The U.S. Space Force’s Space Development Agency (SDA) has issued a solicitation for Tranche 2 (T2) of the SDA Tracking Layer for first launch by April 30, 2027.
“The T2 Tracking scope includes the procurement and deployment of 54 – and potentially more – space vehicles (SVs) with infrared (IR) sensors in six orbital planes,” SDA said in a business notice. “The fully deployed Tracking Layer is estimated to include more than 100 SVs in low Earth orbit (LEO) across multiple planes.”
In January, SDA renamed its planned proliferated LEO constellation as the Proliferated Warfighter Space Architecture (PWSA).
“SDA has determined that the proliferation of various mission functions across the PWSA using commodity SVs is the most efficient and cost-effective means of evolving the architecture,” SDA said in the Tranche 2 Tracking Layer solicitation. “The objective is to establish and demonstrate the ability to rapidly evolve development processes and field capability on a significantly faster timeline than historical space systems acquisition. In pursuit of this objective, SDA requires each PWSA performer’s SVs and communications systems to be interoperable with the SVs and systems developed by all other PWSA performers as well as those to be deployed in Tranche 1. Additionally, all SVs must operate in an integrated fashion through a common ground system.”
SDA said that it plans to award more than one company contracts under the Tranche 2 Tracking Layer. The agency established several conditions to qualify for an award, including having “one nontraditional defense contractor or nonprofit research institution” on a contractor team or having “at least one-third of the total cost of the prototype project paid out of funds provided by sources other than the federal government.”
SDA plans to begin fielding the Tranche 1 satellites–the first for military operations–late next year. Tranche 1 is to include about 150 Transport Layer and Tracking Layer satellites.
The SDA Transport Layer satellites are to provide rapid sensor to shooter data, while the Tracking Layer satellites are to provide a significant leap in the detection and tracking of hypersonic and ballistic missiles.
SpaceX and L3Harris [LHX] are the contractors for the Tranche 0 Tracking Layer, while L3Harris and Northrop Grumman [NOC] are building 28 satellites for the Tranche 1 Tracking Layer (Defense Daily, July 20).
“Each SV is equipped with an IR mission payload, Optical Communications Terminals (OCTs), and Ka-band and S-band communications payloads,” SDA said in the Tranche 2 Tracking Layer solicitation. “Select SVs will be equipped with a directed energy sensor.”
The latter is to provide satellite defense against directed energy attacks. The solicitation said that bidders “shall implement some additional methods for enhancing resiliency of selected mission payloads against threats such as directed energy effects.”
“The government is interested in mature elements or components that enhance Tracking constellation resiliency, particularly the IR payload sensor,” per the solicitation. “The offeror shall provide a directed energy resiliency system that at minimum includes a directed energy threat warning sensor. The offeror shall provide a feasible SV CONOPs that could be implemented to enhance survivability, thus providing the capability to continue IR mission operations during directed energy illumination.”
Tucson-based LightRidge Solutions‘ GEOST operating unit said this week that Northrop Grumman has chosen GEOST to provide its “Starlite resiliency payload for Tracking Layer Tranche 1 satellites.” GEOST said that it will provide eight Starlites, each about “the size of a can of soda,” and a ground system for the Tranche 1 Tracking Layer.
For the six orbital planes of the Tranche 2 Tracking Layer, “each plane of nine SVs will include eight SVs equipped with MW/MT [Missile Warning/Missile Tracking] infrared (IR) mission payloads to achieve near-continuous global stereoscopic coverage for Missile Warning and Missile Tracking,” according to the solicitation. “The ninth SV in each plane will be equipped with an IR mission payload capable of generating fire control quality tracks for missile defense. This system includes on-orbit calibration capability, on-board processing of tracking data, and minimization of solar outages. Each SV will have multiple pointing modes to include Nadir- and Ram-Fixed, Off-Earth Inertial Point/Track, Sun Pointing, Solar Avoidance Pointing, and Safe. The SVs must be able to conduct continuous operations without power or thermal constraints.”
This month, a SpaceX Falcon 9 rocket launched 13 satellites from Vandenberg Space Force Base, Calif., for the SDA’s Tranche 0 effort (Defense Daily, Sept. 5).
The second Tranche 0 launch included 10 Lockheed Martin [LMT] Transport Layer satellites, one York Space Systems’ Transport Layer satellite, and two SpaceX Tracking Layer satellites.
The 10 Lockheed Martin Tranche 0 Transport Layer satellites have the company’s SmartSat modular software; a Terran Orbital [LLAP] bus/processors; and Link 16 radios to link fighter aircraft and integrated air and missile defense networks through space, Lockheed Martin said.
In addition to the 10 Tranche 0 Transport Layer satellites, Lockheed Martin is on contract to build 42 Tranche 1 Transport Layer satellites and 36 Beta variant satellites for the Tranche 2 Transport Layer at Lockheed Martin’s newly opened small satellite plant in Littleton, Colo.
On Apr. 2, SDA conducted the first Tranche 0 launch–of eight York Space Systems Transport Layer satellites and two Space X Tracking Layer satellites.
Last month, SDA said that it plans to launch the remaining four Tranche 0 Tracking Layer satellites by L3Harris later this year in a collaborative launch with the Missile Defense Agency (Defense Daily, Aug. 30).
SDA has said that tardy deliveries of microelectronics and space system components for Moog, Inc. [MOG-A]-built satellite buses for the four L3Harris Tranche 0 Tracking Layer satellites have delayed launches.