Revolutionizing Missile Warning: The Proliferated Warfighter Space Architecture

Connected Satellite Network over Earth

How the SDA is Leveraging Commercial Practices to Modernize Missile Defense

In response to rapidly evolving threats from near-peer adversaries like Russia and China, the Space Development Agency (SDA) has successfully launched two rounds of its Tranche 0 satellites for its Proliferated Warfighter Space Architecture (PWSA). Despite delays, the SDA began fielding satellites from “order to orbit” in under 30 months – a marked improvement over traditional satellite procurement timelines for the Department of Defense (DOD). While Tranche 0 is intended to demonstrate basic program feasibility, their successful launches to date illustrate the DOD’s intention to leverage commercial practices to establish strategic deterrence in space.

“Space wasn’t always a contested environment like it is now,” said Mike Dickey, founding partner of Elara Nova: The Space Consultancy. “We could just load tons of capability and launch it to the place that was most efficient.”

The Traditional Missile Warning Approach

Missile warning architecture development began during the Cold War, when the Soviet Union was the sole adversary in space. With nuclear deterrence in mind, the DOD initiated programs such as the Missile Defense Alarm System (MIDAS) and the Defense Support Program (DSP), the latter of which evolved into the Space-Based Infrared System (SBIRS) program in place today. These legacy programs prioritized placing satellites at geosynchronous orbit (GEO) – over 22,000 miles above the Earth – to detect heat from ballistic missile launches.

“Geosynchronous orbit is this unique orbit where the orbit period exactly matches a day on the Earth,” said Dickey, who served as Chief Architect of the US Space Force and supported the stand-up of the Space Warfighting Analysis Center. “When you have one missile warning satellite parked over one area, then you get access to that area all the time and only one satellite is needed. But while that’s cost-efficient, it’s not militarily effective.”

Dickey likens the traditional approach to missile warning to that of a quarterback pass in football. The instant the ball leaves the quarterback’s hand, its trajectory is already determined and the receiver can run to where the ball will impact. However, this is no longer the case.

“Russia and China are building hypersonic, maneuvering missiles and so the trajectory is no longer predictable. You have to keep your eyes on it the entire time it’s flying, something we call ‘track custody,’” Dickey said. “Hypersonic missiles stay in the atmosphere and fly much closer to Earth, making it harder to detect from geosynchronous orbit. This caused the DOD to rethink its missile warning architecture and that helped give rise to the Space Development Agency and the Proliferated Warfighter Space Architecture.”

The SDA was founded in March 2019 to disrupt the DOD’s acquisition process in delivering space-based capabilities for the joint warfighter. Under the original name of the National Defense Space Architecture (NDSA), the SDA implemented one element of a new missile warning approach to include satellites at low Earth orbit (LEO) – an altitude just 1,200 miles or less from the Earth’s surface. Then in early 2023, the NDSA was re-named the Proliferated Warfighter Space Architecture (PWSA) to better demonstrate its relevance to the joint warfighter.

“There are two hypotheses that underpin PWSA,” Dickey said. “The first is that there is value in coming closer to the Earth. Dim objects become easier to see and the satellite can be simpler and less expensive. Furthermore, global coverage from low Earth orbit requires more satellites since less of the planet is in view at any one time. This ‘proliferation’ adds a measure of resilience to what traditionally had been a very fragile architecture.”

“The second hypothesis is that we can stay ahead of threats and in sync with technology through spiral development.”

Tracking and Data Transport for the Joint Fight

The first hypothesis – moving closer to the Earth – is demonstrated through what the SDA categorizes as the PWSA’s seven “layers,” or functions. The two primary layers of the architecture, Tracking and Transport, will operate together as an interconnected constellation of satellites in low Earth orbit. Tracking Layer satellites will detect and maintain custody of ballistic missile threats, while communicating their trajectory to the warfighter through a network of Transport Layer satellites in real-time.

This approach provides a solution for what Dickey reveals as another challenge of operating in low Earth orbit – access to ground stations that can receive and process data from space-based assets and distribute it to the warfighter. Through the Transport Layer satellites, the warfighter can monitor and defend against missile threats across vast areas, even those where ground stations aren’t immediately in view of the satellite that is seeing a threat missile.

“For example, the INDOPACOM theater stretches across the huge expanse of the Pacific Ocean where it’s difficult to keep the joint force connected and synchronized,” Dickey said. “So when a satellite is flying over that theater, where we don’t have many ground stations, that data has to be routed to the warfighter through other means.”

Successful deployment of PWSA is critical, as the architecture is widely viewed as the future “communications backbone” of JADC2 – the Joint All Domain Command and Control designed to integrate operations across the DOD’s military branches.

“We have to build a network where the warfighter can get the information they need to understand the next move in the joint fight,” Dickey said. “This space network is always in motion so it becomes complex to orchestrate, and this stepwise approach through tranches ensures all those complexities are addressed.”

Innovation Through Spiral Development

For the second hypothesis, PWSA is intending to keep pace with rapidly evolving technologies by developing its architecture through a series of “tranches,” or iterations that add further capability with each generation deployed every two years. This strategy embodies the ‘spiral development’ concept, where the DOD can continually refresh capabilities with the latest technology at a speed and scale similar to that of Apple’s newly-released iPhone 15.

“We had an iPhone 1 through 14 and bit by bit, its capabilities grew over time,” Dickey said. “In the traditional model, we only launched missile warning satellites every 15-20 years and so you couldn’t refresh their technology. PWSA allows us to refresh technology every two years, replicating the spiral development of the iPhone to get better and better with each tranche.”

Proliferated Warfighter Space Architecture

Tranche 0Warfighter immersion: The minimum viable product is demonstrating the feasibility of the proliferated architecture in cost, schedule and scalability towards necessary performance for beyond line of sight targeting and advanced missile detection and tracking.
Tranche 1Initial warfighting capability: Regional persistence for tactical data links, advanced missile detection, and beyond line of sight targeting.
Tranche 2Global persistence for all in Tranche 1. This will incorporate lessons learned from operating Tranche 0 for at least two years.
Tranche 3Advanced improvements over Tranche 2. This includes better sensitivity for missile tracking, better targeting capabilities for BLOS, additional PNT capabilities, advances in blue/green lasercom and protected RF comm.
Tranche 4Continual advances to the layers, including additional capabilities identified as current or future threats to the warfighter.
Source: Space Development Agency

The PWSA Tranches in Development

The first Tranche 0 launch in April of 2023 fielded eight Transport Layer satellites manufactured by York Space Systems and two SpaceX Tracking Layer satellites. The second, early September launch of Tranche 0 satellites included 11 Transport Layer satellites built by Lockheed Martin, an additional York Transport satellite and two more SpaceX Tracking satellites. A third and final launch for Tranche 0 is slated for later this year, when four L3Harris Tracking satellites will be deployed.

Tranche 0

York Space Systems10TransportApril 2023 (8); September 2023 (1);
Grounded as Testbed (1)
Lockheed Martin11TransportSeptember 2023
SpaceX4TrackingApril 2023 (2); September 2023 (2)
*as of September 2023

But the SDA is already looking ahead. The building phase of its Tranche 1 satellites is underway, with launches projected for late 2024. SDA is expecting to field 126 Transport Layer satellites in Tranche 1, with York Space Systems, Lockheed Martin and Northrop Grumman contracted to produce 42 each. For its Tracking Layer, 35 satellites are projected to be launched by 2025: 14 each by L3Harris and Northrop Grumman, with an additional seven from RTX Corporation (formerly known as Raytheon). An additional set of 18 experimental satellites will also be a part of Tranche 1, rounding its current projection of nearly 200 satellites.

Tranche 1

York Space Systems42TransportSeptember 2024
Lockheed Martin42TransportSeptember 2024
Northrop Grumman42TransportSeptember 2024
Northrop Grumman14TrackingApril 2025
L3Harris14TrackingApril 2025
Industry / Government18ExperimentalTBD
*as of September 2023

Leveraging Innovation Through Commercial Practices

Meanwhile, the SDA issued a solitication to industry for its Tranche 2 Tracking Layer satellites in early September. Just over 300 total satellites are projected to be fielded: 250 Transport satellites and 54 Tracking satellites. So far only Lockheed Martin and Northrop Grumman are under contract, slated to produce 36 satellites each for Tranche 2. However, as with the first two tranches, additional contractors are expected to contribute.

“Multiple contractors incentivizes continuous innovation and honest price points, because everybody wants to one-up their competitor when another contract is coming every two years,” Dickey said. “A secondary advantage is any failure in one production line doesn’t affect the others, so you’ve got some built-in resiliency as well.”

Advantages exist for the participating companies too, in contracting for the PWSA program.

“The government is a pretty good customer,” Dickey said. “They pay on time, their credit is good and they have a demand for technology that’s beyond the commercial marketplace. If you’re a commercial company, having a revenue stream from government contracts is pretty good for your shareholders, too.”

For legacy partners and budding commercial space start-ups alike, Elara Nova’s roster of military and industry space professionals provides the expertise and experience necessary to meet the evolving missile warning needs of the DOD.

“Elara Nova brings to its government and industry clients deep understanding about national security space,” Dickey said. “In this particular case, the talent pool we bring are people who were there during the transition from a traditional but fragile missile warning architecture, to something more militarily effective that can deter and win against a peer adversary.”

While the successful Tranche 0 launches to date signify a strong start to developing the missile warning architecture of the future, the PWSA still has a long way to go before its joint fight capabilities can be realized. Moving forward, the SDA must continue to leverage commercial practices and innovation to ensure PWSA’s success.

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