The Space Development Agency aims to field multiple interrelated satellite constellations that it calls layers. Credit: Space Development Agency graphic

The Space Development Agency had a rough start. Its first director quit just three months into the job and there has been mounting speculation about its future. Despite strong backing within the Pentagon, the SDA is still trying to win over skeptics on Capitol Hill and secure funding for the fiscal year that begins Oct. 1.

These early difficulties have not deterred the SDA’s skeleton crew of 27 civilian government workers and staff contractors led by acting director Derek Tournear. “We have strong support in the Department of Defense, and more people on Capitol Hill are now understanding our role,” Tournear tells SpaceNews in a recent interview.

Derek Tournear was named acting director of the Space Development Agency in June. Credit: DoD

SDA currently resides under the Office of the Undersecretary of Defense for Research and Engineering. The head of that office, former NASA Administrator Mike Griffin, was a forceful advocate for the creation of SDA, arguing that a separate agency is needed to help bring lower cost commercial space technology into military systems.

Tournear was named acting director June 24, five days after SDA’s hand-picked leader Fred Kennedy resigned upon learning that Griffin was looking to replace him. Tournear was serving as Griffin’s assistant director for space when he was tapped to fill Kennedy’s post.

While Kennedy is well known in government and industry circles, few people have heard of Tournear, a former Harris Corp. and ITT Exelis Geospatial Systems executive who also worked in the intelligence community and at the Defense Advanced Research Projects Agency after earning his doctorate in physics at Stanford University in 2003 and spending four years at Los Alamos National Laboratory. Amid the bad press SDA received following Kennedy’s departure, Griffin and Tournear made regular trips to Capitol Hill to answer questions from leery lawmakers.

Sources told SpaceNews last week that Griffin has selected Tournear to be the SDA’s permanent director and that his appointment will be announced in the coming days.

SDA received a welcome boost Sept. 12 when the Senate Appropriations Committee voted to approve the Pentagon’s 2020 budget request for the agency: $44.7 million for personnel, $20 million for space research and development, and $85 million for space technology prototyping. House appropriators, however, were less supportive and cut SDA’s funding request out of concern that it is duplicating existing Air Force programs. The House Appropriations Committee cut the personnel funding request to $26.8 million, and the prototyping technology request to $35 million although it fully funded the $20 million request for R&D. The final funding levels will be negotiated in a House-Senate appropriations conference.

Uncertainty and confusion about SDA are not going to disappear overnight but attitudes are changing, Tournear says. He is buoyed by the show of support by Defense Secretary Mark Esper and Deputy Defense Secretary David Norquist, both of whom told lawmakers in their confirmation hearings that SDA was a needed asset in the Defense Department. Tournear predicts that SDA will have about 100 engineers, scientists and support contractors on its payroll by this time next year. A permanent director will be named soon, he says.

If Congress enacts a U.S. Space Force as a separate branch of the military, the plan is to realign SDA under the new service so it can serve as its acquisition arm. Alabama and New Mexico lawmakers are lobbying DoD to move SDA to their states. Tournear says SDA for now will remain in the Pentagon.

With growing confidence that Congress will provide resources to move forward, SDA has started to solicit ideas from the private sector and is scoping out the market. A Request for Information released July 1 generated 150 responses, says Tournear. They ranged from broad architecture concepts to white papers focused on specific components. Before the end of 2019, he says, the agency will issue Broad Area Announcements (BAAs) asking contractors to bid for specific technology demonstrations.


The demonstrations are the first step toward the development of interrelated constellations of satellites that SDA calls layers. The immediate priority is the transport layer, a mesh network of satellites in LEO that will provide global communications. Next is the tracking layer, projected to be a large LEO constellation of surveillance satellites to identify the location of incoming missile threats.

Other layers will follow. A custody layer will monitor targets in the battlefield such as moving vehicles. A deterrence layer in much higher orbits will keep an eye on the cislunar space. A navigation layer will offer an alternative to GPS for positioning, navigation and timing. A battle management layer will use artificial intelligence to deliver targeting data to commanders on the ground.

The first BAA will ask for proposals to demonstrate the transport layer, which SDA considers foundational to all the other layers as they all require reliable 24/7 communications.

A demonstration might consist of as few as two satellites, Tournear says. The transport satellites will talk to each other via optical crosslinks and will have to communicate with aircraft and other weapon systems.

The second BAA will be for the tracking layer. SDA wants contractors to propose different phenomenologies to detect and track advanced weapons such as hypersonic missiles. Tournear says that will help SDA determine what frequencies should be used with different types of sensors. During a meeting with reporters Sept. 18 at the Air Force Association’s annual conference, Tournear said the tracking layer might be deployed at higher altitude orbits than previously planned — at 1,000 to 1,500 kilometers, instead of 400 to 500 kilometers — in order to provide global coverage with fewer satellites.

If all goes as planned, the transport and tracking layers will be tested over the next two years and enter production in 2022, with the goal to have an operational system by 2024. Tournear says the other layers will take longer. The deterrence layer will be a “limited capability” by 2026 or 2028. Conceivably, two satellites would be deployed in highly elliptical orbits to monitor cislunar space — the region between the Earth and the moon — for any nefarious activity. “We’ll be able to assign attribution and detection before an event,” he says. Another option being considered for the deterrence layer is an “advanced maneuvering vehicle” that would operate in the cislunar space to inspect something closer.

“In 2024, we will have regional persistent coverage for our advanced missile tracking layer,” he says. “And we’ll have a mesh network to allow sensors to plug into that. And we’ll have regional persistent coverage for our custody layer.” Tournear points out that SDA will be responsible to field the transport layer but the tracking layer is a joint effort with the Missile Defense Agency.

Tournear pushes back on the suggestion that SDA is in competition with the Missile Defense Agency, the 17-year-old acquisition and R&D agency that also resides under Griffin’s office. “We are working with MDA and others to ensure that what they build fits into the architecture. With MDA, we’ve been working extremely closely,” he says. “Our vision is that MDA will build out the tracking layer in coordination with SDA to make sure it plugs into the overall architecture.”

The Pentagon’s 2020 budget request includes nearly $150 million to grow the Space Development Agency to approximately 100 engineers, scientists and support contractors by this time next year. Senate appropriators in September approved $149.7 million for SDA while House appropriators approved just $81.8 million. Credit: Space Development Agency chart


At SDA’s first Industry Day, held in late July in Chantilly, Virginia, more than 300 executives from commercial space and traditional defense companies showed up. According to SDA officials, dozens were turned away as the agency had not planned for such a large turnout.

Tournear says there is growing enthusiasm in the business community about SDA. He meets regularly with defense and space companies, including those that are now building large broadband constellations comparable to the transport layer that SDA envisions. He often must explain to audiences that the SDA transport layer will not be like a commercial system. It will use commercial buses and other components available in the open market, but it will be owned by the government and will not be made by a single contractor. “We’re going to leverage commercial technology,” he says. “But we are not going to rely on commercial constellations or commercial industry to be our backbone. Our mission is not going to be dependent on the success of a commercial company.”

To build the transport and tracking layers, SDA plans to procure hundreds of satellites. “We’re talking about going into production building one satellite a week for many years into the future,” says Tournear. The buses will be bought directly from commercial vendors or SDA might use some of the same buses that the Defense Advanced Research Projects Agency is acquiring for Blackjack, a program that seeks to develop a LEO constellation prototype. Most payloads are specific to DoD and likely will have to be developed, he says. “The sensing payloads are not commercially available; there is no commercial need for advanced missile tracking.” Some payloads like optical crosslinks already have been funded by DARPA or are sold by commercial vendors.

SDA plans to work with multiple contractors and resists the idea of consolidating the work under one company. “We are not going to rely on a single vendor to build out a single layer,” says Tournear. “That will ensure we have resilience and that we force an open architecture” so all satellites talk to each other regardless of who made them.

Ground systems also will be purchased from commercial providers. For the demonstrations, SDA will probably lease time on commercial ground stations, says Tournear. For the operational systems down the line, the plan is to integrate the SDA layers into the ground enterprise that the Air Force’s Los Angeles-based Space and Missile Systems Center is developing to command and control all military satellites.

SDA does not intend to develop user terminals and will make sure the satellites it deploys can communicate with existing user equipment. This is a critical issue for DoD because it has tens of thousands of terminals deployed around the world with ground forces and aboard aircraft and ships. “Our transport layer will communicate targeting solutions to 90% of currently fielded weapon systems,” says Tournear. “We’re going to talk directly to weapon systems,” he adds. “That is one of the areas we feel most confident in. When we talk to an aircraft, it’s going to be over an existing waveform. Whatever capabilities we provide, we want to make sure we get to the shooter. That is the end goal.”

One of the catchphrases of SDA is that it is a “threat-driven” agency. While all weapons acquisitions are in some way driven by a national security imperative, SDA will move faster than traditional procurements, Tournear says. SDA will focus on delivering equipment in one- or two-year cycles and continuing to improve it as new technology becomes available, in a similar fashion as the software industry develops products. “We don’t want the perfect to be the enemy of the good enough.”

This article originally appeared in the Sept. 23, 2019 issue of SpaceNews magazine.

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...