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View Full Version : Armadillo Aerospace completes the LLC1 flight profile



Larry Jacks
2007-Jun-04, 06:14 PM
From their http://www.armadilloaerospace.com/n.x/Armadillo/Home/News?news_id=346:

One June 2, we conducted a complete LLC1 (Level 1 Lunar Lander Challenge (http://www.xprize.org/challenges/lunarlander/2007/rules.html)) operational profile at the Oklahoma Spaceport. Everything went great. Representatives from AST and the X-Prize Cup were present. This was the first flight under experimental permit rules from a licensed spaceport. Both legs of the flight landed within a meter of the pad center, and our operation time was only an hour and a half.

LLC1 video footage (http://media.armadilloaerospace.com/2007_06_03/LLC1demo.mpg) (big MPEG file)

There is a point when it looks like the rocket engine cuts out briefly. This is explained on their news page:

The "engine cough" that you can see at one point in the video was actually seen a few times in the flights. It happens when the vehicle changes from a hover to a 4 m/s descent rate, and drops the throttle almost to idle to get to that rate as fast as possible. Below 10 meters, the descent rate is only 1 m/s, so we never saw that in the tethered tests. Iím not exactly sure why it seems to be more pronounced than it was on the flights at the X-Prize Cup, but the change to a regeneratively cooled engine certainly effects transient behavior. It doesn't seem to hurt anything, but I am going to probably clamp the maximum desired acceleration a bit lower in the future.

There's also a video of a tethered 192 second hover test. They believe that with a few tweaks, they can get the hover time to over 210 seconds.

The level of flight control Armadillo is displaying is impressive. It takes very precise engine thrust control to hover a rocket. As the vehicle consumes propellant and becomes lighter, you have to finely reduce engine thrust in order to maintain a steady altitude. Armadillo seems to be doing this very well.

novaderrik
2007-Jun-05, 02:49 AM
there's a spaceport in Oklahoma?

loglo
2007-Jun-05, 04:32 PM
Funny, looks like an airstrip on farm land to me. :D

http://www.okspaceport.state.ok.us/

NEOWatcher
2007-Jun-05, 04:45 PM
The level of flight control Armadillo is displaying is impressive. It takes very precise engine thrust control to hover a rocket. As the vehicle consumes propellant and becomes lighter, you have to finely reduce engine thrust in order to maintain a steady altitude. Armadillo seems to be doing this very well.
It's a hoax. You can't maneuver on a single rocket... :lol:

Actually; the footage is pretty impressive. Compared to those LM trainers, it looks extremely stable. Of course, we are talking about a boatload more automated control, but still impressive within an atmosphere.
(or should they be stable in the ideal conditions of earth's atmosphere as Bart says)

Nicolas
2007-Jun-05, 09:23 PM
Funny, looks like an airstrip on farm land to me. :D

http://www.okspaceport.state.ok.us/

Well, armadillo said they had to hurry to transform the patch they used from grown over field to test site.

Nicolas
2007-Jun-05, 09:24 PM
It's a hoax. You can't maneuver on a single rocket... :lol:


Serieously though, how does it steer? Does it have steering thrusters that aren't working visibly, or does it use thrust vectoring of the main engine? Or cg shifting?

01101001
2007-Jun-05, 10:10 PM
Serieously though, how does it steer?

Ansari X-Prize News (http://hhboard12.free.fr/xprizemay.htm#arma) (Purported to be from the Ansari Z-Prize Newsletter [Edit: looks legit; linked to by http://x-prize.blogspot.com/])


Texas-based Armadillo Aerospace has successfully tested out a new system for steering its ANSARI X PRIZE vehicle: jet vanes to deflect the exhaust from the engine. The computer controlled jet vanes allowed a small test vehicle, equipped with hydrogen peroxide engines, to hover virtually motionless above the ground for several seconds. [...] Team Armadillo is currently refitting the jet vane system to a larger test vehicle, which they intend to fly in the coming weeks.

Old news. Don't know if they continued that approach.

Larry Jacks
2007-Jun-06, 01:08 PM
Old news. Don't know if they continued that approach.

I don't know, either. Jet vanes are a simple technique but rocket exhaust gets really hot. Could you make vanes that can withstand over 3 minutes of burn time like they demonstrated in their 192 second hover test?

There are several other steering techniques that Armadillo may have used, such as a gimballed engine, attitude control thrusters (no sign of them in the video), or fluid injection. I'll try to find out how they do it. Who knows, maybe they're able to make steering vanes that are strong and heat resistant enough to withstand long burn times.

djellison
2007-Jun-06, 03:27 PM
I think the H2O2 was their old vehicle. Their new vehicle is LOx Eth - the whole engine is gimbled looking at their vids.

Doug