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Missile Defense: Assessment of DOD's Reports on Status of Efforts and Options for Improving Homeland Missile Defense

GAO-16-254R Published: Feb 17, 2016. Publicly Released: Feb 17, 2016.
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What GAO Found

The Department of Defense’s (DOD) August 2015 and September 2015 homeland missile defense reports generally met most of the required reporting elements from section 238 of the National Defense Authorization Act for Fiscal Year 2014 (FY14 NDAA) and section 1665 of the National Defense Authorization Act for Fiscal Year 2015 (FY15 NDAA), such as including descriptions of: 

  • the current and future ballistic missile threat assessment;
  • current homeland ballistic missile defense capabilities; and
  • planned improvements to current homeland ballistic missile defense.

However, DOD’s reports generally did not meet the requirements to include an evaluation of options for improving homeland missile defense and were not submitted by the required deadlines. Rather than including in its reports the required evaluation of options, DOD referred the congressional defense committees to a separate, ongoing study being performed by the department to assess future homeland missile defense options and committed to providing them with results when the study is completed.

Although DOD’s reports described the benefits of the Missile Defense Agency’s (MDA) ongoing efforts to improve homeland missile defense, GAO found that MDA faces risks and challenges pursuing these efforts. For example, DOD’s reports stated that MDA has fielded additional homeland missile defense assets, including Ground-based Midcourse Defense (GMD) interceptors, and is capable of defending the U.S. homeland from a limited ballistic missile attack from North Korea or Iran. However, a 2015 assessment conducted by DOD’s Director, Operational Test and Evaluation determined that although GMD has demonstrated a partial capability against small numbers of simple ballistic missile threats launched from North Korea and Iran, GMD flight testing, to date, was insufficient to demonstrate that an operationally useful defense capability exists. DOD’s reports also described ongoing efforts to support the Secretary of Defense’s directive to increase the number of fielded GMD interceptors from 30 to 44 by the end of 2017 to add protection to the U.S. homeland. However, GAO found that in order to achieve this goal, MDA is relying on a highly optimistic and aggressive schedule that overlaps development and testing with production activities. In addition, DOD’s reports described the benefits associated with MDA’s plans to redesign the current GMD kill vehicle—the part of the interceptor that is released during flight to detect and destroy the threat. However, GAO found that MDA may encounter challenges with some aspects of the Redesigned Kill Vehicle’s (RKV) acquisition approach, such as contract strategy, industry collaboration efforts, and schedule. For example, MDA may be unable to deliver RKV interceptors within its committed time frames and cost parameters because it has not negotiated the terms of the modification with the GMD prime contractor.

In GAO’s prior work on missile defense, it made several recommendations aimed at assisting MDA in improving its acquisition outcomes and minimizing risk, such as implementing a knowledge-based acquisition strategy, including sufficient schedule and resource margin in it its test plan, and aligning production decisions with flight testing. MDA concurred with many of GAO’s recommendations and has taken some actions to address them but several of GAO’s recommendations have not been implemented. GAO continues to believe these recommendations are valid and should be fully implemented.

Why GAO Did This Study

Protection of the United States from the threat of ballistic missile attacks is a critical national security priority but, according to MDA, the current GMD kill vehicle represents a performance plateau that cannot be overcome without augmenting and replacing the kill vehicles in the current fleet of interceptors. DOD submitted reports on the status of efforts and options for improving homeland ballistic missile defense in response to requirements from the FY14 NDAA and FY15 NDAA. The joint explanatory statements for both the FY14 NDAA and FY15 NDDA included provisions for GAO to brief the congressional defense committees and the joint explanatory statement for the FY15 NDAA also included a provision for GAO to submit a report on its views of DOD’s reports as soon as practicable.

This report assesses (1) the extent to which DOD’s reports addressed the required reporting elements from the FY14 NDAA and FY15 NDAA and (2) the benefits and risks associated with the plans and efforts described in DOD’s reports. This report documents the findings GAO presented during its briefings with the congressional defense committees in October 2015. GAO reviewed DOD’s reports, compared information in DOD’s reports to GAO’s best practices for following a knowledge-based acquisition approach, reviewed MDA program management documents, and met with officials from MDA, U.S. Northern Command, and U.S. Strategic Command to corroborate key acquisition information.

For more information, contact Cristina Chaplain at (202) 512-4841 or

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Ballistic missile defenseBallistic missilesDefense acquisition programsDefense capabilitiesDefense economic analysisDefense procurementFederal procurementOperational testingReporting requirementsRisk managementSchedule slippagesStrategic planningSystems designWeapons systems