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Armadillo Aero One Step Closer To Space
RobertB-DC writes "The folks at Armadillo Aerospace have taken another step toward the X-Prize, dropping their re-entry vehicle from 2000 feet with no major problems noted. As usual, the Armadillo crew documented the event with text, pictures and video, and the story is also covered by Space.com (though without as many cool technical details). It's a bumpy ride, though -- instruments recorded some 10 G's on touchdown."
Now they're getting somewhere. John Carmack finally quit trying to win the prize by running at brick walls and firing a Stinger missile at the ground.
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I'm not sure how much it costs to put this thing up. But, at 10 G's per touchdown, a bunch of more of these and they may get close to breaking even!
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Is armadilloaerospace.com already down?
Here's the google cache
http://www.armadilloaerospace.com/n.x/Armadillo/Ho me/Widget`s Corner?news_id=214
We finished up all of the prep work for the vehicle on Tuesday. We welded in strapping points to hold 600 pounds of passenger sandbags in the cabin area, and we mounted five 45 pound Olympic barbell plates on a peg at the end to simulate the weight of the final engines, plumbing, and backup recovery system that will be on the full size vehicle. We mounted four 2 throat engine shells as placeholders. Total weight is just under 2400 pounds. We use a combination of multiple chain hoists, a palette jack, and a forklift to move the full vehicle around and get it up on the trailer, but we did wind up breaking one of the castor wheels that we had mounted on our tank cradle. If we wind up having to use the 1600 gallon propellant tank (the current one is 850 gallons), we arent going to be able to stand the vehicle up under the main girder inside our shop, which will be inconvenient.
On Saturday, we headed out to our test site for the drop test. There were quite a few stares on the road in transit We had a few spatters of rain, and the wind occasionally gusted to 12 knots, but we were able to perform the drop in relatively calm 6 knot winds.
Anna rented a big RV for the day, which was very worthwhile. It was nice to be able to take a break in an air-conditioned space.
5 State Helicopters arrived with a big Sikorsky for the lifting. It was very convenient that they were based close by, and didnt have a problem with our unusual application (although they did have us contact the local mayor and sheriff for explicit permission). We were very impressed with the precision that they were able to do the lifting we were afraid that the vehicle might get dragged or bounced on the crush cone, which could buckle it before the test even started, but they were able to perfectly pivot it up on the nose, and gently lift it off the ground. If we had known they were that precise, we probably could have skipped renting the forklift truck for recovery and just had them lower the rocket back onto the trailer after the test.
We made several 18 diameter test parachutes that were weighted to drift at about the same rate that the full size parachute was expected to fall. We did the test drop from 1500 AGL, under the assumption that the big vehicle would fall several hundred feet before the main chute was fully deployed. The landing point for the test parachute was satisfactory, so we planned the full vehicle drop for 2000 AGL. Neil rode in the helicopter to do the parachute releasing, and Anna hung out the side of the helicopter (with a safety strap) to get aerial footage.
We had to abort our first attempt to drop the vehicle, because the line that we ran from the helicopter to the Sea-Catch toggle release above the rocket had wrapped itself around the chain so many times that Neil couldnt pull it hard enough to trigger the release. This was fixed by tying loose loops of plastic every few feet along the chain, which kept the pull-line in place.
On the second try, the release worked perfectly. You can clearly see the naturally unstable aerodynamics of the vehicle, as it starts to tip over almost immediately after release. We all held our breath as it started to fall, but the drogue immediately inflated and started pulling the main canopy out. It was nine seconds from release to full canopy inflation. The opening shock was negligible, barely hitting 2Gs. For high altitude flights, we are aiming for a 200 mph terminal velocity under the stabilizer drogue at the time of main canopy deployment, so opening shock will be much greater then.
The wake of the main canopy is so great that the deployment drogue just rests on the canopy during descent, without any inflation at all. The real deployment system will have a much longe
Crash rated seats for military helicopters are rated to take 50G down to 20G so I wouldn't think 10G would be a problem to deal with.
Depends on many milliseconds of duration. Humans have been shown to take 35 G's for very short durations (belted head on collision at 50 mph for example), but anything over about a 100 milliseconds and your organs (and bones) tend to go a little mushy.
[RIAA] says its concern is artists. That's true, in just the sense that a cattle rancher is concerned about its cattle.
John Carmack is a semi-regular poster to sci.space.policy on usenet; he's posted several times today with details of his test plans and schedules. Even if the company site is slashdotted, go do a Google Groups search on him and the sci.space.* groups and you'll get all his publically-available info, straight from the source.
It should actually be written "10 g's", with 'g' in lower case, as this refers to 10 times the normal acceleration, while "G" the capital letter refers to something entirely different.
Visit www.scaled.com and you'll see who's going to win the X-Prize. Burt Rutan designer of the famous Voyager, the plane that made the first non-stop flight around the world.
This guy has been engineering exceptional aircraft for years. Father of one of the most radical and popular homebuilt aircraft designs ever.
J.C. has an interesting background and obviously the mind of an engineer, but no one is going to catch up with Rutan's design which resembles the X-15 project of the 1960's.
If someone at Scaled Composites is reading... Can I have a job? Yeah, like that will happen...
BitTorrent of the Video here:
p Test.mpg.mpeg.torrent
http://www.bytemonsoon.com/download.php/11286/Dro
Whenever the offence inspires less horror than the punishment, the rigour of penal law is obliged to give way...
Wouldn't 10 g's on touchdown cause death by deceleration trauma?
Bah. During the cold war, the air force did studies using a rocket sled, led by Dr. John P. Stapp that showed that 10Gs is nowhere near fatal. From the page:
I suppose the "with adequate harness" part can't be stressed enough, but there's nothing automatically fatal about 10Gs.
Dr. Stapp sounds like a pretty unique guy, and his work led to more survivable crashes in both aircraft and automobiles. I'm giving you One last chance to click on his biography, since I really want you to read it. :).