blackshire
11-07-2015, 12:06 AM
Hello All,
Recently I had posted (and I thank everyone for their replies) about monopropellants that would be safe enough to power hobbyist liquid propellant rockets. This evening I came across another monopropellant, which will power DARPA's Boeing-built ALASA (Airborne Launch Assist Space Access) satellite launch vehicle (three website links, a reprint of an article about ALASA, and attached ALASA illustrations are included below). Also:
The monopropellant that will power this unusually-configured vehicle (it uses a -single- set of four forward-mounted rocket engines to power *both* of its two stages, and the first stage is simply a "drop tank") is a mixture of nitrous oxide and acetylene. If this mixture is sufficiently tractable, perhaps it is also safe enough to power hobbyist monopropellant liquid propellant rockets. I certainly hope so, because liquid propellant rockets would offer many additional options to model rocketeers (burn times tailored to flying field sizes would be just one of these), as well as provide scale realism for models of liquid propellant sounding rockets, missiles, and satellite launch vehicles. Has anyone ever experimented with hobbyist-size nitrous oxide/acetylene monopropellant rocket engines? Below are the links, the article, and the attached illustrations:
ALASA covered on Gunter Krebs' website: http://space.skyrocket.de/doc_lau/alasa.htm
ALASA article on Boeing's website: http://www.boeing.com/features/2014/03/bds-darpa-contract-03-27-14.page
ALASA article on wordlessTech website: http://wordlesstech.com/darpas-alasa-space-launch-system-from-airplane/
ALASA Boeing article reprint (below):
ALASA (Airborne Launch Assist Space Access) is a new satellite launch vehicle concept designed by Phantom Works Advanced Space Exploration for the Defense Advanced Research Projects Agency (DARPA).
Under an 11-month, $30.6-million contract with options to build up to 12 of the 7.3 m vehicles, Boeing and DARPA intend to test the ability to cut the cost of routinely launching microsatellites into orbit by 66 percent. According to DARPA, ALASA aims to develop and employ radical advances in launch systems, leading to more affordable and responsive space access compared to current military and U.S. commercial launch operations.
The airlaunch rocket is designed in a very unusual way. The liquid fuel engines used for both the first and second stages are mounted in front of the first stage. The vehicle uses an unusual monopropellant mixture of nitrous oxide and acetylene as propellant for both stages.
The 7.3 meter ALASA vehicle is designed to attach under an unmodified F-15E aircraft. Once the airplane reaches approximately 12000 m, it would release the ALASA vehicle. The vehicle would then fire its four main engines and launch into low-Earth orbit to deploy one or more microsatellites weighing up to a total of 45 kilograms.
12 flights of the vehicle are planned for 2016.
Recently I had posted (and I thank everyone for their replies) about monopropellants that would be safe enough to power hobbyist liquid propellant rockets. This evening I came across another monopropellant, which will power DARPA's Boeing-built ALASA (Airborne Launch Assist Space Access) satellite launch vehicle (three website links, a reprint of an article about ALASA, and attached ALASA illustrations are included below). Also:
The monopropellant that will power this unusually-configured vehicle (it uses a -single- set of four forward-mounted rocket engines to power *both* of its two stages, and the first stage is simply a "drop tank") is a mixture of nitrous oxide and acetylene. If this mixture is sufficiently tractable, perhaps it is also safe enough to power hobbyist monopropellant liquid propellant rockets. I certainly hope so, because liquid propellant rockets would offer many additional options to model rocketeers (burn times tailored to flying field sizes would be just one of these), as well as provide scale realism for models of liquid propellant sounding rockets, missiles, and satellite launch vehicles. Has anyone ever experimented with hobbyist-size nitrous oxide/acetylene monopropellant rocket engines? Below are the links, the article, and the attached illustrations:
ALASA covered on Gunter Krebs' website: http://space.skyrocket.de/doc_lau/alasa.htm
ALASA article on Boeing's website: http://www.boeing.com/features/2014/03/bds-darpa-contract-03-27-14.page
ALASA article on wordlessTech website: http://wordlesstech.com/darpas-alasa-space-launch-system-from-airplane/
ALASA Boeing article reprint (below):
ALASA (Airborne Launch Assist Space Access) is a new satellite launch vehicle concept designed by Phantom Works Advanced Space Exploration for the Defense Advanced Research Projects Agency (DARPA).
Under an 11-month, $30.6-million contract with options to build up to 12 of the 7.3 m vehicles, Boeing and DARPA intend to test the ability to cut the cost of routinely launching microsatellites into orbit by 66 percent. According to DARPA, ALASA aims to develop and employ radical advances in launch systems, leading to more affordable and responsive space access compared to current military and U.S. commercial launch operations.
The airlaunch rocket is designed in a very unusual way. The liquid fuel engines used for both the first and second stages are mounted in front of the first stage. The vehicle uses an unusual monopropellant mixture of nitrous oxide and acetylene as propellant for both stages.
The 7.3 meter ALASA vehicle is designed to attach under an unmodified F-15E aircraft. Once the airplane reaches approximately 12000 m, it would release the ALASA vehicle. The vehicle would then fire its four main engines and launch into low-Earth orbit to deploy one or more microsatellites weighing up to a total of 45 kilograms.
12 flights of the vehicle are planned for 2016.