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Inventor Building Rocket In Backyard
brundlefly writes: "Brian Walker, a toy inventor with no college degree and
almost no flight experience, plans to blast himself into space next summer in a rocket he is building in his backyard." Man, I gotta get myself a backyard!
Well, there were all sorts of "interesting" plots later on, hinged on the delightfully thin premise that they could use this rocket as a sort of super helicopter, and take off and land just about anywhere on the globe.
I recall an episode of running from Chinese soldiers through some marsh....
The show didn't live up to the movie, but then, what show ever does?
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As for seeking forgiveness later, if you launch in the wrong spot, you won't be alive to seek forgiveness and neither will the people on the plane you hit.
That said, assuming that the design is not just totally stupid, which it sounds like it isn't, I don't see why the FAA would try to stop it as long as he can convince them he'll only kill himself.
As for having all the technical challenges worked out, I dunno. For one thing, he's going to be travelling at the speed of the Earth's rotation so, while gravity may keep him upright if the engines fire with exactly the same amount of thrust, I doubt he's going to come down in the same spot he took off in (or anywhere near it for that matter). There's also the technical challenge of making all the parts work together which is never easy.
So I certainly wouldn't wanna be in that thing. But I say let him fly - he'll either make space or the Darwin Awards :)
Go Badgers! -- #include "std/disclaimer.h"
Benny Hill did a skit on this several decades ago.
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Sheesh, evil *and* a jerk. -- Jade
I could submit this to the Darwin awards even before this happens, I can tell you how it is going to end if he gets 5 feet off the ground with flames under him :)
I wasn't lost... I was only momentaraly confused of my spacial orientation relative to my prime destination.
It is rumored (or more?) that the USA has lasers that can fry satelites.
This guy's experiment isn't really applicable to satelites anyway, as his rocket isn't powerful enough to reach orbit.
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CAIMLAS
~/ssh slashdot.org ssh: connect to host slashdot.org port 22: too many beers
I wish this guy all the best. The lack of ambitious engineering in the "geek" world is depressing. Even if this guy dies in flames, as long as he make a halfway good showing, it may encourage others to attempt other, (and prehaps less umm... terminal...) endeavours in the name of science. It's great to say we (speaking for the soft handed software geeks out there) are "engineers," but the sad truth is that more and more of us have barely enough mechanical aptitude to get the screws out of our cases. While Linus and ESR never directly risked life and limb, their undertakings were just as technically ambitiuous. Large ideas, and large results can start with the "pipe dreams" of one person, especially when geek culture bands together to support the undertaking. The creative thinking a large number of us apply to code and all other things digital could do wonders if we wouldn't limit ourselves to one and zeros.
;P
'Course, I'm not exactly gonna sign up to beta test, and I hate to think of the "dumping core" joke possibilities here...
Brian Walker has no wife, no kids. No startup to babysit. Nobody that depends on him. His death wouldn't put anyone in a desperate situation ('cept himself). It may be hard on his parents, but he's 35, all grown up. In other words, he has no moral obligation not to kill himself.
:-)
It seems to me that his trip only has two possible outcomes, (a) spectacular success and (b) spectacular failure. If the rocket fails Brian Walker will be instantaneously oxidized by 7000 pounds of 90% H2O2. Which really isn't a bad way to die if you think about it.
It's rather unlikely he will suffer injuries great enough to put him in a wheel chair but small enough not to kill him. Mind you, it isn't my intent to write off the lives of the disabled, but rather to evaluate the 'regret factor.'
It is unlikely Brian Walker will regret his experience, whatever the outcome.
Seen in this light, his rocket may be very 'safe' indeed.
Ryan
Still and all, if it goes well it can only be a good thing overall. Has anyone heard anythign about the X-Prize recently? Last time I checked, they were trying to get funding to sponsor an award for the first craft that could bring a crew into space twice in like two weeks. It doesn't seem to be his goal, but this "Rocketguy" just might be on track to claim the prize if he so chose...
DO NOT LEAVE IT IS NOT REAL
There is a 10 million $ prize for the first private space shot, but you have to reach 100km.
Oh well, I guess he's not doing it for the prize anyway, but it seems like a shame to risk your life and not get the honor. I think there is some other millionare using a much more sensible approach involving a 747 boosted rocket plane.
For more information, check out http://www.xprize.org/.
For all intensive purposes, "whom" is no longer a word. That begs the question, "who cares"?
I've been interested in rockets for a long time now, and spent countless hours in OAC chem doing reaction energy equations to find the best fuel for a good home-built, *unmanned!!!!* rocket.
... or:
The most severe problem I've seen with rockets isn't deciding on the most efficient, safest fuels, but rather making sure they burn; expand; heat; react.... in a completely symmetrical way - so you can avoid pressure buildups and eventual explosions (or immediate explosions). Every documentary I've seen on rockets from German V2's to home made rockets - shows an incredible failure rate during the initial stages of developement. Failures which end in explosions.
Now my question is, would you rather:
1. swallow your tongue and choke on it for approximately 10 - 15 seconds before being incinerated in a disoriented haze miles above the earth
2. swallow your tongue and choke on it for approximately 10 - 15 seconds before being ejected through a steel casing, miles above the earth, and experience 5 - 10 minutes of your skin peeling away from your body as you plummet to the earth below through vast amounts of caustic, unreacted hydrogen pyroxide.
I know its been said, but it has to be said again: this guy has balls! (for the time being)
Ace
"Plaintiffs also contend that parachute jumping falls within the right to travel protected by the Fourteenth Amendment."
Correction: For "space", read "smithereens".
"Gromit, that's it! Cheese! We'll go somewhere where there's cheese! Everybody knows the moon is made of cheese..."
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You may like my a cappella music
...a few months ago when there was that big hubbub about the North Korean Taepo-Dong II rocket, which has a range that lets it theoretically hit an aleutian island or two. He explained that the quality of the North Korean missile program was such that it was unlikely that they could even guarantee a hit within 100 miles. He also cited Chinese rocket problems (where the North Koreans get a lot of tech) in which dozens of Chinese died on the ground from several launch accidents. As he said "Rocketry is grotesquely difficult. That is why we respectfully refer to it as 'Rocket Science.'" These aren't problems in the second stage, which is above what this guy is messing with, these are at ground level. Frankly, I admire this guy, but I hope he does more than just get his specs checked out. He needs to make sure everything is tweaked perfectly, too. Ideally, even run a test firing to make sure he's got symmetric thrust, so his rocket doesn't shoot him into the ground a mile away. I have a hard time believing he can get that rigged up for only a quarter million dollars.
Good luck, but I won't be within a few hundred yards to watch.
WARNING: there is a trojan on your
Speaking of analogies, the best one I've heard is that launching a rocket into space is much like placing a destroyer-class vessel vertically on top of a big pile of explosives, and then design the explosion so that the ship stays balanced throughout the launch, as well as preventing damage to any of the delicate control systems (AKA humans :).
ZZ
If he trusts his own design with his life I say let him do it. As long as there is a pretty low probability of bits of his craft landing on peoples homes (and since he's launching from the middle of a big desert it's a pretty low chance) let him do it. If the FAA won't let him give it a shot I hope tells them to bugger off and just does it anyway. The government control of space exploration is the single biggest reason we havn't done a damn thing since the Apollo missions ended. If you look back in history all the major exploration and discovery was done by private citizens, maybe with the sacntion or finacial backing of a government but almost never was a successful or important discovery made by a voyage planned and staffed by a government committee. A government program may have very strict safety standards, and multiple failsafes which is all nice and stuff but people should be allowed to risk their own lives trying to push the envelope of human endevor and understanding. Some will fail and pay the price with their lives, and we will mourn (and perhaps mock) their deaths, learn from their mistakes and move on. When NASA fucks up they bury their heads in the sand for several years and stay on the ground.
Now I'm not saying NASA should disband and leave US space exploration to guys in their backyard but the government shouldn't prevent citizens from trying. Ideally NASA should establish a private lauch area where private citizens can strap themselves to homebuilt rockets and try whatever they want.
"Listen: We are here on Earth to fart around. Don't let anybody tell you any different!" - Kurt Vonnegut
Home-made rocket ship
Recipe for disaster
Still safer than Mir
While I appreciate the attempt, is this post really funny? Or are you just rewarding the fact that it's writer is trying to be funny?
Moderation in all things...
**>>BELCH
Just out of curiousity, Did Wilbur and Orville have thousands of people from the top 1% of university graduates backing them? How bout that Lindbergh fella? My point isn't that anyone can do it, my point is taht neither of these groups had huge backing of the kind you're referring to, and they both did something for the first time. If his math is right, and he built it right, there's no reason why it shouldn't work. Regards, -Bouncer31-
It sure beats 42 balloons and a lawn chair.
MSK
What if he doesn't ask? If he launches from one of the many AF launch areas and has a mode-c transponder and opens a ballon flight plan at the area, the FAA won't even know about it except for TV.
Lets assume hes got 50/50 odds of getting out of this alive and knows it. Its a one shot deal. What are the fines for not playing along? The FAA is second in control of the airspace to NASA and NASA has a way around all FAA regs. In fact they have a program where you can report one offence to them and they will keep the FAA from busting you but its a one time thing and you have to make sure they know all the details so the can try to prevent thouse things in the future.
Since this is an experimental type that the FAA does not have a type class for, they may not have any control over it if he launches from military grounds (which it sounds like), the FAA may or may not have any real control over it. The military will know about it and simply block out the airspace nearby assuming its not already controlled and that will keep the 767s full of people out of harms way.
If this guy has fuel to go up 30 miles, he is not going more than 60 miles from the start if the stuff stays in a small number of pieces.
This is good.
If he succeeds, it will convince others that space is really within our grasp. It might kickoff some real commercial attempts to get there
So - if the FAA doesn't give him a license, and he blasts off into space without one, will they allow him to re-enter US airspace after he re-enters orbit?
And what kind of fine will they impose on him?
[Connection closed by foreign host]
Seriously...if these hydrogen peroxide rockets work so well, can we launch our own satellite and use it to broadcast controversial information like DeCSS or whatever happens to be under fire?
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The only way to stop it would be to shoot it down...and I can't seriously believe that ANY government would sanction such an action. The moment you open the door to intra-satellite warfare then you'll never close it. Russia will shoot down US spycams, China will shoot down "Western" media satellites...the list is ended.
Space really is the final frontier, no?
- JoeShmoe
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-- I wonder which will go down in history as the bigger failure: the War on Drugs or the War on Filesharing
http://www.rocketguy.com/rocket.html
But you are right, how interesting could a show about people being stranded on a desert island be?
Or a show about a bunch of strangers living in the same house.
Fight Spammers!
Keeping the centre of gravity of the whole assembly below the thrust point is no guarantee of heading continually upwards at all, unless the upward progress is very slow or the rockets are either controllable in direction or in thrust. As I understand it, these peroxide units are neither.
Unless the thrusts are ideally balanced, he's just going to rise up, loop back down, and crash head first. (OK, more elaborate multi-turn loops are possible as well, but you get the idea.)
"The question of whether machines can think is no more interesting than [] whether submarines can swim" - Dijkstra
Robert Frisbee, senior engineer at the Jet Propulsion Laboratory
Really. The rocket scientist's name is Frisbee?
My question is, with the financial ruin of Russia, they must have buckets of rockets sitting around without enough cash for gas. Why not just pick up one of those at the Moscow Multi-Family Garage Sale? Russia may not have the hottest safety record in space, but it's gottabe safer than a barrel of hair dye in a tube!
2 1337 4 u!
It doesn't seem that unreasonable, considering that hes not planning to actually go into orbit or anything. He wont have to worry about heat shielding or the problems with reentry that a typical orbital capsual would. If he can get the engines to work without exploding into a big ball of flaming death, I'm sure he'll be ok. Plus, I'm sure he can computer model all of this.. think what the apollo missions were able to do without the assistance of an Athlon..
Why not build a monument to the "foolishness" of the Challenger 7 rather than to their "heroism"?
It's like when The Villiage Voice did an "expose" on Biosphere II. This "muck-racking counter-cultural rag" seemed incapable of appropriating similarly jaundiced coverage to NASA in proportion to the money wasted and hubris exhibited.
Ayn Rand would, of course, have a lot to say about this, but I think it goes beyond mere disrespect for "individualism" -- it is a loss of masculinity in the culture expressing itself in a rather dishonest fashion.
As I toasted on this last Mother's day:
"Our mothers risk their lives to bring us into this world so that we may risk our lives to disobey them."
Mama's boys have trouble leaving the womb -- just as humanity has trouble leaving the planet.
Seastead this.
... it's fairly easy for the FAA to come knocking at his door and just confiscate the whole mess. If you want to pull sth like this off without the proper paperwork, you keep it secret until D-day. And you keep a good excuse ready to tell neightbors and passers-by when they ask you what this rocket-shaped thing in your backyard is...
Say no to software patents.
Sounds like "Lost in Space" meets "Sanford and Son" - now there's a remake I'd pay $9.50 to see at the multiplex!
...that we always hear about these guys when they're starting, but never when they end it? This is the aerospace equivalent of vaporware; they promise a lot but deliver very little. I can't recall how many times I've heard about people taking spaceflights "For under a million dollars" when they're just coming out, but how many of them have succeeded? You'd think that the media would jump all over any successful attempts to do so, right? And why haven't we heard about them? They don't exist. A month from now you won't remember what he planned to do, much less his name or what toys he is receiving royalties from. Rediculous...
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Does anyone remember the time motorbike jumper Evil Kinevil (sp?) decided to fly over the Grand Canyon in a jet propelled rocket ship? About 20 feet off the launch pad, the parachute popped out the back (a BAD thing) and caused a "controlled descent into terrain" as they say in the air force... He hit the canyon floor and got out alive, but just barely. I guess there are just some people who are not destined to win next year's Darwin Award!
"I figure you're here 'cause you need some whacko who's willing to stick his finger in the fan. So, who are we helping?"
You nerds.
VERY smart, considering the trip back from beyond the atmosphere is *tricky*. You have to have the EXACT angle for re-entry. If your angle is too low, you burn up. If it's too high, you bounce off right back into space. This dude is just taking an elevator up, and using gravity for the return trip.
Although I suspect he'll be screaming too much to enjoy the view, but hey - Gutsy if he goes through with it. More power to him!
-- Give him Head? Be a Beacon?
-- Give him Head? Be a Beacon? :P)
(If you can't figure out how to E-Mail me, Don't.
Or even perhaps the Illudium Q-36 Explosive Space Modulatoor
--
Sometimes it's best to just let stupid people be stupid.
...I'm not the guy who is going to have to scour the neighborhood, digging through body parts, in a futile attempt to find the jawbone so that a positive dental identification can be made.
In Victor Koman's Kings Of The High Frontier an aging rocket tinkerer called "Ace" Roberts is building a rocket in his backyard. In this book, several different non-government attempts to reach space actually succeed, but Roberts isn't one of them.
It is available for download for $3.5 on pulpless.com. Recommended!.
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Stop worrying about the risks of nuclear power and start worrying about the risks of not using nuclear power.
In a TV movie called "Salvage One" with Andy Griffith. He played a junkyard owner who got a hold of some old surplus rockets. He had a friend who did demolitions design the rocket fuel, and another friend who was a computer hacker(this was early 80's, very old school) hack into NASA and steal their navigational mainframe so they could navigate to the moon and back. His mission was to go to the moon, salvage some leftover Apollo parts, and come back. Great Movie
20% of the comments here express concern that the rocket is going to veer off course and land in either the guy's neighborhood, Kansas or some third world country.
Obviously, ya'll have never been to Steens Mountain. That part of Oregon has a population density about half of what the Gobi Desert has.
by Mike Buddha -- Someday the mountain might get him, but the law never will.
A pendulum has a pivot point, so when gravity tries to pull the center of gravity towards the earth, the linear acceleration is converted to a rotation torque around the pivot point, swinging the pendulum back down..
A rocket isn't held by anything, so the force of gravity will only pull it downwards, not cause any rotation. Gravity can't cause a rotation (ignoring very large scale gravity gradient issues), only aerodynamic forces.
Any wind will cause a rotation based on the CG/CP relationship, which will not be corrected by forward aerodynamic forces in this case because CP is forward of CG.
The truth is that I used to think along the same lines as this theory, but I built a couple models to test it, and they were complete failures.
After thinking about it for a while, I realized the difference between hanging from a pivot and having a force along the body.
John Carmack
In this case I say screw the FAA and any other groups. Launch it. It's not like this thing is that big (from the description). Load it in the back of a U-Haul truck or something and take it to a launch site.
Why can't this man risk blowing himself to kingdom come as long as he doesn't risk anyone else (that doesn't consent to it at least)? If he succeeds then he's a pioneer. If he doesn't then he's a fine rain of ash over the desert. More power to him.
Aerodynamics is my area of expertise, and Mr. Carmack has hit it right on the head. He even used the correct terminology. What aerodynamically unstable really means is that any perturbation in the flow will tend to propogate rather than be damped. It is possible for an unstable aircraft to fly, if it possesses a modern fly-by-wire system and has sufficient control authority to right itself once it has become perturbed; almost all modern fighter aircraft are designed slightly unstable. However, I don't think this vehicle will possess either.
Anyway I'm not sure where you get your number for velocity from- the only quote I saw for predicted velocity was 600 miles per hour, which is well below the speed of sound even at 100,000 feet. A velocity of 1.4 kps is roughly Mach 4.1 at sea level, or 4.25 at altitude.
At 600 mph, which seems like a very reasonable speed for this vehicle given the amount of thrust produced by its engines, there will be no shock waves. The only aerodynamic forces will be those produced by the lifting surfaces on the craft- the three large fins on the nose. There will also be drag components which act directly behind the aircraft and a thrust component which eminates from the engines (T and D generally zero themselves out by acting through the aerodynamic center). When you balance these forces and normalize them according to the length of the vehicle, you will come up with a location on the vehicle known as the aerodynamic center. If the aerodynamic center is behind the center of gravity, the aircraft is said to be statically stable and will therefore fly straight, righting itself after perturbations occur. This design is most likely statically unstable, because its aerodynamic center is (painfully obviously) well ahead of its center of gravity. Think about an arrow: it flies straight because it has a cg near the front and an ac near the rear.
At M=4, you are correct that breezes are orders of magnitude below the pressure differential caused by a strong shock structure. The static pressure behind a normal shock would be 18.5 atmospheres! However, this fact is largely irrelevant, since the shock structure won't -ever- be perfectly symmetric. An asymmetric shock structure will produce regions of differing static and dynamic pressure behind the shock. This will manifest itself as a powerful force applied approximately to the nose of the vehicle. The rocket will then begin to rotate about its center of gravity, and the pressure force will tend to increase as the rocket begins to rotate because the angle of attack increases the pressure difference (through various means). The only way to solve this is to move the ac back as far as possible, preferably by adding fins near the rear of the vehicle. It can also be done with thrust vectoring.
:endresult
The end result at either mach number will be a spinning projectile which eventually tears itself apart due to the propellant chambers experiencing accelerative forces on non-loadbearing walls.
If by some miracle of engineering this does not occur, he would still (probably) not survive sustained flight at Mach 4 in this vehicle. The ballistic coefficient of the nose appears to be too low, which will cause a concentration of aerodynamic heating at the tip. I really can't tell for sure from the picture, but hypersonic vehicles are generally designed with blunt noses so that the wave detaches from the body, allowing the heat to dissipate. If it stays attached there will be a small region in which a layer of incredibly high entropy develops which will cut through steel like a knife through warm butter. For more details, search the web for pictures of what happened to the scramjet NASA tried to hang from an X-15 in the 60's.
FWIW a (statically stable!) titan IV experienced rotationally induced structural failure early in the program when an engine malfunctioned, causing the rocket to become unstable. It is an incredibly important concept that Walker seems to have completely overlooked.
Don't get me wrong; I hope this guy succeeds. I really, really do, partly because I admire his courage and tenacity and partly because it will provide an immeasurable benefit to space privatization advocates everywhere. Since I am an aero type, I stand to benefit tremendously from explosive growth in that sector of the economy. Unfortunately, he won't do it with this design, which makes it exceedingly frustrating-- because it really isn't that hard to design a rocket to do what he wants to do...
Rev Neh
... and there is no doubt, that one day he will be
where the eye of his telescope has already been
Did you see the pictures of the rocket? It looks like something that Marvin the Martian from the cartoons would be flying!
Remember that this guy is using the royalty money from his toy inventions to do this. He's a toy inventor. Why would we expect his rocket to look like anything but what he's good at?
Juan Ho.....A chinese daredevil way back in some B.C. century I read about once. In order to fly to the moon, he strapped a buttload of fireworks to the back of his chair, lit the fuse....and Juan Ho was never seen again!
>>>>>> Chewie, take the professor in the back and plug him into the hyperdrive.
It sounds like this guy hasn't done much real-world testing of rockets of any kind. The article didn't mention any tests of full-sized mockups of the capsule to see if the damn thing will fly right. His propulsion system seems to be pretty simple, but there are still many things that could go wrong along the way.
I know I wouldn't risk my life on an untested design, especially one made by someone who seems to have no experience at all.
One other thing is that the FAA tends to be fairly bitchy about high-powered/amature rocketry using tested and certified componants. He'd have to do quite a bit of legal wrangling to get permission for this.
--
Soma: because a gramme is better than a damn.
In the words of Keanu - "Whoa."
,
faeryman
At first I thought it was just bad reporting, with "Most of the weight will be behind, and gravity will keep the rocket pointed upward", but seeing the picture on his site backs that up.
Putting a big, fin-looking cockpit ahead of the fuel tank mass is going to make every breeze cause a heading change.
His site goes on with:
"What about guidance systems? The thrust will come out at the top of the rocket. An early American pioneer Robert Goddard did the same thing with his early test rockets. The rocket should "hang down" from the thrust like a pendulum"
That DOESN'T WORK.
It doesn't matter if a rocket is being pulled or pushed, all that matters is the relationship of the center of gravity to the center of pressure.
The reason why the intuitive "hangs like a pendulum" doesn't work out is that gravity acts on a deflected pendulum in a direction out of line with the pendulum string, while a rocket thrust will always be in line with the body.
John Carmack
Will there be lawsuit for this guy taking their idea?
Fight Spammers!
I have a soft spot for obsessed and brilliant people. My hero used to be Simon Jansen, the guy who is working on redoing the entire original Star Wars movie as Ascii art animation.
Brian Walker now has Jansen beat hands down. I the obsession department, he reminds me of the Aleut character in Snow Crash, who's such a badass that nobody else has to worry anymore about trying to be alpha badass.
The interesting thing about Walker's inventions is that he is clearly pretty canny about knowing exactly how crazy to be. For example, his homemade sub is really a kind of submergeable manned keel that dangles underneath a small motorized catamaran -- enough to give you the experience of being underwater without all the complexities of a free diving sub.
I personally can't help but admire somebody with this kind of persistence and creativity. Here's quote from him:'"The one thing I've done more in life than anything is failed," he said. "I've failed and failed and failed and failed and failed and failed." ' But of course he kept going and had made a bundle with his toy inventions.
The rational part of my mind tells me that Walker's going to blow himself to tiny bits, or plummet into the ground at multiple mach speeds as all the escape latches are jammed by aerodynamimc pressure. But jeezus, you've got to admit he's got balls to try something like this, and not just because he's facing death. This thing will either be an unspeakably humiliating failure or an indescribably glorious triumph -- there's no middle ground.
If he succeeds, I hope they make a movie of this. The only way it could get better is if somehow parlays it into some nookey (unfortunately, in my experience real women aren't impressed by this kind of thing, at least not from a passing on the genes standpoint).
Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
That looks like one of those eight inch long styrofoam airplane toys that you buy for a couple bucks at the toy store and launch with a plastic stick and rubberband.
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seumas.com
All forces acting on a body can be summed to a vector through the CG and a rotation around it.
The thrust coming out at the nose or tail doesn't matter, it will still act through the CG.
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R !
!
!
!
CG
!
With a rocket exhausting down from R, there will be both an upwards acceleration and a clockwise rotation. That obviously won't fly straight.
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R ! R
!
!
!
CG
!
With two rockets (or any symetric number), the rotational forces cancel out, leaving just a forward acceleration acting through CG. Again, no matter where the forces are applied to a rigid body, they act through CG.
This rocket will fly straight in an airless vaccuum, or in a perfect world with non-moving air and EXACTLY balanced engine thrust.
When a body has a center of pressure that isn't exactly at the center of gravity (almost everything but symetric and uniform blocks of material), a sideways gust of wind will cause a slight rotation of the rocket around around CG.
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R ! R
!
!W
!
CG
!
If a wind force acts to the left at W, it will cause an acceleration to the left through the CG and a counter-clockwise torque around CG. The existance of other forces on the same body have no effect whatsoever on this. The rockets don't thrust "down" (which WOULD cause a corrective force), they thrust "along the rocket".
A "stable" rocket will have the CP behind the CG, which causes the much larger forward aerodynamic forces to swing the rocket back towards it's direction of travel. That's why there is a minimum stable launch speed for unguided rockets -- the forward aerodynamic forces have to be larger than the sideways winds.
An "unstable" rocket with CP ahead of CG will fly straight as long as there are no winds and it is pointed exactly in it's direction of travel. As soon as there is a slight rotation, the forward aerodynamic forces push it in the same direction as the existing disturbance, reinforcing it into a rapid spin.
Direction of travel determines the orientation of CG and CP. This rocket will be stable when falling down, just not when flying up.
Again, the pendulum is different because it is not a single rigid body. If you didn't hook a bendulum to anything, it would fall without any rotation in an airless space, and would fly with it's CG (the ball) ahead of it's CP if thrown.
John Carmack
This is going to be the craziest bleach-job known to man.
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seumas.com
Actually, I don't see a single reason why this can't be done, according to the research I've done by watching hours and hours of cartoons.
My findings show that one of the most popular techniques involves using a giant slingshot.
Phallic Symbols in LOTR
Or maybe he'll end up like Lawn Chair Man except floating at 30+ miles up instead of merely 16,000 feet. Let's hope he calculates the amount of fuel he needs, successfully. And, at least he is seekng FAA approval first.
ByteMyCode.com: A Web 2.0 code sharing community.
I'm reminded of DD Harison from Heinlein's 'The Man Who Sold the Moon' I certainly hope that he can pull this off. We need to have private citizens able to get off of the planet before we can see private spaceflights become a true reality. I think that between this, and the man going up to the MIR space station, the true privitization of space flight.
On the other hand, if this guy ends up just being a crack head who wins a Darwin Award, it'll probably have the same effect on private spaceflight that the Challenger did for American Space Flight. Hopefully, This will be seen in the history books as the thing that set off the great private space of the early 21st century.
Hopefully, this man will be able to get his ship up even if the government says no... He can try to take it out of the country, or just do it any damned way.
Here's to hoping...
Actually from my extensive cartoon research I have determined that on his first attempt he will either:
a) Leave the parking brake on, preventing him from going anywhere or...
b) Put the darn thing in reverse, driving him backwards into the ground approximately half the length of his ship before he corrects the problem and blasts off properly.
So far I've gotten all my Karma from telling people they are wrong... :)
You can find more details this guy and his inventions at his website. He is apparently currently in Russia undergoing Cosmonaut training.
There is no doubt that this guy has far too much time and money on his hands.
-- David Smith
C:\ is the root of all evil.
On the one hand, if you think about it, Mr. Walker not really breaking any new ground, here. He's established some reasonable milestones, not quite as lofty as the first US venture into space. He's using "off-the-shelf" parts to build his vehicle. The technical breakthrus required to achieve a trajectory peak of 30mi is some 40 years old.
I remember back in da' Day when I was studying to be a *real* engineer. <grynn> The theory to achieve what Walker is aiming for is understandable and appliable by a 3rd year BS Aerospace Engineering student.
My concern would be that $250K seems pretty light, even for the limited scale of this *MANNED* rocket (and required flight systems). I recall projects in college requiring larger budgets for the design and building the of systems to launch and control unmanned vehicles. Seems to violate the first rule of engineering - make sure you leave PLENTY of margin for error.
All the same, if he *does* do this without turning into human crater residue, I think I will have a new hero. Got to admire a man who sets his sights on something in childhood, and works tirelessly for decades to achieve it.
...anactofgod...
<Crush your enemies. See them driven before you. Hear the lamentation of their women.>
---anactofgod---
"Equal opportunity swindling - *that* is the true test of a sustainable democracy."
I like his plan a lot, its very daring and dangerous but is feasible, I'm sure the cynics are just jealous they don't have the cash or balls to pull this off.
This was in memepool several days ago.
-p.
Subj: Tornado Shelter on Launch Day
'Cause, reading the article, the guy looks like he might actually get off the ground. (FAA may or may not be the only sticky point.)
I'll bet money that this will end badly for both him and his neighbors.
In fact, I'd go so far as to suggest that:
He gets off the ground.
Reading into the article, he's got very little, if any, navigation controls. He goes where he goes.
On launch, he's going to point away from the Pacific, so that he doesn't land in the middle of the ocean. (Without support choppers and stuff like Apollo and other early space travel had, that's certain death.)
At the calculated speeds, wind shear and other things on launch and descent will be more and more critical variables, and far less predictable.
He could end up coming down at a high rate of speed into a Kansas dooryard...
Therefore, I'd advise the use of cellars and tornado shelters on launch day.
And yeah, may as well pre-engrave his name into the Darwin Award trophy. It's a safe bet that the engraving won't be going to waste.
Fire and Meat. Yummy.
I'm not sure I agree that it's actually so terribly smart of a thing to do. I mean, the guy is planning on going 60 miles into the atmosphere. NASA supposedly defines space as starting at 62 miles up. What happens if his already rough-sounding calculations are off by a couple of percent, and he ends up in space for real?
Dude, Earth's atmosphere gets gradually thinner as you go up. It's not like somewhere between 60 and 62 miles, you break through this "membrane", and then smash into it while you're trying to get back down.
I mean, really. That's a weird concept of "space". You do know that the air gets to thin to breathe on top of mountains, right?
In conclusion, this guy will die, but not because he overshoots his target by one mile.
"Beware he who would deny you access to information, for in his heart he deems himself your master."
Theoretically, if you dug a hole to China and jumped in, you would accelerate all the way to the center or the earth and start decelerating on the other half of the trip, and end up coming out in China at the same speed as you went in, theoretically. I wouldn't want to get stuck oscillating back and forth from China to North America. This would be very cheap travel (and if I was apt to grab a calculator, I could calculate the travel time). However, you would burn up before you even got near the center. :)
I think this dude is gonna be winning a Darwin Award pretty soon.