Armadillo Aerospace Flight Paves Way For Science Payloads

Matt_dk writes "Armadillo Aerospace conducted two groundbreaking atmospheric test flights this weekend with their 'Mod' vertical-takeoff-vertical-landing rocket, a vehicle familiar to anyone who has followed NASA's Lunar Lander Challenge competitions. Flying from their test facility in Caddo Mills, Texas, Armadillo Aerospace first completed a milestone flight under a NASA contract, using methane fuel and liquid oxygen as propellant. Later that same afternoon, a second successful low-altitude flight was performed using a 'boosted hop' trajectory of the same type that will be used for suborbital flights to space."

Re:Wow

[PitaBred]

I'd trust hacks from Carmack more than I'd trust some of the engineering that came from my classmates. He understands the whole system... many engineers get the math fine, but completely forget how it applies to the whole. And that makes some of the designs sub optimal at best, and highly dangerous at worst.

Video Link

[malloc]

From the Space Fellowship forum page: http://spacefellowship.com/Forum/viewtopic.php?f=23&t=396&start=1710 [spacefellowship.com]

http://www.youtube.com/watch?v=d_rqVBhwx6I [youtube.com]

Also on the SF page, a bit of commentary from Matthew Ross, including that they've internally decided on a date for LLC 2.

-malloc

Re:Story lacks all detail

[foolish]

From a post by Matthew Ross: http://spacefellowship.com/Forum/viewtopic.php?p=38466#p38466 [spacefellowship.com]

"Both of those were "LLC-style" hops where the mod flies gently up to about 55 meters and then gently back down.
Since both of those went well, we decided to do a "boosted hop," where instead of gently flying up and down, it goes full throttle for about three seconds, coasts to apogee at low throttle, falls quickly back down and then throttles up before touching down"

A 5 second serch on Wiki: http://en.wikipedia.org/wiki/Closed_loop [wikipedia.org]

"A closed-loop control system is one in which an input forcing function is determined in part by the system response. The measured response of a physical system is compared with a desired response. The difference between these two responses initiates actions that will result in the actual response of the system to approach the desired response."

So, engine generates thrust X, desired target of which is X+Y. Throttle is increased until measured response is X+Y. At which point the throttle is maintained or decreased, depending on what part of the flight profile the vehicle is in.

Re:How??

[samkass]

Single-Stage To Orbit [wikipedia.org] requires a mass-to-weight ratio in the range of 10-25. That is more than any current air or spacecraft, but recent advances in propellant storage and materials science has made it possible. Some existing rockets have been calculated to have a 10+ mass-to-weight first stage, but no one's ever tried to design the whole rocket around it. But there are certain economies of scale when you eliminate the staging as well... the rockets themselves are already heat-shielded and can lower the re-entry speeds as well. You only need 1 set of nozzles and no staging hardware. And the whole craft can be seamless and aerodynamic, allowing some steering and gliding ability without the weight of parachutes or wings.

The craft that inspired the recent SSTO designs is the DC-X [wikipedia.org], a sub-orbital prototype that was supposed to be followed by an orbital DC-Y before funding was cancelled (and the craft crashed and burned on its last flight).

IMHO, even if you put one of these things on top of an expendable booster to get it into orbit, having a partially fueled vertical lander in LEO suddenly opens up the solar system to some exciting possibilities.

Re:Hm

[StikyPad]

The armadillo can jump 3-4 feet (91-120 cm) straight in the air if sufficiently frightened, making it a particular danger on roads. [wikipedia.org]

I'd say that's definitely a sub-orbital flight.