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Toys

11-Pound Model Plane Vs. The Atlantic 164

merrell writes: "Apparently some model plane builders are going to send some balsa wood loaded with some tiny computers and GPS receiver across the Atlantic, running on less than a gallon of gas. The Washington Post has an article on it. Just goes to show what some retired NASA engineers with lots of free time can do. :)" If this was a movie, it might sound too unlikely.
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11-Pound Model Plane Vs. The Atlantic

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  • by Anonymous Coward
    Weight? Isn't 11-pound the price?
  • by Anonymous Coward on Sunday April 29, 2001 @01:22PM (#257923)
    Now it is possible for individuals or small groups to build private cruise missiles. Think of a high tech version of Black Sunday... or imagine what would happen to the United States if someone flew a 1000lb pilotless bomb into the 2002 Oscars!
  • by Anonymous Coward on Sunday April 29, 2001 @07:28AM (#257924)
    or if it flies too high, it'll get burned by the sun!
  • by Anonymous Coward on Sunday April 29, 2001 @07:32AM (#257925)
    "And then we added a few pounds of high explosive and changed the final co-ordinates to something more interesting." Wonder what the waypoint accuracy of this thing is? Dropping bombs down airshafts not just for the USAF anymore! Wheeeee!
  • by Anonymous Coward on Sunday April 29, 2001 @07:51AM (#257926)
    Of course that begs the question: aren't we lazy enough already?

    Ha, a good engineer will go to any amount of effort to avoid extra effort.

  • by Anonymous Coward on Sunday April 29, 2001 @07:57AM (#257927)

    ...now the Chinese are going to get our balsa technology.

  • by Anonymous Coward on Sunday April 29, 2001 @08:11AM (#257928)
    Balsa isn't strong...yeah right. You are right, it's not strong. Strength comes from engineering. In a high school Odyssey of the Mind competition, we build a struncture out of balsa, and super glue, that weighed 8 grams, and held in excess of 500Lbs. We used all the weights availabe, and it still did not break. We tried an experiment on our own, and found that it held 800lbs for 10 minutes. 10lbs/gram! Our play sucked balls, and we lost to a group who had some big chested girls. So much for Odyssey of the Mind!!!
  • by Anonymous Coward on Sunday April 29, 2001 @08:14AM (#257929)
    The mylar they are using is pretty impervious to weather. My son lost a R/C plane in a corn field, and we didnt get it back for almost 3 months. It had survive pretty well except for the radio equipment. They say they are using camp stove fuel, which means they are probably using a 4 cycle engine, and an ignition system. A 2 cycle engine does not have the fuel economy that is needed for this. Also with the ignition systme, they are getting telemetry for the engine RPM.
  • by Anonymous Coward on Sunday April 29, 2001 @09:48AM (#257930)
    Check out this!

    http://www.insitugroup.com/LaimaFlight.html [insitugroup.com]

    This plane was a little bigger, and made mostly out of carbon/epoxy composites, but it weighed 29 lbs and flew trans-atlantic on a gallon and a half of gas! The first unmanned trans-atlantic flight ever!
    The University of Washington Aero/Astro department is trying to build one to cross the pacific first too, but those guys at the air force beat us to it. Of course, their budget was MUCH bigger than ours.... Our airplane is only 50 lbs and 6 feet long!
  • Hey...given the speed of this thing, the goverenment should use it for SDI testing...they might actually have a target they can hit!
  • Yes, they make a perfect delivery system for a terrorist. Zero cross section on radar, silent, incredibly hard to see, and they can carry a decent payload. Help me out here. I don't stare at O-scopes for a living, but wouldn't these things give some kind of radar return? I don't know if wood and Mylar would absorb, reflect, or transmit radar-frequency RF. But if we're talking about relatively sophisticated, modern radar, I don't think that's the whole story; there's more to detecting an aircraft than getting a "skin paint" off the wing and fuselage surfaces. For modern aircraft, radar-return design considerations include things like how visible the jet engines' impeller blades are to radar waves. To some extent the internals of an aircraft can reflect radar waves, causing a return, if the radar energy isn't dissipated or "trapped" using stealth materials and design techniques. The avionics, payload, engine, and prop at least would have some characteristic, if significantly small, signature, right? I'm thinking that in conjunction with computers that do image analysis, they'd look somewhat different from a bird -- at least in flight behavior, if not radar cross-section itself. I gotta admit, though, the image in the mind's eye is hilarious: swarms of these things, each carrying 10 kilos of pure cocaine or heroin, cruising serenely past a DEA aerostat in the dead of night....War On Some Drugs my @$$.
  • by Kit Cosper ( 7007 ) on Sunday April 29, 2001 @07:39AM (#257933) Homepage Journal
    I remember reading the account of Maynard Hill's 33 hr. endurance flight in Model Aviation magazine when I was a teenager. It was amazing at that time that anyone could keep an airplane up for that long. The biggest surprise for me is that it's taken around 20 years for them to make this attempt. :-)

    --Kit
  • Ah, but he puts more effort once into avoiding the work, so then he can avoid the work again and again and again and again and...
  • To pull this off, I would think that they are going to rely on favourable wind conditions. With a maximum airspeed of 45 mph, even a 15-knot headwind (which not much more than a breeze, particularly at 2000 feet on the open ocean) halves their ground speed and thus halves their range.

    IIRC, there is a prevailing wind that should ensure them a good chance of tailwinds for this trip - the same prevailing winds that people use for Atlantic balloon crossings.

    Go you big red fire engine!

  • Fat chance, buddy.

    I'm sure the security guards at Area 51 are equipped with full-automatic weapons, and with nightscopes and modern M16A1's that model airplane you're suggesting will be blown to pieces from all the small-arms gunfire.
  • However, given the fuel consumption of those little turbine engines, unless you can build a plane to be mostly a flying fuel tank you'll be lucky if you can fly it more than a few miles.

    That's why modern jet airliners have fuel tanks that carry fuel in the thousands of gallons.
  • by RayChuang ( 10181 ) on Sunday April 29, 2001 @02:01PM (#257938)
    Given that the accuracy of satellite GPS is under 30 feet nowadays, the frightening thing is that anyone that knows how to make nerve gas (if you can make insecticide you can make nerve gas) could build a GPS guided model plane filled with 1 kg of Sarin, which when dropped would kill everyone within a 250-300 feet radius of the release point in open air. You could literally fly one and drop it off in front of the New York Stock Exchange. (shudder)
  • by MikeFM ( 12491 ) on Sunday April 29, 2001 @08:35AM (#257939) Homepage Journal
    Did you see that Junkyard Wars (TLC show where people build groovy gadgets from spare parts and compete the gadgets against each other) where they built the gas-effecient vehicles? Now that was impressive.

    I've been looking at the Honda Insights because they get around 70mpg which I think is impressive but yeh 3000mpg just blows that away! To bad I'm to big to sit on a model plane. :)

    At a recent LUG meeting we had a guy from our Universities solar car team give a talk and he mentioned that some people have built motorcycles that are entirely solar powered. To me that would be the best. I'm seriously considering trying to build one for myself. Has anyone experience in such things? My biggest question is the legality of driving such a thing on the highway. It'd be awesome to take roadtrips and never have to buy gas though. :)
  • by HeghmoH ( 13204 ) on Sunday April 29, 2001 @07:34AM (#257941) Homepage Journal
    Things that weigh less are less likely to be torn apart in the wind. They have less inertia, and so will simply move with it instead of breaking. Being slammed into the ocean isn't a problem if they don't fly really low. The main problem would be prevailing winds opposite the direction they're going, forcing more fuel use or something like that. Since the winds are usually west-to-east, this shouldn't be a problem.
  • by ethereal ( 13958 ) on Sunday April 29, 2001 @10:18AM (#257942) Journal
    ...monitor electrical bills watching for people growing pot hydroponically...

    "Honest, officer, I was just adding another 4000 nodes to my Google cluster! Why won't you believe me??"

    Caution: contents may be quarrelsome and meticulous!

  • by KFury ( 19522 ) on Sunday April 29, 2001 @07:43AM (#257946) Homepage
    1) They don't lose contact with it
    2) They converted all their metric units correctly
    3) It does not burn up in the atmosphere on approach


    4) It doesn't accidentally ram and bring down any foreign fighters flanking it.

    Kevin Fox
    --
  • This sorta reminds me of Neal Stephenson's 'Diamond Age', where humanity had perfected nano-tech. One of the more interesting applications was the ability to construct microscopic, vaccuum-filled 'things' to fly around & do all sorts of interesting stuff (law enforcement being one of the primary uses).

    Yeah yeah, balsa wood isn't nano-tech, I know. But the first horse-drawn carriage didn't look much like a Ferrari F1 racecar, either.

    --Mid

  • by Wabi ( 21352 ) on Sunday April 29, 2001 @11:56AM (#257948)
    Folks, look at:

    http://www.aerosonde.com/atlantic_crossing.htm

    This group, using modified RC airplane parts, made such a crossing in 1998. Their plane is now in the Smithsonian.
  • This is what you get when you let brilliant minds do whatever they feel like doing. Somehow, it feels more valuable than what a lot of my working friends are doing at dot-com flameouts.

    There's a lot to be said for letting brilliant people do whatever they want, without giving them much money. It's this sort of spirit that used to drive dot-coms, back before incubators, before the stock boom took off and everything was about stock valuations. Suddenly, millions of dollars were flying around, and everybody was under pressure to turn it into profits.
  • by SEWilco ( 27983 ) on Sunday April 29, 2001 @08:36AM (#257950) Journal
    Return of the successful plane will be by placing the high bid on eBay.
  • by harmonica ( 29841 ) on Sunday April 29, 2001 @03:27PM (#257951)
    ..., some special Texan circuit closes in their brain, and the next thing you know is they are shooting away.

    Thank God none of them is in a real position of power... D'oh!
  • Easy - because as the article said, they're making sure this thing qualifies as a "model airplane" - this limits them to 11 pounds total weight.

    Think about that for a second - that's 11 pounds (5 Kg to those in less enlightened parts of the world) for airframe, powerplant, GPS navigation, computer control systems, radio gear, servos, batteries, and oh yeah, enough fuel to fly across the Atlantic ocean.

    This is a "righteous" hack - my hat's off to these guys. I only wish I were part of their team...
  • Only slow ones. You'll find that any GPS receiver you can buy will cease working once it realizes its moving over 600 MPH.

    As for your second question, I think the US could only benefit from improved culture and entertainment if someone flew a 1000 lb. bomb into the 2002 Oscars... :-)
  • Here is the link to support this project:

    http://www.dc-rc.org/STAR.HTM [dc-rc.org]

    They're looking for donations to help defray the cost of equipment, supplies, travel for the team, etc.
  • by dublin ( 31215 ) on Monday April 30, 2001 @05:53AM (#257955) Homepage
    As someone who started out in computers by building robots to build composite airplanes, I can tell you that balsa has some remarkable properties. Its only real problem is that as you scale up to larger structures, natural defects in the material become more problematic, which is why it's so darn difficult to get large pieces of mil-spec structural balsa.

    There are cases where balsa is notably superior to other materials though - I can give you two right off the bat from modern airplanes: The cargo load floors in some military cargo planes are a sandwich of aluminum skins bonded to a balsa core. Balsa is an ideal core material here, even though it's heavier than alternatives like aluminum or nomex honeycomb, it's also many times tougher and more resistant to the damage that you can imagine the floor of a cargo plane takes, and also makes the floor puncture-resistant. Another example is the wing tank structure in the A-7 fighter jet, another aluminum/balsa composite structure that provides properties unobtainable by using other materials.

    If there were more aerospace grade balsa available (and there are people working on genetic improvements to eliminate grain defects and even grow "square" trees), we would see it used much more often. Many natural materials are far, far better than our best synthetic substitutes, but they're not always in a readily usable form. (Take spider silk fibers as an example - we know they're they're much stronger than anything we can make, but we can't figure out how to make them...)
  • by dman6666 ( 38641 ) on Sunday April 29, 2001 @12:13PM (#257958)
    Not sure if the link you reference meets the following:

    'Hill said his plane will meet the international definition of a model: It must weigh only 11 pounds and be hand-launched. "That's the real challenge," he said.'

    They talked about others too:

    "Technically, his model won't be the first robot plane to cross an ocean.

    Earlier this week, an Air Force robot spy plane successfully flew 8,600 miles across the Pacific from California to Australia. And three years ago, a private unmanned weather reconnaissance plane reportedly crossed the Atlantic from Newfoundland to Scotland.

    But the Air Force drone is bigger than a jetliner, and the weather plane weighed 29 pounds and was launched from the roof of a car.

  • Not a problem, if the destination is in the middle of the desert somewhere. For that matter, the destination coords could be kept in a volatile memory, which loses power if the aircraft crashes, or if it simply times out.

    As for losing the payload, the profit margin is certainly high enough that even a 20-30% loss rate is affordable.

    -jcr
  • by jcr ( 53032 ) <<jcr> <at> <mac.com>> on Sunday April 29, 2001 @05:35PM (#257962) Journal
    Well, I guess this is the solution to the problem of Peruvian fighters shooting down unarmed civilians at the CIA's behest.

    I'm sure it's worth $500 in materials for a drug runner to send a kilogram of cocaine across a border in a package too small for airborne radar to target it. Shoot, with a bit of clever software, they could even do it with a sailplane. (No engine, even smaller radar cross-section.)

    A few years back, the company I worked for was across the hall from a US Customs office in Reston Virgina, and I had a conversation with a customs officer about smuggling technology. I was very surprised to learn that radio-control boats were first used for smuggling liquor across the great lakes and the Niagra river in the 1920's.

    -jcr
  • by eric17 ( 53263 ) on Sunday April 29, 2001 @08:13AM (#257963)
    Now this is great to see. We need more projects like this to keep bored retirees off the street and away from the temptations that are offered there. Why just the other day in the neighorhood Denny's, I was accosted by a grim little man whose bravado was no doubt enhanced by the support of his fellow grandslammers. He yelled in his reedy voice, "Hey buddy! I got my social security! And you're paying for it!!!" which was followed by the raucous laughter of his comrades...
  • I mentioned that to a guy who's building a working replica of the "Spirit of St. Louis"
    He looked at me funny and told me that the plane was steel and fabric. He even rattled off the type of steel it was, mentioned that it's not used anymore for aircraft.

    I'm surprised no one here has thought of ice buildup on the wings of this model aircraft. Maybe they put in some kind of heat pipe on the leading edge.
  • by moeller ( 57451 ) on Sunday April 29, 2001 @09:10AM (#257966) Homepage Journal

    Last weekend, most of the team gathered at the horse pasture in northern Montgomery County lent by veteran aviator Beecher Butts, 88, whose charity has prompted the modelers to name their plane "The Spirit of Butts Farm."

    Hope the wind's aroma isn't too frightening!

  • by norton_I ( 64015 ) <hobbes@utrek.dhs.org> on Sunday April 29, 2001 @09:19AM (#257967)
    A large portion of the cocane in the US comes across the US/Mexico border. Just because it usually involves americans to take part, it still needs to cross the border.

    And no, the US doesn't *just* watch for drugs comming across the border.We do areal survalence looking for people growing drugs, monitor electrical bills watching for people growing pot hydroponically, search inbound ocean vessels, watch for people buying chemicals to make Meth, and any number of of other tactics.

    I happen to think that a large part of the "war on drug"s is irrational, but to suggest that we are naive enough to believe that drugs only come from mexico is just wrong.
  • I just love how everyone assumes that all drugs are coming from outside the USA (atleast I believe thats the 'war' you mean) and somehow doesn't require any americans to take part in the trafficing. Ignorance is bliss I suppose.
  • by mesocyclone ( 80188 ) on Sunday April 29, 2001 @07:56AM (#257972) Homepage Journal
    This technology, inherently stealthy, will no doubt be of great use to folks wanting to move high-value substances across our borders.

    Today, there are dirigible-carried radars along our southern borders watching for smuggling planes. Will they see a plane like this, flying at a few hundred feet AGL? Not likely!

  • by RGRistroph ( 86936 ) <rgristroph@gmail.com> on Sunday April 29, 2001 @09:31AM (#257974) Homepage
    I used to live near Spring, Texas, which in those days had a Goodyear blimp hangar right next to I-45 and near the high school. ( That facility has since been closed, and the Goodyear blimps operate out of Akron, Ohio, as far as I know. )

    I knew lots of "rednecks" ( a lot of them were not real rednecks, just crazy Texans ) that had taken potshots at the blimp at various times. It always seemed stupid to me because those bullets have to come down somewhere, but it didn't occur to me that they were actually hitting their target until my Civil Air Patrol unit took a tour of the blimp facility. The folks there showed us numerous bullet holes and patches on the covering, including one on the edge of the gondola where it attaches to the bag. Some of them described the experience of flying slowly along and just watching while a tiny figure down below blazed away with a deer rifle.

    They had a little collection of hunting arrows, squashed bullets, crossbow bolts, etc that had been removed from the skin.

    About a year after that a bunch of the CAP folks and friends (I wasn't present) were launching model rockets near there and someone got the blimp with that big five foot long Estes "Black Cat" model -- it didn't pierce the skin, it hit a glancing blow and bounced off, and everyone dove into their cars and fled, abandoning some nice rockets.

    Anyway, since we're talking about model airplanes -- the blimp folks told a long story about a powerful model airplane ripping a long gash in the bag, while they were landing somewhere in California. It nearly caused the thing to collapse, it couldn't take off at all until they got a cherry picker and patched it with a massive amount of duct tape, put all they helium they had on hand in the bag and tossed all extra weight, and managed to limp it over to a place where they could work on it better.
  • by RGRistroph ( 86936 ) <rgristroph@gmail.com> on Sunday April 29, 2001 @11:19AM (#257975) Homepage
    A "real redneck" is usually pretty ignorant and uneducated. They are not racist as often as the stereotypes on TV and film would have you believe -- often they are surprisingly willing to take anyone they meet at face value. Rednecks occur in every US state, inspite of the stereotype of there being more of them in the South -- some of the most extreme rednecks I've ever met lived in Massachusetts and New Hampshire. Rednecks are more likely to decide to shoot at a blimp than other people, but most of them are pretty peaceful and friendly, and like most people, not really instinctively aggressive enough for it to even occur to them to start shooting at some random blimp in the sky.

    On the other hand, the "Crazy Texan" personality can be educated and quite sophisticated, but they are still Crazy Texans. There is a substantial overlap between the groups, of course. But an example of a crazy Texan would be Ross Perot, a quite educated person, who still thought nothing out of the ordinary in hiring a bunch of mercenaries to go get his people out of Iran. He understood that there were experts in the State Department and the CIA working on all those things, and that by being a loose cannon he could possibly screw up important national matters -- but the conclusion that all those people were screwing everything up and that by hiring some insane vietnam veterans he could do a better job, is a natural one for the Crazy Texan mentality. But Ross Perot is not a redneck.

    For examples of Crazy Texans, think of the outfits that specialize in putting out oil well fires. Snuffing those with explosives, or plugging them while they are burning, is pretty sophisticated; rednecks can't do it, but it is a job well suited to Crazy Texans.

    So what I was trying to say when I said that the people who were shooting at the Goodyear blimp were often Crazy Texans instead of rednecks, is that these people were smart, college bound, computer literate, New York Times reading people; but if they are sitting at the computer and hear that odd engine sound of the blimp, and go out and look at it, some special Texan circuit closes in their brain, and the next thing you know is they are shooting away.

    Rednecks go fishing. Crazy Texans tie a meat hook with a dead rabbit on it to the trailer hitch of their truck with rope, in an attempt to catch a six foot catfish that was observed in a lake near Houston (true story). When a number of animals from an emu farm wandered into a neighboring subdivision, various rednecks attempted to rope them or shoo them into a fenced enclosure; Crazy Texans were observed chasing them on dirt bikes with roman candles pvc pipe bottle rocket bazookas.

    HTH.
  • Wow, you sure are clueless. I've been flying R/C airplanes for years, and I regularilly buzz the tarmac, even with my low speed human reflexes. If I used a closed loop feedback system coupled with a Sonar and a dampener to avoid wild oscillation, unattended flying at 10 feet above the ground is very achievable.

    You are the weakest link, goodbye!
  • by Chairboy ( 88841 ) on Sunday April 29, 2001 @08:41AM (#257978) Homepage
    The obvious project this inspires is equipping a model airplane with a digital camera, gps, nav computer, and sending it to Area 51 to get some recon shots. Using sonar, you could have the plane fly right on the deck, maybe less then 10 feet high for the final approach and during the evasion afterwards. If your model plane makes a lot of turns and stays at low altitude, there's no way Area 51 security could follow it reliably, and they probably couldn't scramble a helicopter fast enough. Plus, if it's not transmitting, they can't track that either.

    You could launch this baby from Vegas or out in the desert a couple hundred miles away from anything interesting so there would be no way for them to track you...
  • Fast Food companies could one-up drive througs

    Just think of the potential for ordering in pizza and Beer!

  • Well technically this sort of thing has been done once already. As the article mentions, a group of robotics researchers already sent a 29 pound aircraft to make the same flight in 1998. Here is a link [washington.edu]. I believe they are now planning a Pacific crossing. Their original Atlantic plane cost around $10,000 dollars though, its now hanging in a flight museum in the Pacific Northwest somewhere. The plane, named "Laima" after a Latvian Goddess of Good Luck, was the third of four of their planes to attempt the crossing. The first and fourth were lost in transit and the second died because of a flight computer malfunction shortly after takeoff. Now this smaller craft has all the same problems of size Laima did, but with the added problem of significantly flimsier construction and probably weaker flight AI. Somehow I doubt its going to make it but good luck all the same.

  • Just add a camera (how big would it have to be?) and you can start spying on china or whoever. I mean, its immune to radar right (its just gonna like like a bird if it shows up at all).
  • by crashnbur ( 127738 ) on Sunday April 29, 2001 @08:58AM (#257989)
    Wow, what an interesting new device for drug trafficking. Strap the dope in the pilot's seat, fly that sucker at just above tree-top level, send it to Cousin Vinny... Hell, I don't know anything about it, but if this model plane can make it across the Atlantic, then it can certainly carry drugs across a border.
  • Even better idea: Fly a model airplane across the Atlantic powered by a hamster on a wheel.

  • by kfg ( 145172 ) on Sunday April 29, 2001 @10:10AM (#257992)
    That's simple enough. Just make sure that the combined weight of you and your car are no more than 11 lbs.

    KFG
  • by kfg ( 145172 ) on Sunday April 29, 2001 @02:32PM (#257993)
    I'm afraid I don't, and I can't find one either.

    You see, in the old days, 20 or 30 years ago, we used a medium of information dissemination called "print".

    That's about how long ago this happened and if the story has found its way to the web it's hiding from all of us.

    It was two gentleman from the midwest that did this. It took them many years to get a successful crossing. Every year they would travel to Cape Cod, ( by their analysis that is where the prevailing winds eastward gave the greatest chance of success), and release dozens of kites tied to buckets.

    To each kite they attached a note, and HALF of a ten dollar bill, promising anyone that found the kite that they could claim the other half by calling them and telling them where the kite was recovered.

    I might have first run across the story in New Yorker, or it might have been Smithsonian or even National Geographic. I'm really not sure this many decades down the road.

    KFG
  • by kfg ( 145172 ) on Sunday April 29, 2001 @04:01PM (#257994)
    I see someone's been feeding the moderators wacky weed again.

    Flamebait? I can't figure it. It's a true story, one that I have found fascinating for decades and thought others might be interested in hearing about as well.

    Perhaps its absence from the www has convinced someone that it can't be real?

    Life happened before 1990. Not all of it has been transfered to the web.

    KFG
  • by kfg ( 145172 ) on Sunday April 29, 2001 @10:16AM (#257995)
    In point of fact wood is stronger than steel * per pound.*

    It is strength per unit of weight that is critical in this particular undertaking.

    And contrary to what most think softwood is stronger than hardwood * per pound.*

    ALSO contrary to what most people think Balsa is a hardwood, not a softwood. The terms hard and soft wood are biological classifications, not an actual discription of the wood.

    KFG
  • by kfg ( 145172 ) on Sunday April 29, 2001 @10:18AM (#257996)
    The Isreali army already uses R/C model airplanes for various missions. They are unsurpassed in effectiveness for short distance recon.

    KFG
  • by kfg ( 145172 ) on Sunday April 29, 2001 @10:22AM (#257997)
    A kite has already made the trip across the Atlantic unattended.

    The kite was tied to a bucket which was filled with water and dropped into the sea. The bucket held the string of the kite and the kite dragged the bucket with the prevailing winds.

    Cape Cod to Ireland.

    KFG
  • by kfg ( 145172 ) on Sunday April 29, 2001 @02:24PM (#257998)
    I'm sorry, I meant to make a quick and interesting post, not write a monograph on the various mechanical properties of wood.

    I rather thought that what I meant could be at least roughly deduced by the reader by refering to the subject at hand.

    I meant in overall properties, given the certain structural shapes and assembleges germain to stick built objects such as houses, cars, and . . . model airplanes.

    As you intimate structural materials have many different properties. Wood, unlike steel, is not isotropic and so its properties are greatly effected by its orientation to load, at least in its natural state. Bear in mind that there are many high tech composite wood products these days with rather remarkable properties. But since the subject is balsa I'll confine myself to wood as she comes from the tree.

    Wood has a tensile strenth of about 5 ton f/in.^2, mild steel is about 28.

    Mild steel has an elongation percent at failure of about 20. Wood is close enough to zero to count. In a situation where dimensional stability is of higher importance than unltimate failure strength wood is often the superior choice.

    Mild steel's Young's Modulus is about 30 lbf/in.^2 * 10^6, wood only about 1.5. Wood is less stiff than steel, however its elastic limit is very, very high. Wood will bend and return to its original shape in ways that make it in many cases a more desirable structurual material than steel.

    But things get REALLY interesting when we start to look at beam strength. Beam strength goes up by
    * the square of the cross section.*

    Given the need for a particular beam length, ohhh, say the main spar of an airplane wing just to pick a hypothetical example at random, and the need to keep weight down, a wood beam of * the same weight* will be of markedly greater cross section, and again, * strength goes up by the square of the cross section,* The wooden spar will be stronger than the steel spar. Or we could, as an alternative, make the wooden spar of somewhat smaller cross section, giving up strength but * saving weight*.

    It would be perfectly possible to build model airplanes out of steel. It isn't done not because of cost,(steel is cheaper than balsa), not because of constructiion difficulties, ( balsa plane construction is no piece of cake and working with steel isn't significantly harder), it is done because it results in a structurally superior product * per pound* than using steel would. ( And please note that when the cross section gets sufficeintly large it is perfectly possible to gain all the benfits of tubing with wood. Sailboat spars are constructed this way as well as wing spars for airplanes)

    Using stressed skin construction makes up for wood's low Young's modulus yielding remarkably stiff structures.

    That, in a nutshell without writing a formal monograph, which I refuse to do, is what I meant by 'strength.'

    When we get into the more modern composite materials wood looses some overall 'strength' but gains isotropicness.

    In the field of military aircraft two planes in particular, from two different world wars, stand out as having such a reputation for sturdiness and ablility to take fire that they are legends to this day. From WWI there is the Roland C-2 "Walfisch", and from WWII there is the Mosquito. Both of these planes were molded wooden composite. The Roland was so sturdy that by the end of the war the tailgunners were in the habit of shooting at enemy plane * directly through their own fusilage!*

    Now THAT is strong, but you won't find that kind of 'strong' in any engineering reference or ANSI standard.

    By the way, what are YOU smoking. You havn't a clue what the terms softwood and hardwood mean. The gentleman in the post below you got it right. Go look it up.

    Oh, and you COULD have correctly criticized me for one thing, I should have said "botanical" classification, rather than " biological", but you missed my ACTUAL error. Go figure.

    KFG
  • by snyrt ( 151824 ) <snyrt@onebox.com> on Sunday April 29, 2001 @11:25AM (#257999) Homepage
    i read the article yesterday in the post. One of the most amazing parts of this whole project is that the main man is legally blind and mostly deaf. he put the plane together in his basement using lots of really thick pairs of glasses and he dyed the glue pink so that he could see it. i think that's pretty cool.
  • by mikeboone ( 163222 ) on Sunday April 29, 2001 @08:28AM (#258004) Homepage Journal
    Let's see a cost comparison with the USAF's Global Hawk (which flew to Australia a week ago).

    :)
  • by TeknoHog ( 164938 ) on Sunday April 29, 2001 @08:12AM (#258005) Homepage Journal
    "We could sit around and vegetate," Hill said. "But why do that when there's something interesting and fun and challenging to do?"

    Now go and ask yourself that question.

    --

  • by danheskett ( 178529 ) <.moc.liamg. .ta. .tteksehnad.> on Sunday April 29, 2001 @09:51AM (#258006)
    Scramble a helicopter? How about use a net?

    I can see it now - the cartoons of the future generations will show inept civil/military employees chasing RC spy planes rather than the rascally neighborhood dog being chased by the inept dog catcher.

    ~sigh~ Back in my day...


  • by NousCS ( 180385 ) on Sunday April 29, 2001 @04:52PM (#258008) Homepage Journal
    http://www.acm.org/ubiquity/views/j_raskin_1.html [acm.org]

    August, 1998. On South Uist island in the Outer Hebrides, off the west coast of Scotland, a group of men huddled around a van, jacketed against the 25 knot wind. There was no way that they could hear the sound of the aircraft's engine over the persistent whistling of the gale; they would see it -- if they saw it at all -- before they would hear it. And it was an hour overdue on a potentially historic flight.

    The small, single-engined craft was attempting the first solo flight across the Atlantic, but this was more of a solo than the one Lindbergh made some 70 years earlier. Where there had been one pilot on that flight, which was for Lindbergh the irreducible minimum crew, there was none on Laima. The plane was trying to fly itself solo from one side of the ocean to a particular spot on the other side. Instead of a compass and stars to steer by, it had a microprocessor and a global positioning system (GPS) receiver...

    Read the rest at:
    http://www.acm.org/ubiquity/views/j_raskin_1.html [acm.org]

  • by commandate ( 183229 ) on Sunday April 29, 2001 @04:21PM (#258009)
    In the February 01 Wired, look at Seascan, a joint
    Insitu Group (http://www.insitugroup.com) and University of Washington Aero/Astro (http://www.aa.washington.edu)UAV. Fall flight target: cross-pacific on a "few"
    gallons of gas. Interesting communications, instrumentation.
  • ...it was under a contract from the U.S. Office of Naval Research, made by a corporation for a University. It was launched from a moving car. And it was over twice as heavy. The current plane is an entirely grassroots kinda thing.
  • by KurdtX ( 207196 ) on Sunday April 29, 2001 @07:45AM (#258014)
    Sorry, but honestly, I can't wait to see a commercial app out of these. Newspaper companies could use fleets of them to deliver papers (particularly to remote houses). Fast Food companies could one-up drive throughs. It could even solve some of the US Postal Service's troubles [slashdot.org]

    Of course that begs the question: aren't we lazy enough already?

    Kurdt
  • Suddenly, millions of dollars were flying around, and everybody was under pressure to turn it into profits.

    Actually, the dot-com flameout was due to there NOT being any pressure to make a profit!
  • by Spinality ( 214521 ) on Sunday April 29, 2001 @09:16AM (#258021) Homepage
    Plus batteries. -- krokodil

    Remember they have a little 1Hp internal combustion engine. It could generate electricity pretty cheaply and efficiently. Or a little cellphone lithium-ion battery should give plenty of juice. I doubt they're maintaining continuous contact in either direction. Some of the earlier posts suggest the plane is being operated by remote control, like those lame battling robots on TV. But I'm sure the computers are there to make this thing semi-autonomous, checking GPS fixes and sending return telemetry at relatively infrequent intervals (i.e. not constantly) to keep radio use down. The thing is steering from waypoint to waypoint, like commercial autopilots, maintaining a predefined flight profile without somebody steering the thing.

    This project is so cool, I'm sure these guys are having the time of their lives.
  • Glass Fiber is as heavy as you make it. For ultra light models a foam core with *thin* glass fiber covering is used (no balsa, maybe some Carbon Fiber). These planes can be far lighter than similar balsa models. While these can be weak you can add as many layers of fiber as you need. One of the problems with balsa is its tendence to shatter on impact and its inability to tolerate higher speeds. Surfaces tend to flutter and bend during high speed maneouvers. Even counting the fact that 45+30(probably max windspeed they'll aim for.) isn't very fast. Over more than 40 hours of continious stress is going to test it.

    There's also the added weight of engine components (extra ply doublers etc.). You could probably built a lighter model of glass fiber, and I'd give it better odds of a sucessful flight.

    It would also depend on the auto-pilot how much stress would be on the air frame. IIRC auto-pilots on models use the horizon for leveling. If it's very sensitive they may end up with a problem like MIT (?) had when they built cars that followed the one in front.

    --
    Murphy Bitter
  • by Murphy Bitter ( 216703 ) on Sunday April 29, 2001 @08:00AM (#258024) Homepage
    The real question is whether the weather will work in their favour. Assuming that they have a model that will fly the distance. If it's too sunny the wings may warp (twist) causing an increase in drag and more problems for the autopilot. IIRC rain doesn't mix well with mylar, although I'd guess it's been sealed because of engine output (fluid etc.). They didn't say what king of engine they are using, if it's a glow engine they may get more problem with rain.

    I'm not quite sure why they didn't build a glass fiber model. It isn't that difficult to do. They usually run well in the rain, if slower.

    It should be interesting to see how well they do.

    --
    Murphy Bitter
  • by Murphy Bitter ( 216703 ) on Sunday April 29, 2001 @08:06AM (#258025) Homepage
    "Opening at an airport near you Hamster Airlines. A low cost solution to moving you pets."

    --
    Murphy Bitter

    P.S. I have heard of people putting hamsters in models, they usually don't survive. The G's are usually way too high.
  • by khendron ( 225184 ) on Sunday April 29, 2001 @08:34AM (#258027) Homepage
    Wind is not the issue. The difficulty is turbulence. However, if all the wind around a body is moving in the same direction and at the same velocity, then from the body's point of view there is no turbulence. If the body is light and not fixed to anything (like, say, a model airplane) then the body is unlikely to notice the effects of the wind.

    We humans tend to notice wind as very turbulent because

    • We are usually fixed to the ground and do not move with the wind.
    • We are usually deep inside the boundry layer of the earth, where ground effects and obstacles (trees, building, etc) cause all sort of turbulent eddies.
  • Birds fly over the open ocean. Birds weigh less than 11 pounds. Ever see a bird just sitting there in a gust of wind when it should be moving forward? Assuming good engineering, and given the altitude of the plane, it should be fine. Don't assume that it's weak just because it's balsa wood either. Five pounds of balsa wood (well, probably considerably less when you factor in surface materials and electronics) is plenty to build a craft to stand up to ocean winds.
  • I work in a secret government lab

    Not any more...
  • Aren't you the one posting that on Slashdot? Wait, aren't I replying to it? So much wasted energy! Must find something interesting and fun and challenging.
  • Yeah, and put on a cell phone to upload live shots of the fly by. Better yet, use an iridium phone as long as the sattelites are still floating. Of course, Iridium phones weigh about 5 pounds (a big reason for their failure), so that might be a mistake. I doubt the cellular reception is very good in Area 51 though.
  • by Erioll ( 229536 ) on Sunday April 29, 2001 @12:21PM (#258034)

    Ask ANYBODY who has flown a model airplane about your "10 feet off the ground" maneuver. Any little gust of wind will have it crashing. Whenever I do any maneuvers THAT close to the ground, it is the hardest, and most stressful part of flying. I can see small, light computers being able to fly a plane across the ocean using waypoints at a few thousand feet. Lots of time for compensation for gusts, etc. But terrain-following? Get real.

    This isn't to say someone SHOULDN'T try flying a plane over Area 51. I think that'd be cool. Since you aren't going trans-ocean (maybie only from the next state, or somewhere similarly annonymous) a good high-resolution camera wouldn't be that difficult to mount. Flying at 300-400 feet AGL, you would still get awesome pictures. And with a transimitter, even if your plane gets shot down (by rifles, etc. Wouldn't be that difficult to hit, even at night. The heat of the engine would be easy to spot) you will still have the images. :)

  • by Kletus Cassidy ( 230405 ) on Sunday April 29, 2001 @08:35AM (#258035)
    Suddenly, millions of dollars were flying around, and everybody was under pressure to turn it into profits.

    What dotcomm was that? The one universal thing all dot-coms I've heard of did was avoid any attempts to make any sort profit whatsoever. Selling stuff at cost(buy.com), delivering stuff to your hone without charging for delivery (kozmo.com), not charging for shipment of computer equipment(outpost.com), delivery costs more than the actual item (pets.com), spending hundreds of millions before launching a website (boo.com), etc.
  • by spoocr ( 237489 ) on Sunday April 29, 2001 @07:39AM (#258039)
    Well, at 2000 feet, you'll get some pretty strong winds, and balsa's not exactly that strong. Wouldn't suprise me if a good gust just snapped a wing off.

    Also, 45 mph (Target speed) == 66 ft/sec. If the wind was to, say, force the nose down (As you say, it'll move - or change orientation), it would take just over 30 seconds for the plane to descend to ocean level, and that's not taking into consideration the extra velocity added by the wind. Granted, the engineers could probably pull it out before then, but what if they encountered a strong, continual downdraft?

    -- Chris

  • by spoocr ( 237489 ) on Sunday April 29, 2001 @07:25AM (#258040)
    At 11 pounds, won't it be incredibly susceptible to winds, especially over the open ocean? Towards the end of the journey when its gas is almost gone, it's going to weigh probably something near 5 pounds - it seems like it would be too easy for it to get caught in a gust of wind and slammed into the ocean, or torn apart.

    -- Chris

  • by spoocr ( 237489 ) on Sunday April 29, 2001 @07:34AM (#258041)
    "Dropping bombs down airshafts, not just for the USAF anymore!"

    Don't you mean the Rebel Alliance?

    "Great shot kid, that was one in a million!"

    -- Chris

  • Yeah they mention this but it is not considered a model plane because of its weight. Needs to be 11 pounds at maximum to be a model plane.


  • by MadCow42 ( 243108 ) on Sunday April 29, 2001 @08:33AM (#258043) Homepage
    >> If the wind was to, say, force the nose down

    GPS systems not only give you your location in latitude/longitude, but also provide elevation. I'm sure they're not stupid enough to let this thing fly without checking it's own elevation to make sure it stays at 2000'.

    With that data, and some cool programming, they wouldn't even need to know the orientation of the plane (even if it were upside down). (However, I have a feeling that they also have instruments to measure orientation).

    At 66'/sec, the GPS data would change at a fast enough rate that they could make fairly quick analysis of what direction they're going, and what effect control surface changes have. If they decide to pull the elevator "up" and the plane starts going the wrong direction, they can assume that they're upside-down and make opposite corrections. Heck, they could have programmed it with no knowledge of how to "turn left", but rely on the GPS data to tell the plane if it's doing the correct thing (random control movements, feedback analysis of results).

    I'm sure it's simpler than that though. q:]

    MadCow.

  • by dhowells ( 251561 ) <slashdot@domhowells.com> on Sunday April 29, 2001 @07:33AM (#258047) Homepage Journal
    Now all we need is for someone to write the three-line-perl-RSA-implementation on the side of it for the most stylish arms-trafiking stunt in history.

    Seriously tho' doesnt it occur to anyone that if this does succeed, it could have very serious implications for smuggling (Like thinks how much crack this thing could carry with it per-flight with a little modification),

    Of course the simple internet minded solution would be to legally threaten the balsa-growers, the plane-sellers, and the gasoline-vendors while letting the crack whores continue unmolested.

    ------------ Dom Howells
  • Well, at least it'll float!

    Daniel

  • My guess is that in that case, as well as in the drug transport scenario mentioned above, designing a controller to give this thing much accuracy is probably difficult. Even with a GPS, it's still pretty much at the mercy of the wind. Not to belittle their efforts, but "Europe" is a pretty big target compared to Area 51 or Vinny's backyard. I'd consider an RC job much more viable. With this thing, you could likely get some photos (not necessarily the ones you wanted), but to retreive them it would have to send a homing signal.
  • by DysonSphere ( 307033 ) on Sunday April 29, 2001 @07:40AM (#258056)
    As a kid I used to build "stick and tissue" CO2 powered models with a simple pendulum "guidance" system. Trickiest part was getting the right amount of friction at the pendulum pivots to keep the model from over-compensating, and to design around the center of gravity shift for the pitch control. Once the rig was setup properly though, you could "program" it to do all sorts of neat stuff, by offsetting the pendulums. Balsa kits were around $5.00, and pendulums were made from fishing weights and paper clips.
  • by capt.Hij ( 318203 ) on Sunday April 29, 2001 @09:23AM (#258063) Homepage Journal
    It is not uncommon to find Monarch butterflies in the UK that narrrowly missed their normal migration route to Mexico. Once in the air the prevailing winds can pull the craft across. If a butterfly can survive the shear forces then a model plane should have no troubles.
  • Cool thing to do: Go to a hobby shop near you and check out a finished plane. Usually the staff there have a few (or more) models which they've built and use for display. You can see firsthand that it's not just the wood, but the covering and wing mounting hardware that all combine to make one seriously strong and light platform.

    Now, keep in mind that I said "properly built" in the first post. If it's not glued properly, it'll suck :)

    Robyn
  • by squeegee_boy ( 319210 ) on Sunday April 29, 2001 @07:55AM (#258065)
    Actually, you might be surprised just how strong (and light) a properly designed and built balsa wood airframe can be. Covered with mylar (MonoKote or similar) these things are durable, stiff, yet flexible enough to take many poundings. I have built and flown several model airplanes (powered and non-powered) in my life. Frankly, my piloting ability stinks, and I've witnessed first-hand how well these things can survive the earth rising up to smite them. A storm would just vlow it around a lot, and probably eat up the fuel supply long before it broke anything. -Robyn
  • by number one duck ( 319827 ) on Sunday April 29, 2001 @07:47AM (#258066) Journal
    Smuggling isn't a problem. I work in a secret government lab, we are already training genetically modified seagulls to bring these babies down (at least during mating season).

  • by number one duck ( 319827 ) on Sunday April 29, 2001 @08:07AM (#258067) Journal
    On the other hand, you wouldn't be able to fly these things over my neck of the woods... the rednecks shoot at *everything* that there isn't a law against...

  • What is the difference between a "real redneck" and a "crazy Texan"?
  • by kcelery ( 410487 ) on Sunday April 29, 2001 @08:01AM (#258069)
    Cruise missle? No, its unlikely. But watch out for the guided model planes flying from Columbia to California.
  • by glenebob ( 414078 ) on Sunday April 29, 2001 @11:42AM (#258073)
    Balsa is a hardwood, not a softwood. The terms hard and soft wood are biological classifications...

    To clarify the point:

    Hard woods come from deciduous trees. Simply put, if a tree has leaves, it produces hard wood (oak, alder, maple, balsa, etc.), if it has needles it produces.. um.. not hard wood (cedar, pine, fir, etc.) Which doesn't make alot of sense, but there you go :-)
    --
    Damn it Jim, that's my sphincter, not a jelly donut!!!

  • by sllort ( 442574 ) on Sunday April 29, 2001 @08:09AM (#258074) Homepage Journal
    No disrespect intended, but I'm not sure you know what you're dealing with [angelfire.com]. As an R/C modeler, I can tell you that the incredibe tensile strength of stretched, bonded mylar that we coat our planes in combines very well with the compressive and torsional strength of balsa to create some really sturdy aircraft. I've flown balsa gliders into precision landings in winds gusting up to 50mph.

    Lindbergh's plane was cloth over wood!

    As far as mounting telemetry in these suckers... yawn? [spyplanes.com] Yes, they make a perfect delivery system for a terrorist. Zero cross section on radar, silent, incredibly hard to see, and they can carry a decent payload.

    The big holdup has always been the telemetry, which is quite different than a robotic aircraft. Robotic R/C planes, if perfected and made cheap, would be... a law enforcement nightmare.

    My guess is that they (law encforcement) have already thought about this for a while.
  • And it's the gas that's probably the most expensive part of the aircraft.
  • by House of Usher ( 447177 ) on Sunday April 29, 2001 @08:37AM (#258076) Homepage
    Cost Comparison: USAF's Global Hawk
    Fueling - $150,000 a tank
    Computer Technicians to keep it in the air - $20,000 a day
    Actual aircraft - $15 million dollars

    Spirit of Butts Farms
    Fueling - $2 dollars premium unleaded
    Computer Technicians to keep it up in the air - they're doing it for the thrill
    Actual aircraft - $30 dollars depending on what grade balsa wood is purchased

    The view from Ireland when the plane arrives - Priceless

    For everything else, there are copyrighted slogans from our favorite credit card companies... ;-)
  • by Francis Frisina ( 447570 ) on Sunday April 29, 2001 @07:21AM (#258077) Homepage
    that the practical applications of this are phenomenal! :) Just kidding. It is actually pretty neat. Three thousand (give or take) miles per gallon - now if only my CAR would be that efficient!
    ---
  • by Francis Frisina ( 447570 ) on Sunday April 29, 2001 @07:24AM (#258078) Homepage
    1) They don't lose contact with it
    2) They converted all their metric units correctly
    3) It does not burn up in the atmosphere on approach

    Sorry, couldn't resist! :)
    ---

  • by dtmos ( 447842 ) on Sunday April 29, 2001 @02:43PM (#258082)
    Robotic aircraft is a popular avocation, viz.: Aerial Robotics Competition [gatech.edu], The Association for Unmanned Vehicle Systems International [auvsi.org] and, in particular, their Unmanned Air Vehicles page. [auvsi.org] Each of these sites has links to many other projects.
  • by dtmos ( 447842 ) on Sunday April 29, 2001 @01:42PM (#258083)
    Ah, but that's the advantage of a small model, with a length on the order of six feet. Getting torque from the wind requires a wind vector differential over a distance equal to the size of the model, and unless one is in a tornado one is unlikely to be in winds that differ significantly (from a structural survivability standpoint) over a distance of six feet. Maintaining proper attitude and directional control, of course, is a separate issue, but not an insurmountable one.

    It's no exageration to say that Maynard Hill is the world's greatest living R/C aircraft modeller, so I'd have to say that betting on him is the smart play. He's been doing this type of thing better than anyone else for a long, long time ... since the 1950's.

"No, no, I don't mind being called the smartest man in the world. I just wish it wasn't this one." -- Adrian Veidt/Ozymandias, WATCHMEN

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