Some California students set a series of records when their homebuilt rocket blasted to 470,000 feet at hypersonic speed in a launch from the Black Rock Desert in October. The University of Southern California's Rocket Propulsion Lab, a club made up entirely of undergrads, published a paper on the project in November detailing how they shattered records that have stood for 20 years. "This result establishes Aftershock II as the fastest and highest amateur rocket of all time," the paper claimed. The previous record of 370,000 feet was held by CSXT's GoFast rocket.
At 45-Ft long, and 330#, this rocket was about the size of a professional-grade single stage [NASA] ‘sounding rocket’.
I think it is also worth mentioning that when the rocket lifted-off it immediately began a slight/wobbly cork-screw spinning [notice the spiral smoke trail]. The cork-screw spinning, while it remained relatively stable, is a known drag factor. Perhaps if the wobbly spin could be eliminated, and a stabilization system incorporated, it would/will attain a significantly higher altitude… and would make it suitable for college science-payload lofting.
The erratic wobbly-spinning makes that a sketchy proposition. CSXT’s flight did not have this wobbly spin; and was considerably smaller at 21-Ft and also carried a camera and science payload.
IF anyone is interested, there is a freely available MIL manual on this topic [although oriented toward ordnance-delivery rockets]…
MIL-HDBK-762 - DESIGN OF AERODYNAMICALLY STABILIZED FREE ROCKETS
Dan Marotta, under FAA regulations regarding amateur rockets, they did have to get launch permission for each launch from the FAA. There is a process for that. They are limited to 150km/93 statute miles (they were just under this) and 889,600 n/s (200,000 lb/s) of total impulse. Any larger and they would fall under FAA Office of Commercial Space Transportation.
By FAA definitions, they couldn’t go much higher and still remain an “Amateur Rocket.” Amateur rockets are limited to 150,000 meters or about 93 miles. This one went up to 89 miles.
FAA can always ‘waiver’ a rule… such as altitude ceiling for an absolute record attempt… since I suspect the 150,000-m ceiling was sorta arbitrary… and probably was considered ‘hard-to-reach-anytime-soon’ by unpaid/amateurs. AND an arbitrary ceiling like this would eliminate USAF, NASA or other professional sounding rocket launch providers from claiming record after record, ad nauseum [up-thru ballistic missile high angle launches].
Of course… they could launch off of a ship in international waters… or Canada or Australia, for the FAI Absolute record.
IF the FAA is dead-set on 150,000-m max altitude, then a rock-steady non spinning rocket is far superior for the next [CSXT GF2] launch… to ‘touch the FAA ceiling’… and maybe slightly over?? [forgiveness VS permission].
BTW that wobbly spin puts a lot of stress on the structure/fins… and the solid propellant motor grain and nozzle… which has destroyed many rockets.