WASHINGTON — U.S. Space Force plans to deploy five missile-warning satellites by 2029 so far is progressing on schedule but the service might be underestimating risks in the program, the Government Accountability Office says in a new report.

The program known as Next-Generation Overhead Persistent Infrared Block 0, or Next-Gen OPIR, was started by the U.S. Air Force in 2018 to supplement existing missile defense satellites. The Air Force compressed the program schedule by 42 months and plans to launch the first satellite by 2025. Next-Gen OPIR is now managed by the U.S. Space Force.

GAO in its annual assessment of DoD acquisition programs says Next-Gen OPIR “faces multiple challenges.” The report identifies two main issues. One is that a $2 billion ground system being developed for Next-Gen OPIR might not be ready when the first satellite goes to orbit. Another concern is that the integration of the sensors with the spacecraft will be more complex than anticipated.

In the annual report released June 3, GAO included “rapid prototyping and rapid fielding programs” in response to a provision in the National Defense Authorization Act for Fiscal Year 2019. The Next-Gen OPIR Block 0 falls in that category of “rapid prototyping” programs.

The constellation consists of three geosynchronous Earth orbit (GEO) satellites made by Lockheed Martin and two polar coverage highly elliptical orbit satellites made by Northrop Grumman.

GAO says one of the risks in Next-Gen OPIR is that the ground system “may not be ready when the first GEO satellite is delivered.” The Air Force in late 2019 selected Raytheon to develop an open-architecture operating system for future Next-Gen OPIR ground stations but a contract has not yet been awarded.

To ensure a ground system is available for the first launch, the program is designing GEO satellites to integrate into the ground architecture of existing Space Based Infrared System satellites but GAO says that will require “some modifications.”

The estimated $11 billion Next-Gen OPIR system is being built with existing satellite buses and sensor technology to reduce the risk, GAO says, but the program could run into difficulties in the integration phase. “While the program considers the spacecraft a mature legacy technology, the spacecraft will be modified to meet new mission requirements,” says the report. “DoD officials acknowledged the added risk presented by the first-time integration of a new sensor design with a modified spacecraft.”

Next-Gen OPIR is scheduled for a “critical design review” in November 2021. According to the report, Space Force officials told GAO that the program “is leveraging existing technology to mitigate multiple risks.”

Sandra Erwin writes about military space programs, policy, technology and the industry that supports this sector. She has covered the military, the Pentagon, Congress and the defense industry for nearly two decades as editor of NDIA’s National Defense...