SpaceX launches the second batch of the SDA’s Tranche 0 satellites on Sept. 2. Photo: SpaceX

A SpaceX Falcon 9 rocket lofted 13 satellites for the U.S. Space Force’s Space Development Agency (SDA) Tranche 0 effort into orbit on Sept. 2 from Vandenberg Space Force Base, California.

The second Tranche 0 launch included 10 Lockheed Martin Transport Layer satellites, one York Space Systems’ Transport Layer satellite, and two SpaceX Tracking Layer satellites. The SDA Low-Earth Orbit (LEO) Transport Layer satellites are to provide rapid beyond line-of-sight targeting data and sensor fusion, while the LEO Tracking Layer satellites are to provide a significant leap in the detection and tracking of hypersonic and ballistic missiles.

The Falcon 9 “deployed the satellites into an insertion orbit where SDA will begin test and checkout procedures, which will eventually include orbit raising to reach the intended orbit at approximately 1,000 km.,” the SDA said on Sept. 2. “Tranche 0 ground support is provided by the U.S. Naval Research Laboratory.”

The 10 Lockheed Martin Tranche 0 Transport Layer satellites have the company’s SmartSat modular software; a Terran Orbital 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 week, 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.

Mike Eppolito, SDA’s Tranche 0 program director, said that the planned, third Tranche 0 launch this year was the result of delays in satellite delivery and a “leadership decision” to demonstrate MDA and SDA Tracking Layer satellites by L3Harris “in the same plane to see the same targets demonstrating both medium field of view and wide field of view tracking payloads.”

SDA has said that delayed deliveries of microelectronics and space system components for Moog, Inc.-built satellite buses for the four L3Harris Tranche 0 Tracking Layer satellites have affected launch timelines.

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.

This article was first published by Defense Daily