fiscal years 2018 through 2025. For example, according to an Office of the Secretary of Defense official, in August 2019, DOD observed successful over-the-air demonstration via Wideband Global Satellite Communications using Navy Multi-Band Terminal, as well as a completed demonstration using Air Force Ground Mobile Terminals. In total. completing these demonstrations may assist DOD in empirically quantifying the benefits and limitations of disaggregation and addressing potential barriers to its implementation.

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