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Build Your Own Cruise Missile
WegianWarrior writes "Bruce Simpson, the man behind one of the more interesting site about pulsejets on the web, has launched a project to build a US$5000
DIY cruisemissile - just to prove that it can be done, since some said his earlier
article about it was off the peg. Bruce has also designed and placed on his site a non-weld
pulsejet you can build with simple tools, a 2D airflow modeling rig and a new valve/injector design for conventional pulsejets (according to the first page on his
site, this new design is placed in the public domain)." We linked to his pulsejet pages about two years ago.
besides the obvious *geek* factor this kind of *experiments* and demonstrations should make us all stop to think a bit ...
...
how do we prevent terrorist from using this kind of stuff ?
limiting acces to knowledge (with DMCA style laws)?
creating a orwellian policial state where all are suspect ans subject to vigilance (and who controls the vigilantes) ?
limitating the publication of (now) public-domain stuff ('cause it can be used to devilish ends) ?
the RIAA/DMCA people already want to control what could go on the net, and that is, maybe, only the beggining (see China - although there 's hope there - see the massive failure of the SARS coverup) so maybe it is time to start thinking about how to mantain the net free and at the same time this planet a safe planet to stay
just my two uros,
cheers from Portugal
The impressive thing about cruise missiles is the multi-thousand mile range. That's achieved with very clever turbojet engine design, and some of that technology is still classified. Still, it's decades old.
(It's annoying that general aviation is still putt-putting around on reciprocating engines, decades after everything big went turbine.)
even military cruise missiles can't reach low orbit. That's impossible :P
Incidentally, i noticed his margin of error for targeting is +- 100 yards. YARDS, people. a football field either way. for terrorists this won't matter too much, but i imagine greater accuracy should be a primary goal.
You like your new Mac more than you like me, don't you, Dave? Dave? I asked...She said Yes.
This is spending money to keep people employed.
Cruise Missile production keep people in California, Kansas, Missouri and Washington employeed through the primary assembly and secondary assembly and R&D.
Subcontractors are scattered around the country.
Apache helicopters are assembled and tested in Arizona.
M-1 tank upgrades and factory caretaking is in Michigan.
F-15E, I, S and Ks are assembled in St. Louis MO.
JDAM kits are also made in St. Louis.
Captial Warships are built in Maine, Virgina, Rhode Island, Mississippi, Florida, Wisconson and I might be forgetting some places.
B-1B upgrades will take place in Texas and the parts are made all over the place.
In short, defense does help employment, and it helps keep blue-collar and engineering jobs going all over the country.
how do we prevent terrorist from using this kind of stuff ?
Dammit, a bunch of teenagers with box cutters have fly jumbo jets in the WTC. They had about 200 times more explosive in these jets than in one of these missiles and their equipement cost was box cutters and airplane tickets. Why would they want to build one of those missiles?
You have to solve the weakest link, not the sexy link.
Now I'm putting my aluminium foil beanie back on.
Anyway, the aircraft went through its inevitable weight growth (like software bloat when you keep adding features to a package) and it has outgrown the Williams jet engines, and they begged Williams to come up with a higher thrust version, but Williams has a good thing going with the cruise missile and said nothing doing about changing their design. Trouble is that the next tier of jet engine costs ten times as much which means the half mil price tag on the jet plane is out the windows, so I don't know what is happening.
I think while it's within easy reach to build what amounts to a large RC model powered by a pulsejet engine and guided by GPS, there are a number of issues he needs to address:
1. The pulsejet ain't going to be quiet. The motorboat sound of pulsejet engines are going to be dead giveaways of its presence. It'll be better to use a small RC jet engine with careful exhaust design to muffle the jet engine sound or a modified RC piston engine that drives a multibladed propeller so the engine runs at a lower speed to reduce engine noise.
2. A 10 kilogram warhead isn't going to do much in the way of damage, unless it dispenses a really toxic biological agent like botulin poison.
3. Guiding the DIY cruise missile is going to be a very tricky proposition. While GPS will get the missile to the general target area, the lack of the ability to avoid obstacles and to fly very low to avoid most radars means the missile will have to cruise at about the same altitude as the V-1 (about just over 1,000 meters off the ground), which means it can be intercepted by modern ground AA systems.
He didn't look into the fact that civillian GPS recievers crop the data stream if the speed gets over abour ~300mph or the altiture exceeds a preset amount (15kft?).
After his pulsejet is lit and going for a minute, he'll ahve a damn hard time driving it without any guidance information other than dead reckoning...
This is not a sig. this is a duck. quack.
Way back when I was going to university, we had a lot of unwanted guest (G-7 summit or something like that and a whole bunch of protestors). A friend of mine joked about using an RC plane to carry a home-made bomb and blow up the conference. A small group of Comp Sci and Engineer students sat down and thought about it. Our solution involved a glider (for a stealth approach) and an onboard camera (since we did not want to be near the conference). The only limiting factors we came up with (with respect to the size of the bomb) was the wing span of the glider. The bigger the span, the bigger the bomb, the easier it is to spot.
We never build it, since we did not care one way or the other about the conference (other than the fact that the protestors caused a lot of disruption to our classes), and we became scared of how easily anyone could build one of this things (using readily available parts, components and kits).
It was an eye opener of how illusionary our protection from this sort of stuff was (this was years before the Sept. 11 attacks). We realized how much our safety depended on the goodwill of our neighbours not to use something like this.
And like many posters have said before, anyone with enough education (we were all studying for Bachelor's Degrees) can build something like this, even if the information is freely available.
As a matter of fact, check out this site. GPS navigation of model airplanes has been around for at least seven years already. The only difference I see is that this guy is using a jet powered craft, and is calling it a cruise missile. Other than that, it is the same thing.
Oh, and by the way, the FAA has no jurisdiction in New Zealand.
"I'm not impatient. I just hate waiting." - My Dad
Before you say that this is nuts, think about this: helicopters are far more dangerous than any airplane. There have been a total of 21 deaths to date in U.S. commercial airplanes this year according to the NTSB. That's based on up to 150,000 flights per day.
So far, the U.S. Military, has already seen 29 helicopter deaths (and 8 additional British casualties in one of those crashes), and at least one other minor crash with no fatalities, and this is not including any that resulted from being under fire. That's based on a few hundred flights per day in Iraq, so I'm guessing a few thousand worldwide. Oh, and that's total flights, not helicopter flights. I doubt the percentage of helicopter flights is particularly high... maybe a couple of hundred helicopter flights per day as a high estimate.
That would make helicopters about 1,000 times as dangerous as airplanes. Lest you think this is a fluke of the way the military uses aircraft, the statistics on the crash rate of helicopters in Alaska should tell you otherwise. The only problem is that airplanes fly too fast for people to get a good view of what's going on in terms of ground traffic.
Enter the cruise missile. Fly ten of them around, snapping pictures and shooting video clips and periodically dumping the footage back via 802.11b networks on the ground. Near-instant gratification, and without putting your staff at risk.
Not to mention that if a blimp is cool, a missile must be... well, really cool. :-)
120 character sigs suck. Make it 250.
As you say, you could use a PIC. You can't get something as accurate as a tomahawk this way; you will have to settle for hitting a building as opposed to flying it through a window of a building. (Since GPS is supposed to be accurate to about 15 meters or so, worst case, with SA off, and most buildings are more than 30 meters in at least one dimension, hitting the building is pretty reasonable.)
The craft will of course not always be making a straight, level flight. There are environmental issues. But a course correction every second or two should be sufficient.
The GPS can deliver hyper-accurate time, and fairly accurate position. From these things one can compute one's airspeed and the direction one is heading. It is then a simple matter to determine which direction one needs to turn to correct one's course.
One would plot a series of waypoints with some sort of computer software, possibly some sort of freely available GIS package, using maps available from the USGS. Once the craft is launched it will immediately begin determining which way it must turn to head to the waypoint. The little gyro replacement will provide straight and level flight when desired. Servos are trivial to control with off the shelf hardware, like a basic stamp for example, it's nice to use a dedicated microcontroller just for servo control so you don't have to tie up your primary microprocessor doing something that silly. You could also just build some custom hardware for it since they're pulse rate (or pulse width?) controlled. It would be a relatively uncomplicated task.
Now, a tomahawk missile is capable of recognizing its target by image, and it can dodge things in its path. Obviously it has significantly more processing power than the machine we're describing. However, my point was hitting a building is easy, not flying through a window, again, as the tomahawk supposedly can. (They claim a 1 meter square hit box.) All we really need to do is follow waypoints, which we can precompute on our launch control system. As the comment above this one points out, doing so will be amazingly trivial. I suspect the poster mentioned a PIC chip because they are insanely cheap and they speak RS232 serial with nothing more than something to raise voltages, for which there are several standard solutions readily available. This allows trivial interfacing to the GPS. IIRC the Basic Stamp also provides RS232, so a pic with enough legs could speak serial to both the servo controller (at a suitably high speed) and the GPS. You only need TX and RX for each connection, because the only other connection to do about 19.2k on a good day is a ground. With four wires to the servo controller you could do higher transfer rates, or reliably get 19.2k, which should be plenty.
In other words, using GPS makes this fairly trivial. The only real defense against it is GPS jamming, since it will be small and reasonably radar-transparent to the point where if it is flying low enough the only way you will spot it is visually, and good luck to you on that front.
The next step beyond this is using radar or laser imaging to find the ground and various obstacles, and apply enough processing power to the problem to make it able to dodge trees, phone poles, aircraft (unless they're your target), and so on. That does make the problem dramatically harder, and raises the cost of the electronics by several orders of magnitude, but of course it is still within the ability and budget of the more determined and wealthy hobbyists. This necessarily means that a hostile organization with some fairly lucrative funding source, such as drugs or oil (similar compounds from a financial standpoint) could put whole fleets of them into the air.
The next step after that would be inertial tracking so that it could still operate when GPS is jammed. After that, you want to do EMP hardening, which is probably more expensive than everything else put together.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
And you think that employing people in unproductive defense jobs is not "socialism"? Socialist countries didn't pay people to stay home, they paid people to work on useless government projects. With nearly half a trillion dollar government budget for defense, the US is arguably the biggest socialist state there has ever been.
No, you aren't trolling, you just have the usual set of Republican blinders on: "Republicans aren't fiscally conservative--except for hundreds of billions of dollars wasted on defense spending", "Republicans are for free enterprise--except for hundreds of billions of dollars in government handouts to defense contractors".
Because that's what socialism is. It's the state sponsoring people who don't have jobs.
Maybe you haven't been paying much attention, but job creation is one of the major arguments for our ridiculously large defense budget: even hardware that the military doesn't want is hard to kill because representatives from those districts are worried that out-of-work defense workers will cost them reelection.
If you define "socialism" as "the state sponsoring people who don't have jobs", then the US is the biggest socialist country that ever existed, and defense employees are the biggest recipients of government handouts (followed closely by farmers). And perhaps it's time we put a stop to that kind of waste and "socialism".
I know. But you don't really need them, because you don't go around starting shit and sticking your noses in where they don't belong just because a few local rich guys want some more cash. You also have the best roads I've ever driven on. Damned fantastic, the only time they sucked was when there were crews making 'em better. Try that in the US; our roads for the most part haven't had significant upgrades since the '50s. My wife got sick while we were there on holiday, we saw several docs, no insurance, cost us $40nzd a pop. Prescription meds, around $10nzd. By comparison, no insurance up here would run you around $60-100usd, and you'd be lucky to walk away from the meds at less than $40usd. It seems to me that you may pay slightly more in taxes than we working stiffs up here (IIRC middle class down there are around 39%, up here it's probably around 30% unless you pay big bucks to a CPA), but you get a helluva lot more services for it. Smart. Me, I pay taxes so's we can build smartbombs to lob at folks who have oil that Haliburton wants^H^H^H^H Evildoers Who Hate Our Freedom (TM). Dumb.
ehintz
There is an old joke about economists that goes like this:
Economist A: "Look there's $50 on the ground."
Economist B: "Don't bother to pick it up, it's not worth the effort."
Economist A: "How can you be so sure?"
Economist B: "If it was worth the effort then someone would have done it already."
The opportunity, and probably the motive, required for the September 11 attacks has been available for decades, but it took a while for the right people to get the idea and put it into action. The possibility of building cruise missiles has only been around for a few years (cheap ones anyway). The fact that it hasn't been done yet proves very little.
There would be nothing illegal about building a cruise missile. The thing is simply a small experimental/hobby aircraft.
Legal issues would not arise until you armed the thing and used it as a weapon. Cruise missiles don't just randomly take off at self-selected targets and explode.
I've never heard of consumer GPS systems disabling themselves at high speeds and can't locate anything in the specs at the major vendors, do you have a reference for that?
Of course, it's irrelevant to the task at hand, there are plenty of GPS recievers with NAV-OUT ports that are right at home at these speeds. Plus, GPS is just the most accessible of the nav aids out there. The FAA has hundreds of beacons scattered around the country, their exact LAT, LON and ALT are published for anyone to use. Same with costal waterway navigaion beacons via the Coast Guard. And then there's simple direction finding with any commercial broadcasting antenna. (Missile: fly to the strongest radio source at this frequency (choose a station that broascasts from downtown), then circle until you run out of fuel.
Navigating via these methods is well documented, and the equipment involved could be (in many cases) cooked up at home with some wire and transistors; unlike the more complex GPS receivers and their very sensitive timing systems.
Article X: The powers not delegated... by the Constitution...are reserved...to the people
Commercial aircraft operate in a relatively safe environment.
... In this environment, the pilot's attention is OUTSIDE the cockpit. He doesn't get to look at his instruments nearly as often as other pilots. If he did, he'd run into something in seconds. Now add night vision goggles, which kills a lot of depth perception. I have a lot of respect for those rotor-heads.
Combat helicopters spend a lot of their time close to the ground, hiding behind ridge-lines, trees, buildings, medium sized rocks, tall tarantulas,
You simply cannot compare commercial aviation with combat avaition. If you want a comparison, you need to look at commercial rotorcraft vs. commercial aircraft... or some other apples & apples comparison.
I don't know if you've been in an American high school, but over here we generally make kids take a "general science" course before chemistry, biology, & physics. The one I took was complete crap, but that's more the (gym) teacher's fault... Anyways, the gernal science class should be the place where the scientific method is taught, and the other specialized classes should be for teaching the results of the method - discoveries in the respective fields in the past.