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Carmack's Armadillo Aerospace Rocket Crashes and Burns
mcgrew (sm62704) writes "New Scientist is reporting that John Carmack's 'Armadillo Aerospace' has suffered a large setback in the Northrop Grumman Lunar Lander Challenge after one of its two main rockets crashed and burned. 'During the test, Texel lifted off and hovered without incident, then descended again and touched the ground. But it then rose again unexpectedly and began accelerating upward. "Crap, it's going to fly into the crane, I need to kill it," Carmack recalls thinking. He hit the manual shutdown switch, turning off the vehicle's engine in mid-flight. Texel was about 6 metres above the ground and fell like a stone. One of its fuel tanks broke open when it hit the ground, spewing fuel that ignited and engulfed the vehicle in flames. "It made a fireball that would make any Hollywood movie proud," Carmack says.' No one was hurt in the crash, but the vehicle was destroyed."
Gravity will make you it's bitch!
"It is a miracle that curiosity survives formal education." -Albert Einstein
On one hand what they were working on was completely destroyed, on the other the explosion was AWESOME!
"I use a Mac because I'm just better than you are."
...anisotropic filtering.
My blog
This is a good thing. It proves (again and again) that new technology is never perfect. Just think, no computer program is ever completely bug free the first time it's compiled. The first car is never perfect... There are always bugs in any system. The point is that the safety mechanisms in the system worked well (after all, acording to the inputs of the lander, it was falling). As with any "accident", there are many failures that lead up to those incidents. That's the price of achievement. Nobody was hurt, so learn, build bigger and build better. If you learn from it, it wasn't a "mistake"...
If a man isn't willing to take some risk for his opinions, either his opinions are no good or he's no good
Always ensure you have enough HP to survive the landing or an invulnerability artifact when performing a rocket jump.
Unpleasantries.
It was a bad weekend for Armadillo. We set out to put some flights on Texel, the backup Quad vehicle, and it didn't go so well. We have video that we will be releasing, but Matt had to leave for Germany the next day, so it won't be digitized for a week and a half.
We started out with a normal 90 second elevated / tethered hover test, but we ran into a problem with the actuator power. We initially thought it was a bad main power switch, but it turned out to be the lithium-polymer battery pack cutoff circuit incorrectly shutting down at 16 amps of load instead of 40. This was a new battery pack ( www.batteryspace.com HPL-8059156-4S-WR), and it had passed all the individual actuator checks, but when the igniter started firing with both high amp NOS solenoids, the battery shut down (went to 0.3 volts indicated) after one second and stayed there until it was physically disconnected. Russ made a fairly heroic field repair, cutting open the battery pack and wiring around the protection circuit while sitting on top of the rocket. The total time spent on this after three attempts was 90 minutes, and enough lox had boiled off that the vehicle hit lox depletion at 60 seconds of flight. We got a few good data points from this: the batteries need to be checked at full current load, with vents open we boil off about two pounds of lox a minute, and lox-depletion runs are benign, if a little flamey.
For the second flight we were going to do a ground liftoff (still tethered for runaway protection) to test the automatic ground contact engine shutoff code. We have had several reasons to want to automate this: We get a fair bit of bounce on touchdown, because the engine is essentially keeping the vehicle weightless during the terminal descent. A computer controlled shutdown would be at least a half second faster than my manual punching of the shutdown when I visually see ground contact. The quads will just safely bounce around on the ground a bit if the engine just goes to idle and doesn't shut down, but the module, with the gimbal below the CG, will try to tip itself over when a landing leg becomes a pivot point, so there is extra incentive to get it shut off fast. You can see that in our XPC '05 vehicle flight. We also need to handle the case of the vehicle landing in a situation where I can't shut the engine off promptly, either because there was a telemetry problem, or when we are doing high altitude flights, it lands out of direct sight. There is a separate shutdownTime parameter that will keep it from sitting there at idle for ten minutes, but a telemetry abort could still have it on the ground and cooking for the better part of 220 seconds. We could still shut the flight safety fuel valve, which would result in just idle level lox pouring out of the engine, but that has its own problems.
I have been very hesitant to put in ground contact shutoff code, because shutting the engine down for some incorrect reason would be catastrophic, and I would feel awful if that ever happened. We had some switch based ground contact sensors on the old VDR, but they never got tested. We have concluded that the landing jolt, as seen by the IMU accelerometers, is a good enough ground contact signal. There is always the worry that combustion instability, or a nozzle ejection event, might trigger the signal level, so there are additional guards about it only functioning when you are within three meters of the ground (we must leave some slop for uneven terrain or GPS innacuracy) and trying to descend.
We loaded up again, being very thankful that we now pack three six-packs of helium for each test trip after we were forced to cancel the second flight on a previous test session due to insufficient helium after troubleshooting a problem forced a repressurization on the first flight. Liftoff and hover was fine, and at the 45 second mark (no sense pushing it on a ground liftoff), I had it come in for a landing. It hit the ground, and I saw it bounce back up. My first thought was "That didn't seem to help at all".
Sometimes it's best to just let stupid people be stupid.
And to think, they want us all to ride in these things commercially....
Actually, this is exactly why John and company will be successful. The biggest problem with modern aerospace is "paralysis by analysis". They're so afraid of crashing anything that they have to produce (sometimes literally) millions of pages of documentation before they actually put something into the air.
Armadillo learns by *doing*, not just by creating paper studies. When they're ready to put humans in space, you can bet that their ships will have had hundreds of test flights.
Sometimes it's best to just let stupid people be stupid.
From John's post to the Amateur Rocketry list :
We have video that we will be releasing, but Matt had to leave for Germany the next day, so it won't be digitized for a week and a half.
So, it's coming, just not released yet.
XenoPhage
Technological Musings
So they're not there yet. Big deal. Armadillo's attitude to safety is that it's ok to risk the vehicle in testing, as long as people aren't at risk. They do a *very* fast development cycle, and they don't pretend to be able to find every problem through analysis -- which means some of them get found the hard way. That's a *good* thing for safety, not a bad thing. You *can't* find every problem through analysis, even if your budget is 5 orders of magnitude larger than Carmack's and you try.
Carmack's approach is to treat the vehicle as a developmental test platform, and that involves a certain level of risk to the vehicle and acceptance of that risk. The result, however, is that he learns things a *lot* faster than he otherwise might, and as a result the entire development program is faster and cheaper, counting the cost of the lost vehicles.
When Carmack shifts the vehicle from developmental status to operational testing status and then to operational status, I'd be happy to trust him when he says it's safe. It's unfair to criticize him for being unsafe now -- crashing the vehicle wasn't a safety risk!
Failed? I think not. Just so you're aware, Armadillo was the only team last year to even attempt the lunar lander prize, and except for some bad luck, would have walked away with it.
This year, there may be a few other challengers, but I think John and company will walk away with it. John and his team have taken this challenge in directions that the "big guys" have never tried, and it's working.
We'll see! Only 65 days left!
XenoPhage
Technological Musings
Id say so.
Or, put another way... within 20 years of the Wright Brothers the airplane industry had far better safety records than the space industry does after 50 years.
Engineering is the art of compromise.
When I was a kid, I remeber the coming of the 747 (I paid attention since my father was a commercial pilot). Many ppl swore up one side and down the other, that this was a NIGHTMARE in the making. They said that they would never go because it would crash all the time killing more ppl than were in my town (small town). Their were so many cowards and small thinkers. Fortunately, Boeing pushed it, built it, and now, it is the major largest craft going.
Another group thought that we had no business going to the moon and swore that LLM would simply sink into the moon. I suspect that these same ppl believe that we never went.
Just so that you know, Carmack and his rocket are real.
I prefer the "u" in honour as it seems to be missing these days.
I have no opinion on Carmack one way or another, but tagging this story with 'haha' and 'hesnorocketscientist' seems a tad mean.
So he's a game designer dabbling in space exploration. It's not like he ran a bicycle shop or something. Now *there's* a logical starting point for a career in aeronautics!
"Only two things are infinite, the universe and human stupidity, and I'm not sure about the former."
This was how soviet was testing their rockets, by trial and error. They launched a prototype and then they looked how it flew and why it blew up if it did. Saw a documentary about soviet rocket engineering and in it some nasa guys said it was one of the mayor reasons why soviet was greatly ahead of USA in rockets.
Texel was one of two essentially identical vehicles that Armadillo put together last year for the Lunar Lander Challenge. The other is Pixel, which is the one they actually flew last year (and that had a good shot at winning) at the LLC level 1 event. Pixel is still flightworthy. This crash of Texel doesn't take them out of the LLC race, although it will lower their chances of success; it is going to make them much more cautious about banging Pixel up ahead of the next LLC competition and therefore they'll get flight less testing in.
They're also working on a set of new vehicles they call Modules, of which I gather they have one essentially complete and five in production.
With reasonable men I will reason; with humane men I will plead; but to tyrants I will give no quarter. -- William Lloyd
Shame, I was already to invest in his new company, dubbed the "Union Aerospace Corporation"
You mean even safer than a huge orange fireball?
I don't know, that's a pretty high bar.
I'm hesitant to criticize a group that is breaking so much new ground so quickly, but this sounds like some really amateurish mistakes when it comes to electrical engineering. Basically they added new sensors to detect when the craft impacts the ground. The computer monitoring the sensors was expecting a signal of a certain strength to indicate it had touched the ground, however the value the computer was expecting was higher than what the sensors could physically produce. So it sounds like they either engineered the electronics wrong making it impossible for the sensor to produce a meaningful response, or they misread the sensor datasheet which resulted in flawed software.
Now it's one thing to make an engineering mistake, but it couldn't have taken them an hour to rig up a simple test rig they that they could drop onto the ground, or tap with a mallet, or something similarly simple, to see if the computer could register a landing.
I just can't imagine strapping something new onto an entire rocket assembly, going to all the risk and expense to actually launch the thing and fly it around, hoping that all the new circuitry and software will work perfectly the first time.
It makes me wonder about the whole process NASA has in place with these contests. Even if a craft can meet various flight goals, does it result in anything of worth to NASA? For example, take a piece of software. Say there is this program that really does something impressive (game engines come to mind). So you take a look at the source, and find it is a total and complete mess. Maybe it is full of memory leaks and other bugs, so it just can perform a specific task right, but given other scenarios it crashes. Maybe the code is insecure, or is not scalable, or cannot be extended, or is not maintainable, or is not portable to other platforms. Any of those things could practically render the sources useless. But yet the program does a specific task and does it really well. For some reason I feel that NASA is going to end up with crafts with similar engineering caveats.
Dan East
Better known as 318230.
This evolutionary path is yet to be walked down.
You know what, this is one area where I prefer intelligent design!
(I know, I know, I have sacrificed my principles for a cheap joke..)
"A nation that forgets its past is doomed to repeat it." - Churchill
So if you die building and testing rockets for the government, that's noble -- but if you die building and testing rockets for a private company, that's ignoble.
Bullshit.
Advancing the state of the art is a noble cause no matter who pays the bills -- whether it's the taxpayers as a whole or a few millionaires who want to go on expensive vacations, working on spaceflight is a just and honorable vocation. To the extent that this research -- whatever the immediate funding source -- helps to bring down the cost of launching payloads into orbit in the long term or leads to the use of less expensive, reusable launch vehicles, the people involved in it are doing something they can legitimately decide is an activity worth risking death over.
Legislatively restricting spaceflight to governments in the name of protecting those people who may otherwise voluntarily choose to work in a field which they know has more risk than some desk job is an example of the worst sort of "mother-knows-best" nanny state bullshit governance. You can have your safe office job if you want it -- but don't you presume to speak for my interests when you lobby against letting me choose to work on something more interesting and useful to humanity as a whole than 99% of the population has any opportunity to be a part of.
Exploration for profit has a long and proud history -- what do you think brought Columbus out of Spain? The profit motive makes the work itself no less worthy of respect.
You see, we're all volunteers at Armadillo, and therefore all have day jobs. My day job required me to come to Germany for the Leipzig Games Convention to promote things entirely unrelated to Armadillo. This is the job that actually provides a salary, so it kind of takes precedence over Armadillo sometimes.
Could I have left the video with the others so that they could capture it and get it up on the web page? Well, no one else on the team has any experience with that -- their expertise is in software design, electronics, manufacturing, welding, etc. So I'd have had to train them to do it. And again, why would I do that when, as I understood it, John's not going to post the video till the next update anyway?
But you go and believe whatever you want. Just know that we WILL post the video when I get back.
Matthew Ross
Armadillo Aerospace