Space

SDA taps York for 62 Tranche 2 Transport Layer data relay sats to provide ‘global’ coverage

"Here's the beauty of the spiral development program. I don't know what Tranche 3 looks like. All I know is it's more of what was on Tranche 2, and it is most likely going to be new capabilities," SDA Director Derek Tournear said Thursday. "I don't want to define what those capabilities are now."

Space Development Agency Director Takes Part in Defense One Event
Space Development Agency Director Dr. Derek Tournear. (DoD photo by Lisa Ferdinando)

Milsat Symposium 2023 — The Space Force’s Space Development Agency (SDA) this week awarded a contract for 62 data relay satellites in its planned Transport Layer mesh network in low Earth orbit to provide military users high-speed, high-volume data communications world-wide, SDA Derek Tournear said Thursday.

The satellites will be part of the agency’s Tranche 2 Transport Layer configuration that will provide “global access” to the Transport Layer for warfighters on the ground, he told the Milsat Symposium in Mountain View, Calif.

Tournear told Breaking Defense after his presentation that though it hasn’t been officially announced yet, the contract was finalized on Tuesday — and an SDA spokesperson today said that it is valued at “over $615 million,” including “an incentive payment for on-time delivery.”

The Tranche 2 Transport Layer will comprise 216 satellites total, made up of three satellite variants called Alpha, Beta and Gamma — and the York contract is for the Alpha variants, he told the Milsat audience.

SDA now is in negotiation with a a second vendor for the other 38 Alpha satellites being planned, and hopes to “close on” that contract “early next week.”

The Alpha variants will carry optical inter-satellite crosslinks (i.e. laser cross-links), a Ka-band communications downlink, on-board battle management processing and a Link 16 data link for machine-to-machine connection with current platforms such as aircraft and ships.

SDA in August awarded Northrop Grumman and Lockheed Martin a total of $1.5 billion to build and operate 72 Beta Tranche 2 Transport Layer birds. The Beta satellites will carry laser cross-links and a UHF Tactical Satellite Communications (TacSATCOM) downlink for tactical users.

Tournear said that SDA originally planned to orbit 44 of the Gamma satellites, which will carry an “advanced tactical data link,” but is now revamping its approach and is likely to shift 24 of those to the Beta configuration.

“At least we’re in negotiations with a third Beta vendor right now to do that,” he said.

Transport-Layer_mesh-network_square_final584
SDA’s Transport Layer of data relay satellites will be linked together in a mesh network stationed in low Earth orbit. (Graphic: Space Development Agency)

Somewhat confusingly, Tranche 2 is actually the third planned spiral development iteration of the Transport Layer that Tournear said will eventually include some 400 satellites.

The agency already has launched 19 Tranche 0 Transport Layer test satellites built by York and Lockheed Martin.

It intends to launch the first of its Tranche 1 Transport Layer birds, designed to provide regional coverage, in September of 2024. SDA in February 2022 awarded $1.8 billion in contracts to York Space Systems, Northrop Grumman and Lockheed Martin for development of the 128 Tranche 1 Transport Layer satellites.

The Transport Layer, in turn, is part of the agency’s planned Proliferated Warfighter Space Architecture, designed to flummox enemy attacks by making targeting much more difficult through the tyranny of numbers. SDA is also planning to acquire about 100 missile warning/tracking satellites for its Tracking Layer optimized to keep tabs on not just ballistic but also hypersonic missiles, and is pursuing those satellites in tandem with the Transport Layer birds in each of the Tranche 0, Tranche 1 and Tranche 2 spirals.

Tournear said that following the Tranche 2 Transport and Tracking Layers, there will be a Tranche 3, but what capabilities those will include remains unclear as of now.

“Here’s the beauty of the spiral development program. I don’t know what Tranche 3 looks like. All I know is it’s more of what was on Tranche 2, and it is most likely going to be new capabilities,” he said. “I don’t want to define what those capabilities are now.”

But what is for sure, he added, is that Tranche 3 will begin launch in September 2028.

PHOTOS: AFA 2025

PHOTOS: AFA 2025

Space Force Chief of Space Operations Gen. B. Chance Saltzman delivers his keynote address, Sept. 23, 2025. (Jud McCrehin/Air & Space Forces Association)
Jay Raymond (left), former Space Force chief of space operations, and David Thompson, former vice chief of space operations, speak on a panel moderated by Nina Armagno, former Space Force staff director, Sept. 23, 2025. (Jud McCrehin/Air & Space Forces Association)
Griffon Aerospace displays its Valiant vertical takeoff-and-landing drone, designed for field reconnaissance on the go, Sept. 23, 2025. (Aaron Mehta/Breaking Defense)
Trac9 shows its Advanced Deployable Aircraft Mobile System, a portable hangar, Sept. 23, 2025. (Aaron Mehta/Breaking Defense)
A model of Saab-Boeing's T-7 Red Hawk jet trainer, Sept. 23, 2025. (Daniel Woolfolk/Breaking Defense)
A 1/6th-size model of the Hermeus supersonic jet sits below a live feed of the company's production line in Atlanta, Ga., Sept. 23, 2025. (Aaron Mehta/Breaking Defense)
Shield AI's V-BAT vertical takeoff-and-landing drone, sits on display, Sept. 23, 2025. (Daniel Woolfolk/Breaking Defense)
The Air Force Research Laboratory displays a missile designed under its "Angry Tortoise" program, a partnership with Ursa Major, that looks to develop hypersonic missiles that can be deployed en masse for millions of dollars less than more traditional munitions, Sept. 22, 2025. (Rachel Cohen/Breaking Defense)
Anduril’s YFQ-44A Fury drone, an entrant in the Collaborative Combat Aircraft drone wingman program, sits on display, Sept. 22, 2025. (Daniel Woolfolk/Breaking Defense)
General Atomics’ YFQ-42A, another CCA entrant, sits on display, Sept. 22, 2025. (Rachel Cohen/Breaking Defense)
JetCat shows several small jet engines designed to power munitions or kamikaze drones at a fraction of the cost of larger engines, Sept. 22, 2025. (Rachel Cohen/Breaking Defense)
Sierra Nevada Corp.’s Battery Revolving Adaptive Weapons Launcher (BRAWLR), a reconfigurable counter-drone system in use by at least one classified foreign customer, makes its defense trade show debut, Sept. 22, 2025. (Rachel Cohen/Breaking Defense)
Air Force Undersecretary Matt Lohmeier visits the Northrop Grumman booth, where the Stand-In Attack Weapon and Hypersonic Cruise Missile are on display, Sept. 22, 2025. (Rachel Cohen/Breaking Defense)
The Tactical Combat Training System Increment II connects live aircraft to a simulator in training, allowing remote troops to practice in real-world conditions. (Rachel Cohen/Breaking Defense)

Could you fly Embraer’s C-390? (Daniel Woolfolk/Breaking Defense)

Embraer aims to convince the Air Force that its C-390, shown in miniature on Sept. 24, 2025, could be a boon to the service’s airlift fleet. (Daniel Woolfolk/Breaking Defense)
J.P. Nauseef, president and chief executive officer of JobsOhio speaks during ASC, Sept. 24, 2025. (Jud McCrehin/Air & Space Forces Association)
Attendees traverse the show floor on the final day of the conference, Sept. 24, 2025. (Daniel Woolfolk/Breaking Defense)
Attendees mill about near the main show floor doors at the Gaylord National Resort & Convention Center, Oxon Hill, Md., Sept. 24, 2025. (Daniel Woolfolk/Breaking Defense)
RTX shows off munitions at its booth on the show floor, Sept. 22, 2025. (Rachel Cohen/Breaking Defense)