The Government Accountability Office (GAO) examined a Defense Department report to congressional defense committees on homeland missile defense and flight tests, but finds it provides limited help for Congress to make decisions. 

The Missile Defense Agency (MDA) is developing the Ground-based Midcourse Defense (GMD) system for homeland ballistic missile defense against a limited intermediate and ICBM attack from potential adversaries such as North Korea and Iran. Boeing [BA] leads an industry team on the program.

“Without an understanding of the effectiveness of MDA’s recent actions and plans related to GMD, Congress may not have the information it needs when making difficult choices on where to spend limited funds,” the nine-page report,

GAO-14-626R said.

For example, GAO said the DoD report noted MDA upgraded the software of the entire GMD interceptor fleet to improve their operational performance, “but it did not describe the effectiveness of these improvements or whether these improvements have been confirmed to work as intended in flight tests.”

Additionally, certain GMD improvement efforts DoD describes are high risk because they include concurrent manufacturing and testing, “which puts DoD at risk for cost growth, schedule delays, and performance shortfalls if it discovers problems after MDA begins manufacturing the interceptors,” the report said.

In 2009, GAO stated, it recommended MDA reduce concurrent manufacturing and testing.

“While DoD partially concurred with this recommendation, we concluded that it has not yet been fully implemented,” authors said.

The report also said DoD did not explain that a key flight test had been delayed nor offered reasons for that delay. DoD couldn’t provide results of one flight test, as it had not been conducted, due to efforts to resolve the previous flight test.

While the GAO report was at DoD for comment, MDA conducted the test on June 22. Initial test reports indicate the interceptor hit the target and analysis is ongoing.

“DoD’s report did not include an explanation of these development challenges, which limits the report’s usefulness because it provides no explanation to Congress on the issues that have delayed the flight test,” the report said.

The fiscal year 2013 National Defense Authorization Act directed DoD to submit a report on the status of efforts to improve the homeland ballistic missile defense and describe the results of two planned flight tests. The Act also required GAO to brief the four congressional defense committees on its views of the report.