WASHINGTON — The Space Development Agency on Oct. 8 issued a draft request for bids for 18 satellites that will carry experimental payloads. These 18 spacecraft will be integrated with SDA’s planned mesh network of 126 optically interconnected data transport satellites. 

SDA is already reviewing bids for the 126 satellites that will make up the Transport Layer Tranche 1, projected to launch in 2024. The additional 18 satellite are for the Tranche 1 Demonstration and Experimentation System, or T1DES.

According to the draft request for proposals, “T1DES will augment the Tranche 1 Transport Layer constellation with demonstration and experimental capability.”

The plan is to deploy the 18 satellites in a single plane about 600 miles above Earth, a mix of 12 satellites carrying industry-developed payloads and six with government-furnished payloads. The initial draft RFP said up to three vendors would be selected to produce the satellites and secure launch services by 2025. The request was updated Oct. 12 saying that SDA will only make one award.

SDA will not publicly discuss what types of payloads it is seeking. The portion of the RFP that specifies the desired payloads is only being released to approved vendors or those with secret security clearances. 

The agency said the Transport Layer will support multiple Defense Department customers and branches of the military. Government-development experimental payloads are likely to come from the Defense Advanced Research Projects Agency and the Air Force Research Laboratory. For the industry-developed payloads, SDA would be interested in sensors and other technologies that support DoD’s strategy to use satellites in space to track targets on the ground, at sea and in the air and share that intelligence across military platforms deployed around the world. 

T1DES satellites must use Ka-band frequencies and require two optical terminals for inter-satellite communications. The contractors have to provide complete integrated satellites and contract for launch services under agreements known as “delivery in orbit.”

Sandra Erwin writes about military space programs, policy, technology and the industry that supports this sector. She has covered the military, the Pentagon, Congress and the defense industry for nearly two decades as editor of NDIA’s National Defense...