The United States military has abandoned its plans to launch satellites using F-15 fighter jets. The scrapped plan was being developed by contractors at Orbital ATK and Boeing, who had been hired by the Defense Advanced Research Projects Agency (DARPA).
DARPA assigned Orbital and Boeing with the task of developing a system that would be used to quickly and cheaply launch small satellites. The system would need to be able to launch satellites with less than 24 hours of notice and at a cost of less than $1 million.
Together, Orbital and Boeing designed a rocket that would have made use of a fuel propellant called NA-7. The rocket would have been launched from the bottom of an F-15 fighter jet. The system was called Airborne Launch Assist Space Access. It was set to be tested throughout 2016.
However, early unmanned tests found that the high-powered fuel was highly explosive. Two ground tests resulted in heavy explosions, and it was ultimately decided that the dangerous substance was too volatile to be used in a piloted aircraft.
DARPA supervisor Brad Tousley said, “From a performance standpoint it’s still great but from a safety standpoint you have to work that out. As of present, we’ve stopped planning for any launches.”
For now, the team will continue to work with the NA-7 propellant because they believe that it could be useful for ground-based rocket launches. Despite its volatile nature, it is suspected that the fuel, which contains an oxidizer, could be used to simplify the process of launching rockets.
As for DARPA, it will continue to search for a safe method of quickly and cheaply launching satellites. Being able to achieve greater flexibility when it comes to launching satellites remains an important goal of the United State military.
Meanwhile, a promising effort for making rocket launches more efficient has come out of startup company Rocket Labs. The company has managed to make the turbopump of rocket engines run on electricity. By doing this, rocket engines should be able to use less fuel. Rocket Labs plans to test this engine in 2016.