SDA to acquire satellites with custom payloads to enable faster targeting on battlefields

The Space Development Agency is gearing up for its next procurement of satellites for a military communications network known as the Transport Layer Tranche 2. SDA, an agency under the U.S. Space Force, plans to acquire 20 satellites carrying a new type of payload to transmit targeting information. SDA documents describe the payload, dubbed Warlock, as a communications node “specifically designed to close future kill chains.” Unlike other payloads acquired by SDA, which are commercially available, Warlock will have to be developed “for space systems to provide fire control solutions.” The description suggests the Gamma satellite program is pursuing advanced data-relay technologies to reduce sensor-to-shooter timelines, or the crucial flow of information in modern military operations, which requires real-time intelligence and rapid decision-making. The new procurement is called Transport Layer Tranche 2 Gamma. The agency on Jan. 10 announced it is holding a classified briefing for contractors next month in Chantilly, Virginia, to discuss details of the program. According to a draft solicitation, SDA intends to select one vendor to supply all 20 Tranche 2 Gamma satellites. A final request for proposals is expected to be released this spring.

 

Proliferated tactical network

The agency is building a large mesh network of military satellites in low Earth orbit known as the Proliferated Warfighter Space Architecture. The Transport Layer will serve as a tactical network to move data to users around the world.

SDA has already ordered 190 satellites for the portion of the architecture known as the Transport Layer Tranche 2 — 100 “Alpha” satellites to be manufactured by Northrop Grumman and York Space Systems, and 90 “Beta” satellites to be produced by Lockheed Martin, Northrop Grumman and Rocket Lab USA.

The agency said all Transport Layer satellites will have at least three optical laser links, Ka-band communications relays and other networking payloads. But only the 20 Gamma satellites will have four optical terminals and the Warlock payload.

SDA said it’s buying just 20 satellites carrying the Warlock payload to “demonstrate an operational capability for proliferation in future tranches.”

The Proliferated Warfighter Space Architecture is a web of hundreds of small satellites in low Earth orbit that promises secure, high-bandwidth communications for warfighters on the ground, transforming how they share information and coordinate strikes.

The payloads envisioned for the Gamma satellites point to a future where the U.S. military relies increasingly on space-based sensors rather than aircraft to identify and track targets in contested battle spaces. In scenarios where rival anti-aircraft threats inhibit the deployment of manned and unmanned aerial intelligence platforms, satellites would provide persistent overhead surveillance even in denied environments.

By networking space-based sensors through laser cross-links between the satellites, SDA plans to overcome traditional limitations getting data to where it needs to go, agency leaders have said. Technologies like Warlock would enable rapid transmission and handoff so military commanders on the ground can react quickly to emerging situations and adjust targeting plans as needed.

Space Development Agency awards Northrop Grumman $732 million contract for 38 satellites and support services

The Space Development Agency awarded Northrop Grumman a $732 million contract for 38 communications satellites that will be part of the U.S. military’s low Earth orbit space architecture, the company announced Oct. 30. These satellites are for the portion of SDA’s mesh network known as Transport Layer Tranche 2 Alpha that will have a total of 100 satellites. The agency selected York Space Systems to build the other 62 spacecraft. Northrop Grumman’s contract includes ground systems and five years of operations and sustainment. The agreement includes an incentive payment for on-time delivery. The Alpha satellites are projected to launch in late 2026. Northrop won order for Alpha and Beta satellites. SDA, an organization under the U.S. Space Force, is building a layered network of military satellites. The Transport Layer will serve as a tactical network to move data to users around the world, transmitting classified data such as early warnings of missile launches. Alpha satellites carry optical communications terminals, Ka-band communications and Link 16 data transmission payloads. Transport Layer Tranche 2 also includes 72 Beta satellites that SDA recently ordered from Lockheed Martin and Northrop Grumman. These carry more complex communications payloads.

Rendering of Space Development Agency's Transport Layer Tranche 2 Alpha satellites. Credit: Northrop Grumman

 

Northrop Grumman to date has won orders from SDA for 132 satellites for the Transport and the Tracking Layer. Both layers are designed to interoperate in space using a common data standard allowing satellites made by various manufacturers to communicate with one another.

Space Development Agency to launch 13 satellites in late June

The Space Development Agency is preparing to launch at least 13 satellites in late June, the agency’s director Derek Tournear said May 26. This will be SDA’s second launch of Tranche 0 satellites for its proliferated low Earth orbit constellation. Tranche 0 is a 28-satellite demonstration constellation. The first 10 spacecraft — eight communications satellites made by York Space and two missile-detection satellites made by SpaceX — launched April 2 on a SpaceX Falcon 9. SDA initially planned to launch all 18 remaining in June but made some late changes to the manifest, Tournear said in an interview with SpaceNews. The upcoming mission — scheduled to fly on a SpaceX Falcon 9 rocket in late June from Vandenberg Space Force Base, California — is now projected to launch 11 communications satellites (10 made by Lockheed Martin and one made by York Space) and two missile-tracking satellites made by SpaceX. There were two Tranche 0 York satellites on the manifest but one is likely to be kept on the ground so SDA can use it for software tests, said Tournear. Four L3Harris Tranche 0 satellites were scheduled to launch but were taken off the manifest due to production delays, he said. The four satellites will fly to orbit on a separate mission planned by the Missile Defense Agency. MDA is preparing to launch two prototypes — one made by L3Harris and the other by Northrop Grumman — for its Hypersonic and Ballistic Tracking Space Sensor (HBTSS). SDA and MDA are collaborating closely on missile tracking and missile defense architectures, said Tournear. The agencies agreed to deploy L3Harris’ wide field-of-view satellites made for SDA in the same orbit as the HBTSS medium field-of-view missile defense satellites.

This will help both agencies figure out how they will integrate future sensor networks, said Tournear.

The new plan turned out to be a “win win,” he said. “Once MDA agreed that we could put our L3Harris satellites on their launch, it became a very easy choice.”

MDA has not yet announced a launch date for the HBTSS mission.

SDA’s first 10 satellites in good health

Of the 10 satellites launched April 2, both SpaceX tracking satellites have reached the intended orbit about 1,000 kilometers above Earth.

“We will be able to get tracking data very shortly,” said Tournear. “We have to make sure we have the payloads and the software in place to be able to do the tracking mission.”

The eight York satellites haven’t performed their orbit raising yet because SDA needs extra time to test the Link 16 payloads onboard those satellites, he said.

Link 16 is a data exchange and radio communications network widely used by the U.S. military and NATO allies.

Once the York satellites complete their orbit raising, SDA will test the inter-satellite laser communications links, which requires more separation between the satellites.

“Our plan is to have everything tested, checked out and ready to do initial mission demonstrations in late June. early July,” said Tournear.

The Tranche 0 satellites are what SDA calls a “warfighter immersion tranche” that will give military users an opportunity to experiment with the technology and better understand the capabilities of LEO satellites for missile tracking and for data relay.

Following the Tranche 0 deployment, SDA plans to launch dozens more satellites on a monthly cadence starting with Tranche 1 in late 2024.

The Tracking Layer is envisioned as a global network of sensors that will provide a defense shield against Russian and Chinese ballistic and hypersonic missiles. The data collected by missile-tracking satellites will be sent via optical links to the Transport Layer. That would ensure that if a missile threat is detected, its location and trajectory data can be transmitted securely through space and downlinked to military command centers.

SpaceX’s final Tracking Layer satellites

Tournear said the four tracking satellites made by SpaceX for Tranche 0 are likely to be the company’s last. SpaceX did not bid for the Tracking Layer Tranche 1 contract, which was won by L3Harris and Northrop Grumman.

To meet SDA’s required satellite orbit at 1,000 kilometers, SpaceX built the four satellites using a customized bus, not the one the company mass-produces for its Starlink internet constellation, Tournear said.

To track hypersonic missiles in all phases of flight, DoD determined that satellites 1,000 kilometers above Earth will be better positioned to see these targets.

SpaceX informed SDA it did not bid for Tranche 1 because the requirements could not be met with the Starlink bus, said Tournear, However, “we’re working with them to see how they can participate in the future.”

SDA is seeking input from LEO internet companies like SpaceX, Amazon and others on how they might provide a low-Earth orbit “backhaul” capability to support military data transport.

“We are looking for how commercial providers could augment the overall Defense Department space data transport layer and have a seamless integration with the SDA data transport layer,” said Tournear. “So there’s certainly activities like that that are going on.”

SDA’s vision is to deploy “translator satellites” that would allow SDA spacecraft to talk to commercial remote-sensing and communications providers.

“We are looking for ideas from companies on how they could tie their company’s offerings into the transport layer,” he said, “so that we can have multiple different pathways to get low latency, tactical data link, and also be able to augment or back that up with commercial systems.”

Space Development Agency issues draft solicitation for 100 satellites

The Space Development Agency is planning a new procurement of 100 satellites to continue to build out a military constellation in low Earth orbit. In a May 11 draft solicitation, the agency laid out its requirements for 100 “Alpha” satellites that will be part of a mesh network known as Transport Layer Tranche 2. The Transport Layer Tranche 2 also includes 72 “Beta” satellites for which SDA already has requested bids. The procurement of 100 Alpha satellites will be split between two vendors. Each Alpha satellite will have three optical communications terminals, Ka-band and Link 16 payloads . These satellites will be part of a “communications network that will provide resilient, low-latency, high throughput data transfer to and from any location on the globe,” said SDA. SDA, an organization under the U.S. Space Force, is building a layered network of military satellites. The Transport Layer will serve as a tactical network to move data to users around the world, communicating classified data such as early warnings of missile launches. The constellation, which SDA calls the proliferated warfighter space architecture, includes a Transport Layer of interconnected communications satellites and a Tracking Layer of missile-detection and warning sensor satellites.

SDA is planning a new procurement for the Transport Layer Tranche 2, a mesh network of small satellites in low Earth orbit

 

Transport Layer Tranche 2 to launch in 2026

The agency already has acquired satellites for Tranche 0 and Tranche 1 of the Transport Layer and the Tracking Layer. The first launch of Tranche 0 satellites took place in April. Tranche 1 is projected to launch in 2024 and Tranche 2 in 2026.

The proliferated constellation is made up of small satellites supplied by multiple vendors, all interconnected via optical laser links.

The Transport Layer Tranche 2 will be SDA’s largest procurement to date.

SDA said Tranche 2, when deployed, will add enough nodes to the network to provide global coverage for U.S. military users.