Northrop Grumman said on Nov. 10 it recently finished the Critical Design Review (CDR) of the Hypersonic and Ballistic Tracking Space Sensor (HBTSS) prototype for the U.S. Missile Defense Agency (MDA).

The CDR establishes the company’s technical approach to the new sensor coverage that aims to help detect and defeat ballistic and hypersonic missiles from space. A CDR generally confirms a system design is stable and expected to meet performance requirements, on track to meet affordability and cost goals and establishes the initial product baseline. 

The company said the HBTSS satellites will provide continuous tracking and handoff to allow targeting of enemy missiles as part of the Overhead Persistent Infrared (OPIR) multi-layered constellation of satellites. OPIR satellites can sense heat signatures to detect and track missiles from launch to interception.

Northrop Grumman said the HBTSS satellites are also designed to track threats when prompted by other OPIR systems before the threats are in view of U.S. ground-based defenses.

“This critical design review puts Northrop Grumman on track to deliver a vital component of our missile defense architecture to keep the U.S. and its allies safe against hypersonic threats,” Sarah Willoughby, vice president for OPIR and geospatial systems at Northrop Grumman, said in a statement.

In January, MDA awarded Northrop Grumman a $155 million contract for the second prototype award in the HBTSS Phase IIA effort, which will have the company provide an HBTSS on-orbit prototype demonstration including launch and early orbit testing. The prototype is due to be delivered in 2023 (Defense Daily, Jan. 22).

Northrop Grumman said after the HBTSS prototype is delivered it will conduct an on-orbit test “to demonstrate its ability to continuously track and rapidly process its observations of hypersonic threats, as well as its ability to effectively hand off the information so the missile is intercepted.”

Northrop Grumman is one of two companies down-selected under the HBTSS program, after L3Harris Technologies [LHX] won a similar $122 million prototype contract in January as well (Defense Daily, Jan. 15).

Originally, in 2019, Northrop Grumman and L3Harris were joined by Leidos [LDOS] and Raytheon Technologies [RTX] as winning finalists of $20 million prototype awards to provide MDA with prototype payload designs and signal-chain processing risk reduction demonstration work (Defense Daily, Nov. 1, 2019).