WASHINGTON — A SpaceX Falcon 9 rocket on Oct. 15 launched 21 satellites to low Earth orbit for the U.S. Space Force’s Space Development Agency. This was the second deployment of satellites for SDA’s mesh network known as the Transport Layer.
The mission lifted off at 7:06 p.m. Eastern from Vandenberg Space Force Base, California.
This was the second plane of satellites for Tranche 1 of the Transport Layer, part of a planned global network of data transport and sensor satellites known as the Proliferated Warfighter Space Architecture (PWSA).
The Space Development Agency was established in 2019 to break the Pentagon’s reliance on large geostationary satellites by instead deploying networks of smaller spacecraft in low Earth orbit built using commercial components and rapid acquisition methods.
The 21 satellites launched on Wednesday were built by Lockheed Martin. The company in 2022 won a $700 million contract to produce 42 satellites for the Tranche 1 constellation. The spacecraft buses were supplied by Terran Orbital, a Lockheed Martin subsidiary.
“These data transport satellites will provide unprecedented levels of space-based connectivity for national security situational awareness, enabling our forces to respond faster to emerging threats,” said Joe Rickers, vice president of Transport, Tracking & Warning programs at Lockheed Martin.
York Space and Northrop Grumman also are supplying Tranche 1 Transport Layer satellites. The first plane of Transport Layer satellites launched Sept. 10.
The Transport Layer is designed to provide beyond line-of-sight connectivity to military forces worldwide. A key goal is to enable users operating on the Link 16 tactical data network — the U.S. military’s primary battlefield communication system — to relay secure, real-time messages around the globe through satellite relays. This capability expands the range of Link 16 radios from a few hundred miles to virtually any location on Earth.
The first customers for SDA’s mesh network will be U.S. Indo-Pacific Command forces that are seeking improved data connectivity and persistent coverage vital to operations in the vast Pacific theater.
The Transport Layer satellites are equipped with optical inter-satellite communication terminals.
The Space Development Agency plans to launch 10 “planes” of Tranche 1 satellites — a plane being a set of satellites arranged in the same orbital path to provide continuous regional coverage. Tranche 1 will include six Transport Layer launches and four Tracking Layer launches. The Tranche 1 constellation consists of 126 Transport Layer data relay satellites and 28 missile warning and tracking satellites scheduled to launch over the coming year.
Lockheed Martin, York Space Systems and Northrop Grumman are each responsible for two Transport Layer planes.