Satellite launches from jets could soon become more common, as well as less expensive, with the development of new technology by the Defense Advanced Research Projects Agency (DARPA).
The Airborne Launch Assist Space Access (ALASA) program is designed to develop new technologies to bring small payloads to space at a far lower cost than using current systems.
"We've made good progress so far toward ALASA's ambitious goal of propelling 100-pound satellites into low Earth orbit (LEO) within 24 hours of call-up, all for less than $1 million per launch," Bradford Tousley, director of DARPA's Tactical Technology Office, said.
Defense Department satellites currently wait for years before launch, due to the scarcity of launch sites and liftoff opportunities. Currently, multiple satellites often launch together aboard single rockets.
"We envision an alternative to ride-sharing for satellites that enables satellite owners to launch payloads from any location into orbits of their choosing, on schedules of their choosing, on a launch vehicle designed specifically for small payloads," Mitchell Burnside Clapp, DARPA program manager for ALASA, said.
The new launch system under development would utilize a jet aircraft, cruising at great altitudes, as a first stage. A launch vehicle attached to the craft would be released, and fire engines, propelling the desired payload to orbit.
SpaceX currently provides some of the least expensive deliveries into space, with launch costs around $55 million.
Phase one of development selected three possible designs to place small satellites into space at a cost of one million dollars or less. Boeing was awarded the contract to complete development of the second phase of the project, including advanced composite structures and avionics.
A monopropellant, combining fuel and oxidizer into a single liquid, is being tested for use aboard the launch vehicle. If these tests are successful, this development could bring about simpler, less expensive launch systems, reducing launch delays and costs.
Infrastructure costs for satellite launches could also be reduced through the use of runways, as opposed to vertical launch sites. As the launch vehicle lifts a satellite to orbit, the craft will be tracked using existing satellites in space, rather than ground-based observatories. Further cost reductions could also be achieved through the use of automated flight-termination systems to constantly monitor conditions during the flight, and terminate the mission when necessary.
"We're moving ahead with rigorous testing of new technologies that we hope one day could enable revolutionary satellite launch systems that provide more affordable, routine and reliable access to space," Tousley stated in a DARPA press release.
Assuming monopropellant tests are successful, the first flight demonstration is planned for late 2015, with the first orbital insertion scheduled for the first half of 2016. A total of 12 test flights are currently being planned.
