Space Development Agency slows satellite launches to focus on on-orbit performance

WASHINGTON — The Space Development Agency is slowing the pace of launches for the Pentagon’s low Earth orbit satellite constellation, stepping back from an earlier plan for frequent deployments as it works through technical issues with spacecraft already in orbit.

Gurpartap “GP” Sandhoo, the agency’s acting director, said the next launch of the Proliferated Warfighter Space Architecture’s Tranche 1 satellites will not occur until at least May or June, marking a gap of roughly seven months since the last launch in mid-October. The pause is intentional, he said, as the program shifts from rapid deployment to validating performance on orbit.

“We plan to start launching again towards the May, June timeframe,” Sandhoo said March 23 at the Satellite 2026 conference.

So far, 42 of the 154 satellites planned for Tranche 1 have been launched. Those spacecraft — all part of the Transport Layer — include 21 satellites built by York Space Systems and 21 by Lockheed Martin.

The decision reflects a shift in what is driving the program. Rather than launch availability, Sandhoo said, the pacing factor is now the work required to bring satellites into operational use — raising them to final orbits, checking out systems and demonstrating early integration.

After initial testing, “we saw a handful of things, and we kind of stopped to make sure we fix those for the next set of launches,” he said.

Tranche 1 represents the first operational step in building a distributed missile warning and data network in low Earth orbit. It combines two elements: a Tracking Layer of infrared sensor satellites that detect and follow missile threats, and a larger Transport Layer that relays that data across space using optical intersatellite links and delivers it to ground systems and military users.

The architecture is designed to function as an integrated network, with tracking satellites generating missile track data and transport satellites moving that information in near real time.

Standing up that network is proving more complex than anticipated. The system depends on interoperability across multiple vendors, requiring coordination among satellites, communications links and ground systems. Establishing that connectivity, particularly a mesh network using laser communications, remains an unresolved step.

“We have not established the mesh network for Tranche 1 yet,” Sandhoo said.

All PWSA satellites are equipped with optical intersatellite terminals, supplied by companies including Mynaric, Tesat Spacecom, Skyloom and CACI. While those terminals have been tested on the ground, SDA still must demonstrate that they function as intended in orbit. The process is running behind schedule.

“We are going through orbit raising, and that’s where we are,” Sandhoo said. “We are about three months behind.”

Lockheed Martin is expected to begin orbit-raising maneuvers for its satellites this week, with optical link testing to follow.

Challenges of a large constellation

The delays highlight the challenges of deploying a large, networked constellation, a model the Pentagon has not previously attempted at this scale. While the Defense Department has operated satellite constellations before, it has not managed hundreds of interconnected spacecraft deployed in rapid succession across multiple contractors.

Tranche 1 alone is structured across 10 orbital planes and will ultimately include 126 Transport Layer satellites and 28 Tracking Layer satellites. Lockheed Martin, York Space Systems and Northrop Grumman are responsible for Transport Layer planes, while L3Harris Technologies and Northrop Grumman are supplying Tracking Layer satellites.

The program’s original concept called for a steady cadence of launches, potentially as often as monthly. ThatC approach has proven unrealistic in early phases as the agency works through the mechanics of turning launched satellites into a functioning network.

The post-launch testing process itself is split between contractors and the government. Manufacturers conduct initial spacecraft checkout from their own facilities, validating core functions such as power and propulsion. Once those steps are complete, payload testing shifts to classified ground stations operated by SDA in Huntsville, Alabama, and Grand Forks, North Dakota, where the satellites’ mission performance and integration with military systems are evaluated.

That handoff adds coordination complexity, particularly in a multi-vendor architecture where systems must operate together seamlessly.

The slowdown underscores a broader tension in the program between speed and performance. SDA was established to accelerate space acquisition by fielding capabilities quickly in incremental tranches. But as the first operational layer is deployed, the focus is shifting toward ensuring those systems work as intended before scaling further.