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Masten and Armadillo Perform First VTVL Restarts
FleaPlus writes "Recently Masten Aerospace, winner of NASA's 2009 Lunar Lander Challenge, demonstrated using its Xombie vehicle the first-ever mid-flight restart of a VTVL (vertical-takeoff vertical-landing) rocket, a critical capability for the emerging suborbital/microgravity science and passenger markets (video from ground). Not to be outdone, John Carmack's Armadillo Aerospace (winner of the 2008 Lunar Lander Challenge) flew its Mod rocket to 2,000 feet (610m), deployed a drogue parachute, and then restarted the engine to land (multi-view video showing John Carmack at the controls)."
I would venture to say that this is definitely a win for private-sector aerospace. (:
"There is a way that seems right to a man, but its end is the way of death." Proverbs 16:25 (NKJV)
Considering John Carmacks history of sucessfull rocket launcher designs we shouldn't really be suprised they managed a sucessfull rocket jump.
John's new 3d engine looks sweet. Incredible detail! Are there plans for a rail gun?
Very impressive, but these are just jump-jets for now - sort of rocket helicopters. Going from what we saw to something that can get to orbit, deposit a payload, and return to earth undamaged is going to take a lot more work. Good luck to both teams.
Bruce Perens.
to see if you can control a rocket with the WASD keys?
This gives "Rocket Jumping" a whole new meaning.
Non impediti ratione cogitationus.
Because he likes to spend time debugging his creations?
I watched it twice. In the first video I was impressed by the same thing as you, the vectoring stabilizing the falling rocket. On the second watch I was even more impressed when I realized even after the drogue shoot and free fall, the rocket landed just a foot or two from it's original takeoff point. So the vectoring didn't just stabilize the rocket, it also steered it back to the takeoff point.
Visualize Whirled Peas
Nope, first with the same engine (hence "restart"). LM landings used two different engines and stages for landing and taking off.
So how long before a corporation launches a factory into (relatively) permanent orbit, for manufacturing in microgravity and near-vacuum? Will factories like that be able to dump their products back into the ocean for collection by delivery ships?
I want to see if aerogels can be made in orbit not just cheaply, but with their internal structure oriented so they can be regular windows. They're such good insulators, and have such small mass per surface area that they could probably be dropped from orbit into the ocean without any extra packaging. Or as packaging containing other, more fragile stuff made in orbit and then the aerogel reused for its own applications once it's collected at the surface.
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make install -not war
Nope, first with the same engine (hence "restart"). LM landings used two different engines and stages for landing and taking off.
Thanks for the reminder about the separate ascent and descent stages on the Apollo LM. It's also worth noting that the Apollo LM used a hydrazine mix for fuel, which is quite handy if you want easy and reliable propellant (it spontaneously ignites when you mix it with the oxidizer), but is nasty and toxic, so you don't want to use it for an Earth-based launch where you have people nearby (or are planning on carrying people).
A simple one-shot kill weapon where you only have to aim and shoot to kill - in an instant of time, it reduces it to a 2D problem.
I am waiting for the grenades. That's where it is at baby, 4D - you got to bounce AND time them.
This issue is a bit more complicated than you think.
Pfft. Carmack doesn't use WASD, arrow keys, *or* the mouse. He has the console permanently open and controls his character's movement entirely with console commands. None of it is scripted, he's just that fast of a typist. In fact, half the time he's used timers to issue the next 90 seconds of gameplay so that he can just sit back and laugh at how predictable the rest of our movements are.
The instability was due to the dynamics of the drogue parachute, which was intended to ensure that the vehicle didn't turn upside down due to air drag before the engine lit. It did that but the length of the parachute harness ended up being such that the vehicle moved unsteadily at that descent rate.
That's a minor problem and easy to fix, with a different length harness or other aerodynamics.
With a vehicle which was aerodynamically stable going down base first, it wouldn't be a problem either. That particular test craft (and Masten's similar one) will probably turn and fall nose-first if they fall any significant distance. These are low altitude test rockets, not the final high speed high altitude models, so some problems appear with these models that will be engineered out of the final models.
You fix those short-term problems with the most cheap and reliable band-aid you can, since you're planning on a different airframe as the long term fix. The parachute was the band-aid. Not a perfect band-aid, but an acceptable one.
Given that most orbital rockets linger in the dense, friction-expensive atmosphere rather shortly and *slowly* there is very little benefit to be had by dropping them down from a plane. I suggest a simple calculation: express the orbital energy as a function of mass and height, and see how small the potential energy is compared to kinetic energy. Hypotethically, if you would lift a rocket up to orbital height without giving it orbital velocity, you'd still need pretty much all of the fuel just to reach the orbital velocity.
The only benefit from launching higher up is for sub-orbital flights that do expend a significant amount of their fuel to overcome atmospheric friction and to gain potential energy. That's why SSOne launches up high.
OTOH, LEO requires ~30 times more energy than sub-orbital. GEO/lunar requires ~60 times more. So, whatever you launch to GEO, the energy used to bring it up to 100km high is so small that you can ignore it and your error is within 2%!
A successful API design takes a mixture of software design and pedagogy.
It didn't look like they even really tried to get back on the exact spot either... just to simply get the rocket onto the pad so it wouldn't sink into the mud was good enough. Still, you are correct that it landed within just a couple of feet of the original take off point.
It will be very interesting to see what is going to happen when they try for high altitude flights. The next series is supposedly going to take them to about 100k feet, which is where the real fun is going to start. That still isn't in space, but it is getting close and will be in preparation for real sub-orbital flight.