Lockheed Martin delivers 21 satellites for next launch of U.S. military ‘Transport Layer’

NATIONAL HARBOR, Md. — The Space Development Agency (SDA) is gearing up for its second launch of satellites for the Transport Layer Tranche 1 program. SDA is building out a low Earth orbit (LEO) mesh network for global military communications and missile defense.

Gurpartap “GP” Sandhoo, acting director of SDA, confirmed Sept. 22 that 21 satellites built by Lockheed Martin are on track to launch in October from Vandenberg Space Force Base, California. 

The upcoming mission follows the successful Sept. 10 deployment of 21 York Space Systems satellites — the first “plane” in the six-plane Transport Layer Tranche 1 constellation. Speaking at the Air Space & Cyber conference, Sandhoo said it will take several months for York to complete the testing of the satellites and raise them to the right orbit. 

SDA, an agency under the U.S. Space Force, is building the Proliferated Warfighter Space Architecture (PWSA), a multi-layered satellite network that includes both data transport and missile-tracking satellites.

The Transport Layer satellites are designed to provide beyond line-of-sight connectivity for the U.S. military’s Link 16 tactical data network. Link 16 is the primary digital communications backbone for U.S. and allied forces with a range limited to a few hundred miles. With satellite relay, those secure, jam-resistant messages could travel anywhere on Earth, creating a persistent battlefield data link. Tranche 1 satellites also carry optical communications terminals to pass data from satellite to satellite. 

Tranche 1 is structured as six orbital “planes.” Lockheed Martin, York Space Systems and Northrop Grumman are each responsible for two planes. 

Lockheed Martin said Sept. 22 that it has completed delivery of the 21 spacecraft for this mission. The company is building 42 satellites under a $700 million SDA contract awarded in February 2022. Each spacecraft is based on a bus supplied by Terran Orbital, a Lockheed subsidiary.

To handle the surge in SDA-related work, Lockheed opened a new Small Satellite Processing & Delivery Center in Littleton, Colorado.

“The low bay clean room is dedicated to the rapid development of small satellites,” said Joe Rickers, Lockheed Martin’s vice president for protected communications. “Clearly, we’ve had to set up the infrastructure to be able to really support the volume of satellites that SDA will be putting through.”

The company’s SDA pipeline doesn’t stop with Tranche 1. Lockheed is building 36 satellites for Transport Layer Tranche 2 and another 18 for Tracking Layer Tranche 2, which will serve as a missile-warning constellation.

With Tranche 1 planes launching in quick succession, SDA is pushing to demonstrate the resilience of proliferated LEO architectures that use hundreds of small, less-expensive satellites to make them more resistant to disruption or defeat compared to fewer, larger and more expensive satellites. Sandhoo said the per-unit average cost of Transport Layer satellites is about $14 million.