The U.S. Space Force Space Development Agency (SDA) is planning a simultaneous, inaugural launch of Tranche 2 Transport Layer (T2TL) Beta and Alpha satellites by Sept. 1, 2026, SDA said in a draft T2TL Alpha solicitation last week.

“T2TL establishes initial launch capability (ILC) in September 2026 with the co-manifested launch of a highly inclined plane of four T2TL-Alpha and 12 T2TL-Beta SVs [space vehicles] and continues with an approximately year-long, monthly launch campaign involving the multiple T2TL variants,” SDA said. “As these SVs are placed into their insertion orbits, SDA will undergo a continuous checkout and commissioning process to prepare Tranche 2 for acceptance into operations conducted out of the Operations Centers (OCs) at Grand Forks, AFB (OC-N) and Redstone Arsenal, AL (OC-S).”

A month after the initial Tranche 2 Alpha/Beta Transport Layer launch, SDA plans to launch the first Alpha satellites in low inclination orbit.

SDA said that it intends to establish a government Test and Checkout Center (TCC) to speed the fielding of Tranche 2 at the operations centers in Grand Forks and Redstone Arsenal (Defense Daily, May 1). The Transport Layer, which is to field numerous low Earth orbit satellites about 600 miles above Earth, is a key part of the future Proliferated Warfighter Space Architecture (PWSA), which is to accelerate the provision of relevant, tactical information to combat forces.

The Grand Forks and Redstone Arsenal sites “will be operational in time to support Tranche 1 – the PWSA’s initial warfighting capability for BLOS [beyond line of sight] targeting and data transport and advanced missile detection and tracking,” SDA said last week. “Tranche 1 establishes ILC in September 2024 and will begin transitioning SVs to operations in 2025. As such, the Tranche 1 system will be conducting mission operations in the OCs at the time that Tranche 2 achieves ILC.”

Last month, SDA released the solicitation for the envisioned 72-satellite Beta constellation, which is to provide UHF and S-band tactical satellite communications using current radios. Beta is also to provide a mesh network with laser communication, laser communication to the ground, and Ka-band communication to the ground.

The final solicitation for 100 Link 16-enabled T2TL Alpha satellites, is to be released this summer. SDA plans call for the fielding of low-inclination and high-inclination Alpha satellites. Low-inclination satellites orbit near the Equator, while high inclination satellites orbit near the North Pole. SDA is to pick two winners of the T2TL Alpha competition, and each will build 38 low-inclination and 12 high-inclination satllites.

SDA plans to issue a final T2TL Gamma solicitation early in 2024. Those satellites are to include UHF and S-band and enhanced, anti-jam waveforms.

In February last year, SDA announced nearly $1.8 billion in awards to Lockheed Martin [LMT], Northrop Grumman [NOC], and York Space Systems for 126 prototype satellites for the Tranche 1 Transport Layer–the SDA’s first stab at fielding operational satellites to provide resilient, high volume, minimal lag time communications for military missions (Defense Daily, Feb. 28, 2022). Each contractor is to build 42 satellites to be ready for launch by September next year. Lockheed Martin won $700 million, Northrop Grumman $692 million, and York Space Systems won $382 million.

In addition, SDA said last October that York received a $200 million contract through 2031 for 12 Tranche 1 Demonstration and Experimentation System (T1DES) satellites to demonstrate tactical satellite communications and Integrated Broadcast Service from LEO.

Making the Tranche 1 ground segment “multilingual” to make sense of the data from various contractors’ satellites in the Tranche 1 Transport Layer, Tracking Layer, and T1DES is a significant technical challenge, an SDA official said in May last year upon SDA’s $324.5 million award to a General Dynamics [GD] and Iridium Communications Inc. [IRDM] team for the Tranche 1 ground operations and integration (O&I) segment (Defense Daily, May 27, 2022).

The General Dynamics/Iridium team is to provide the necessary network operations and command and control for SDA satellite operations centers at Grand Forks AFB, N.D., and Redstone Arsenal, Ala., to tie together the Tranche 1 satellite constellations.

SDA plans to make two awards for the Alpha Transport Layer satellites and is encouraging non-traditional bidders.

To qualify for an award, “at least one of the following conditions must be met,” SDA said. “There is at least one nontraditional defense contractor or nonprofit research institution participating to a significant extent in the prototype project; [or] all significant participants in the transaction other than the federal government are small businesses…or nontraditional defense contractors; [or] at least one third of the total cost of the prototype project is to be paid out of funds provided by sources other than the federal government.”