SAN FRANCISCO — The U.S. Defense Advanced Research Projects Agency (DARPA) is seeking proposals for innovative ways to dramatically lower the cost of sending satellites into orbit by launching them from aircraft.

The Airborne Launch Assist Space Access (ALASA) program, announced Nov. 3 in a posting on the Federal Business Opportunities website, is designed to reduce by two-thirds the cost of sending a 45-kilogram satellite into low Earth orbit and to offer a quick-response option for government agencies seeking to deploy new capabilities or reconstruct existing constellations.

Through ALASA, DARPA is seeking to develop a new rocket that would require no “specific integration to prepare for launch” and would cut the cost of sending small satellites into orbit from a current level of more than $66,000 per kilogram to $22,000 per kilogram. The idea is to draw on a variety of emerging technologies, including powerful propellants, motor case materials, flight controls and nozzle designs, according to the DARPA announcement.

ALASA is the latest in a series of DARPA initiatives stretching back more than two decades to spur development of air-launched rockets designed to free satellite program managers from the expense, geographic limitations and schedule rigidity of standard launch ranges. In 1988, DARPA began development of the Pegasus air-launched rocket to offer an inexpensive, responsive small-satellite launch capability. While that program led to a system that is in operation today, more recent DARPA air-launch efforts have been halted.

In 2003, DARPA unveiled a five-year plan to develop a system featuring an aircraft that would carry an expendable rocket to a high altitude and then release it to loft a 50- to 150-kilogram payload into orbit. That effort, known as Responsive Access Small Cargo Affordable Launch, was canceled two years later due to high costs. In 2008, DARPA and the Air Force also halted testing of the QuickReach booster, a rocket designed by AirLaunch LLC of Kirkland, Wash., to send small satellites into orbit on a rocket that dropped from the cargo bay of a U.S. Air Force C-17 cargo jet.

Gary C. Hudson, former AirLaunch founder and chairman, said DARPA is nonetheless wise to continue exploring the idea of air-launched rockets. “Any air-launch program is a smart approach in my view,” Hudson said in a Nov. 8 email. “Air launch offers powerful advantages such as first-orbit rendezvous, reduced range safety costs and launch azimuth flexibility, not to mention eliminating heavy infrastructure cost at the launch site.”

During a Nov. 4 industry briefing in Arlington, Va., DARPA’s ALASA program manager, Mitchell Burnside Clapp, invited industry teams to submit proposals by Dec. 20 for a one-year technology and systems design phase that is expected to include five or more participants. The next phase, focused on technology maturation and systems demonstration, would culminate in flight tests in late 2014 and rocket launches in 2015, according to a PowerPoint presentation shown at the briefing.

Specifically, DARPA is seeking a new rocket that can be prepared for launch within a single day, send satellites into a variety of specific orbital locations and demonstrate that even if the intended airfield is under attack, the plane can take off and execute the mission from another location, according to the briefing charts.

Some industry observers questioned the rationale for ALASA’s proposed payload-lifting capacity. In June, DARPA and NASA issued an interim report on a study of horizontal launch systems designed to carry 6,800 kilograms into low Earth orbit. “It’s a shame that path can’t be followed, since the level of effort it takes to develop a [45-kilogram] payload launcher is about the same as the level it takes to develop a larger launcher,” one industry official said. “This has been demonstrated by [Space Exploration Technology Corp.’s] Falcon 1 and Falcon 9. They use essentially the same engines, avionics and launch procedures with the principal difference being the airframes.”

Debra Facktor Lepore, industry professor at Stevens Institute of Technology in Hoboken, N.J., and former AirLaunch president, said she would have expected DARPA to pursuer a bigger vehicle. “$1 million per flight is this magic number that everyone has tried to achieve and no one has succeeded. Perhaps a solution would be to increase the size of the payload and the cost per flight” while keeping that cost under $22,000 per kilogram, she said.

A.C. Charania, chief executive of Generation Orbit Launch Services, said the focus on small payloads makes sense in the context of DARPA’s investments in developing nanosatellites. Examples include the System F6 program, which seeks to replace large, stand-alone satellites with clusters of small, networked spacecraft, and the Phoenix program, which would employ small satellites to harvest and reuse antennas or space apertures on orbiting spacecraft that are no longer operating.

“The ALASA program is a needed attempt at DARPA to develop a robust and useful service for a new generation of military customers,” Charania said in a Nov. 10 email. “The investments DARPA has and is making in nanosatellites can be coupled with this investment in ALASA to achieve a programmatic force multiplier effect.”

Generation Orbit, a new company based in Atlanta, hopes to establish a launch service that uses existing or modified rockets that would deploy from jet aircraft to send satellites weighing 30 kilograms or less into low Earth orbit.


Debra Werner is a correspondent for SpaceNews based in San Francisco. Debra earned a bachelor’s degree in communications from the University of California, Berkeley, and a master’s degree in Journalism from Northwestern University. She...