RE: Here's A Simple & FREE First Foam Build Plan! (Part 2)

RE: Here's A Simple & FREE First Foam Build Plan! (Part 2)
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RE: Here's A Simple & FREE First Foam Build Plan! (Part 2) - 3/21/2009 3:37 PM

critterhunter

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Next is of 1/8" balsa being glused to the side of the fuse and booms with gorilla glue. I try to not get the glue too close to the edges because it will foam out. If it does, it can be cut of with an exacto knife or sanded away with a belt or orbital sander, which I normaly use anyway to get the edges of the balsa even with the foam. Trying to cut it flush with a knife is too hard to do most of the time. Weights are being used to keep the foam and balsa tightly pressed together as the Gorilla glue will try to push things apart.

Next is of two carbon tubes being glued into the wing. I melt the channels out with a soldering iron and then glue them in with Gorilla glue. I'm using two carbon tubes because it helps the fuse and tail booms solidly fuse to the wing and prevent damage during a crash. I like to tape over them with Tyvek tape (meant for foam and found at home improvement stores) as it sticks better than clear packing tape but clear will work. The tape won't stick to the glue very well so you can peal it off after it's dried. By laying the wing flush on the ground and weighting it this helps to keep the glue from foaming out. You can see that the second carbon tube is short to keep it from running into where the future ailerons will go on the wing. It's length is roughly just long enough to cross where both booms will be, roughly 12" plus the width of both booms.

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RE: Here's A Simple & FREE First Foam Build Plan! (Part 2) - 3/23/2009 2:35 PM

critterhunter

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Forgot to mention that the booms are 20" long. More pictures...

I glue the fuse on first using Gorilla glue by using a ruler to measure from both wing tips to the fuse to center it. After that I glue the booms on by measuring out from the sides of the fuse. The boom span is 12". It's important to weight things down and also use a little tape to hold it in place as the glue will try to push things around. Again, I try to keep the glue away from the edges so there is less that foams out to peal away.

Next is of the horizontal stabilizer and elevator. I used flat carbon in both to stiffen them. Notice that the one on the stabilizer is longer so that it will go into the booms for added rigidity. I hinged them together using small Great Planes hinges, much better than Dubros. To do this I slit the foam with an exacto knife. After a test fit to glue them in I just take a hinge and dip it's end in Gorilla glue, then insert it into the slit. Once all the slits have been dipped with the hinge this way (this hinge isn't used on the plane) I wipe away the excess. It doesn't take much glue to work well. I then assemble the two pieces together and then take some oil and coat the hinge pivots so that if any glue foams out it won't stick well to the hinge pivot.

Next is of the horizontal stabilizer being glue into place flush with the top of the booms. This time I used epoxy because this surface is too thin to use Gorilla glue without a mess of glue foaming out. I put weights on both sides of the booms to squeeze them snug with it and also put some tape over the joining to make sure it stays snug while the epoxy sets. The booms have been notched to accept the flat carbon, keeping the h-stab flush with the top of the booms.

By the way, think I forgot to mention why I sheeted the fuse and booms in 1/8" balsa. I used to put carbon tubes in them but balsa is cheaper, makes things nice and stiff, and also will cause a clean break should you wreck, where as the foam would tend to squash and been with carbon tubes in it.

Next is of the vertical stabs being epoxied in place. I used Cell Foam 88 for the tail feathers but blue foam or meat tray foam from your local butcher works well too. I used tape and toothpicks to hold the v-stabs straight while the epoxy set.

Next is cutting the ailerons out. To do this I taped a metal ruler in place and then used a mini bow to cut them out. The mini bow is simply a fiberglass rod with some fishing leader tied to both ends. The fiberglass is bowed to load the wire with tension. If you keep the electrical connections a half inch or so away from the tied ends the wire there won't get hot and melt through the fiberglass. This bow is roughly 14" or so long and works fine with the newer charger set at 6v 10amps start/boost. The fiberglass rod was from a patio umbrella I garbage picked. This things are loaded with rods and they work great for strengthening wings as well.

Next is of the ailerons hinges and installed. I used flat carbon to strengthen them and cut the holes for the control horns via a dremel and a burring bit. I screwed up in that I should have sanded an angle into the wing and not the aileron so the aileron won't bind. Instead I sanded it into the aileron which requires the control horn to sit back further from the hinge line. This should be avoided since if it isn't right over the hinge line you'll get unequal up/down throws. I'll have to adjust that via my transmitter's travel adjustments.

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RE: Here's A Simple & FREE First Foam Build Plan! (Part 2) - 3/23/2009 2:41 PM

critterhunter

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In the second photo you can see how I mounted the motor. What I did was take three strips of bass wood and glue them on top of each other. I then glued this to the top of the wing, sinking it into the wing by melting out a hole. The motor is held to it via some nylon bolts that the basswood was then drilled and tapped for. I'll put a touch of epoxy on top of the bolts to make sure they don't vibrate loose, yet I can crack this glue to remove them later if needed. The motor was mounted on top of the wing so the prop would clear the ground and also so that center of gravity would be easier to achieve than it would if the motor was hanging off the back of the fuse. This motor is a 2409-12T, which would work great for this plane. However, I re-winded the motor for to produce better thrust, speed, and efficiency. Some other good motor choices for this plane would be the 2409-18 or 2408-21.

Final picture for now is of the plane, ready for electronics.

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RE: Here's A Simple & FREE First Foam Build Plan! (Part 2) - 3/27/2009 5:58 PM

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Last of the build photos. Leading and trailing edges of the wing and h-stab/elevator tapes with Tyvek to help protect them.

Next photo is of the electronics installed via melting out wire channels and chambers for the electronics. You can also see the servos installed. I just melt out chambers for them then wrap the servo in masking tape. A little Gorilla glue in the chamber (not too much or it will migrate over to the horn) to snug it up. I like doing this because the Gorilla glue will form around the servo body and really make it snug. To remove the servo just slit the tape and pry it out.

Next photo is of the bottom of the fuse covered in Extreme strapping tape (Office Max or Staples). This will protect the electronics and also help to hold the fuse together in a crash. I later melted some vent holes through the tape and Ultracoat covering so keep the ESC cool.

Final picture is of the completed bird covered in Ultracoat. All up weight with a 2200ma 3 cell lipo is 29 ounces. Motor is a 2409-12 but is rewinded for better efficiency/performance. 30 amp Tower Pro ESC. Although it probably didn't need it I installed an external BEC. Servos are HXT900s. RX is a 6 channel GWS. Plan to maiden this weekend.

I may make a new battery hatch (it's held on via magnets) out of thinner balsa as this one looks pretty stupid. Also may make a new motor cowl that looks better.

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RE: Here's A Simple & FREE First Foam Build Plan! (Part 2) - 3/27/2009 6:03 PM

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*applause* Good job Crit. Like the ultracoat covering, makes it alot more visible in the air.... Still having that "bug" to make another Soo, time to get more foam. Ever tried the EMAX series motors from hobby city? I love the 28-22 1200 (believe the first specs are right), shure would throw a Soo around.

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RE: Here's A Simple & FREE First Foam Build Plan! (Part 2) - 4/1/2009 9:21 PM

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Here's my latest build nearing completion. 7x48" Clark-Y wing. It and the V-Tail were parts I had made a year or so ago and had laying around from other planes. The coruplast V-Tail was one I made for an Aerobird Extreme when I used to fly one, slightly oversized for more surface area and control. The boom is an aluminum crossbow bolt. The bottom of the fuse is sheeted in 1/8" basswood for added durability (didn't have any balsa laying around to use). The wing has a carbon tube in it and is bent for dihedral. The motor is a 2409-18 custom winded by Alex to a very low 870 k/v or so. It's swinging an 11x5.5 APC prop and should produce a lot of low speed torque to help push the draggy airframe through the air. Tower Pro 30 amp ESC and two HXT900 servos. GWS RX.

I still have to do a few things to complete it. Namely, the wing was my very first covering job back when I made it so I plan to recover it. I didn't understand the concept of pulling the stuff tight to avoid wrinkles back then. I still need to make a battery hatch and hold it on with my standard magnet configuration. I also need to make a cone like cowl to put in front of the motor mount to streamline that as well. V-Tail also needs painted black as some of the old paint has pealed away.

This plane is a tribute to the Challenger and Extreme that I learned to fly RC on. It's also really my first plane with landing gear if you don't count "Big-N", which never really flew. I wasn't planning on making it an AP plane but it turns out the fuse is fat enough to safely hold my pocket camcorder, so if it flies well I'll later install a camera compartment at COG to do AP work with. This plane turned out looking much like my current AP platform, although that one uses rudder/elevator controls and has a higher k/v motor on it.

I'll probably finish this plane up tonight and also will be finishing up a Stryker platform tonight as well. That makes 5 planes ready to fly. Maybe I can stay ahead of the crashes this summer and always have something to put into the air. Next project will probably be finishing up the P38 I showed some pictures of a few months back. That will be my first dual motor plane.

The yellow color looks light and washed out in the pictures. It's Ultracoat in bright yellow but didn't show up well for some reason.

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RE: Here's A Simple & FREE First Foam Build Plan! (Part 2) - 4/2/2009 12:18 AM

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Just finished up a Stryker build using many mods I've learned over the years. AUW is 26 ounces. Not too bad considering all the strength mods. New build log with numerous tips I wrote can be found here...

http://www.rcuniverse.com/forum/m_8631014/tm.htm

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RE: Here's A Simple & FREE First Foam Build Plan! (Part 2) - 4/3/2009 2:36 PM

critterhunter

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Went out with five planes to maiden yesterday. Happy to say that none of the planes were damaged, although two would not fly.

The Vortex (swept back wing EDF platform I threw some pictures up of a few months back) wants to nose up and stall. I think it's very tail heavy and will try adding some weight to the nose to see. If it still doesn't want to fly then a friend is bringing me one of his glassed Projectile bodies (flying wing) to install it on. Having two EDF units on hand I'm anxious to build some kind of platform that will fly. You might remember I built a Klingon bird of prey a while back which also wouldn't fly.

The V-Tail pusher won't stay in the air. The low k/v wind on the motor, swinging an 11x5.5 prop, just doesn't have enough power to keep the plane in the air. I'll try a higher pitched prop on it but if it still won't fly I'm going to rewind the motor to a higher k/v.

The Stryker flew very well and really moves along with the Go Brushless triple stator motor. Unlimited verticle. While it's slower due to the draggy airframe than my streamlined Stryker was on this motor, it is still plenty fast enough for me.

The "So" flew great. Unlimited verticle and pretty fast thanks to a great wind a friend uses on the 2409-12 or 18 motors. I like this wind a lot. The plane rolls and loops very well.

I'm real happy with my glider with the 6' wingspan. It's very fast on the 10x7 prop and 35-36 1100 k/v motor and has unlimited verticle. I mainly built this plane for lazy days riding thermals but it's nice to know that it can also do some high speed stuff.

This plane uses a single aileron, rudder, and elevator. For having only one aileron it rolls pretty darn good for a glider. Loops are good too. This plane has a fiberglass rod in the wing and under high speed looping it flexes pretty far but no distortion to the wing or covering when inspecting it on the ground. I had to lower the elevator rates because with it's speed it's just too easy to flex the wing a lot. Even at lower rates with less flex it still loops nicely. I have to get a 10x7 APC folding prop for this plane because it's not fun making sure the standard prop will clear the ground on a landing.

I'm pretty happy with the maidens of all these planes, despite the two not flying. I'm anxious to get out and fly more but I see it looks like rain for the rest of the week.

Time to work on the P38.

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RE: Here's A Simple & FREE First Foam Build Plan! (Part 2) - 4/10/2009 8:54 PM

critterhunter

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After sitting for about a year I've finally got the FW42 German bomber ready to maiden. If she flies then I'll doll her up with landing gear and make her look pretty. Canard incidence and COG can be tricky to get right on a canard setup.

Current AUW is 31.5 ounces. Not too bad. The two custom winded 2409-18 motors are I think around 1300 k/v and swinging 8x6 contour rotating props. She'll easily do unlimited verticle in my static run tests. Speed shouldn't be too bad, either. Wing loading is about 12 to 13 ounces so she should float pretty well too.

Using dual 40 amp Super Simple Escs. HS81 servos. GWS RX.

Although the Germans built wind tunnel models of this plane it never made it into production. The plans were found years later in the rubble of a complex. She's a rare bird in RC. I've currently only been able to track down 5 RC builds, and out of those only three survived the maiden.

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RE: Here's A Simple & FREE First Foam Build Plan! (Part 2) - 4/10/2009 9:35 PM

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Wow looking nice, you (may) want to try sweeping the wings back or the plane maybe next to impossible to CG. Looks like a nice build there with the dual motors.... Landing gear may help on the maden because of the fact that it won't allow a super nose heavy plane to fly

Dying to see that P-38 in the backround...

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RE: Here's A Simple & FREE First Foam Build Plan! (Part 2) - 4/11/2009 3:46 PM

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Thanks. I've got the center of gravity set at 10% static margin so CG is where it should be. If it flies I'm going to add landing gear with steerable nose wheel, gunner ports, olive green covering, motor cowls, and nazi symbols.

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RE: Here's A Simple & FREE First Foam Build Plan! (Part 2) - 4/13/2009 3:08 PM

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Wonder where Fisher and Saucerguy are? The So has been flying real well and has proven reliable when my other planes are crashing. The FW42 nosed in on it's maiden launch. It will fix easy. Think I have too much down thrust in the motors. The Stryker crashed on me yesterday. I lost it in the sun and when it came out it was in a death spiral, managing to hit the only patch of cement around. Almost no damage thanks to my strength mods and will fix quick (minor chunk of foam came off the nose mount). I've been making a new wing for my glider and will glass this one as the other folded on me in a hard pull up. Fuse is fine.

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RE: Here's A Simple & FREE First Foam Build Plan! (Part 2) - 4/14/2009 3:49 PM

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Lord Hunter you continue to amaze me. Well done.

The one pictured here from your builds looks like it would be pretty easy to convert to a water based design. Couple of sponsons on the ends of the wings, small rudder in the center section could be tied to the ailerons if it doesn't already have a rudder set up.

Maybe something for you to consider.

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RE: Here's A Simple & FREE First Foam Build Plan! (Part 2) - 4/14/2009 6:21 PM

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Thanks. My true love these days is hot wiring EPS foam and building my own designs. Yea, more than a few people have said that it should make a good water plane. A friend has built a few dual boom boat planes after he saw my "So" dual boomer.

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RE: Here's A Simple & FREE First Foam Build Plan! (Part 2) - 4/16/2009 2:51 PM

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Got a tip for anybody shopping for servo wire. Was at Hobby Town and found out that they sell 3 wire train wire, 7 feet for $3, and it's exactly like any other servo wire but much cheaper

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RE: Here's A Simple & FREE First Foam Build Plan! (Part 2) - 4/20/2009 4:20 PM

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Figured out why the 30 amp ESC burned up in the Stryker. After replacing it with a 40 amp I lost control the other day. No damage and couldn't find any problems as to why it lost power. Thought it was a glitch. The other day I took it up again and this time I heard something that didn't sound right and lost power again. Again, no damage, but this time I found that one of the motor bearings was binding badly. Seems that probably caused the 30 amp esc to burn up by over amping it, and was the reason why I lost power the last two times as it would freeze the motor when it got hot enough. At least the plane has no damage.

I'm done with the FW42. After it's first nose in maiden I raised the ailerons with the flap switch to force it to keep the nose up on launch. This time it launched but had way too much climb. Killed the flap switch and it dropped it's nose and crashed. Major damage since I hadn't sheeted the fuse yet. Done with canards. The gear is going into the P38.

Bird of prey made it's maiden yesterday. Since the suggested COG was about 1.68" ahead of the wing I went for 2" to be safe. It was WAY too nose heavy and dug the nose into the ground. I adjusted the elevons for more lift. Max possible, but still it nosed in. No damage. It did track well I just couldn't keep the nose up. I'm guessing that I have to move the COG back at least an inch because extreme climb trim would not compensate. Any opinion on if 1" is going to be too much or not enough? I'm guessing it might not even be enough but would rather lean nose heavy. I'm fairly confident this plane will fly well because it felt good despite not being able to lift the nose.

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RE: Here's A Simple & FREE First Foam Build Plan! (Par... - 4/23/2009 4:10 AM

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quote:

Nice to see you guys are game for the new thread. I'm hoping Fisher and Saucerguy will pop in and contribute, as well as the others from the past who did.

Wow, step out the door for a couple years and look what happens! You guys are still hard at it, building SOs (and some really nice looking ones, by the way) and having fun!

Well a lot of water has flowed under the dam at home for me, and no time for flying. I had my planes in a utility closet, and they gradually got crunched as the closets filled up with building materials. My J3 and the old taped up SO trainer I flew so much.

A couple weeks ago I pulled them out, all the pieces. Dusted them off, got out the old glue gun, ripped off old tape, rebuilt whatever was needed, and headed out one morning at 6:30 AM to try to fly again.

The J-3 was first with a new hotwired Clark Y wing, instead of the old sheet foam undercamber. But it still showed some of it's old bad habits no use in any wind (and there were some surprise gusts even at 6:30) and unstable in yaw. I think the fixed vstab is way too small compaerd to the barn door rudder and balance tab. It was all over the place. So I brought it in after a few uh, impacts.

Next was the SO. I revved it up and chucked it, and even old and pieced together and overweight as it was, it climbed out perfectly in trim and perfectly stable, just as it always had. Like an old trooper. I brought it around to return over the tree line and........wump! What-the? I was sure I had that treeline made.

NOT AGAIN!

Yes, again. This is like Charlie Brown and the football. My love of trees. Total pilot error this time. I guess I better wear glasses now when I fly.

I think that tree grew in 2 years.

Anyway the SO was hung up at the very top. and underneath were fifty more trees. No way it was coming out of there any time soon, if ever. Way too high to climb. Too high for a pole. And I wasn't going to go through that slingshot routine again.

This time I went and got my Stihl with the 24 inch bar and cut the thing down.

Hoping I could cut the wedge and hinge just right to turn it on the way dow and cushion the SO.

Uhhh, well I guess I also better wear glasses now when felling. It kind of didn't turn, and kind of made a lot of white foam bits.

So I spent the rest of the morning limbing and cutting up that old black birch, and at least next winter we'll have a little more firewood already dried.

Anyway, I'm thinking about a new SO, and thought I'd drop in for a laugh or too with you guys!

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RE: Here's A Simple & FREE First Foam Build Plan! (Par... - 4/23/2009 5:04 PM

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Good story and nice to see you back! Be sure to post pictures of the new build. I had the same pilot error with my So the other day. I was getting major glitching from the normal landing zone so I figured I'd bring it in from behind me. Coming in for a perfect landing and I ended up wacking the frequency sign's pole! Luckily it hit dead center on the nose and only damaged that a bit, and I was planning on chopping off some extra nose anyway because the plane is a tiny bit too nose heavy. no other damage and the perfect place to hit. I can remove that and she'll be better than new with the shorter nose.

I'm finding that 2.1" for the COG on this 7" wing is a bit nose heavy and causes it to want to fly with a bit up climb in the elevator, as well as landing a bit fast. I'm guessing about 1 and 3/4" or a bit more should provided a better COG point.

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RE: Here's A Simple & FREE First Foam Build Plan! (Par... - 4/25/2009 3:09 AM

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Critterhunter, glad the damage was not a problem!

I will certainly show info on any new build.

It's funny though, I don't know how many times I've read this in these threads, but somebody reports that they've totalled a SO, and the next day they go back and look at the pieces, and go.....hmmmmm.
maybe I can put a little glue her and a little tape here, and fly this again. And like as not they actually do.

I got that feeling myself tonight looking at the pieces of my SO. Not that I'm going to rebuild it, because too much is missing. It would be easier to start fresh than make up and patch in missing parts. And probably faster to build a new one.

But I'm thinking of salvaging the wing, which is still in one piece a few dents and cracks, and the top engine mount split off. But I can put the mount back with one line of hot glue. And I can repair the cracks and dents in 10 minutes, and have myself a nice polyhedral wing again, with motor, and at the correct downthrust line, which I worked out by trial and error before. There's a chunk of fuselage left I could just cut cleanly and add to. The booms are gone.

So instead of making a twin boom SO with it, maybe I'll go for a single solid foam fuselage. It might look a little like a flying boat with the pylon on top some motorized sailplanes had this as well, and I might go for that look. I can keep the pusher configuration, and protect the prop that way. (Man I went through a lot of props on the J3 Cub!). I don't know, something I'm thinking about. A salvage challenge.

I agree with you on the need for up elevator trim on SOs. Every configuration I tried different motors and placement in two different planes needed it. I think this is because the wing incidence isn't quite high enough, so the tail has to force the plane down to bring the wing incidence up enough to lift.

In your case you use a dead-flat bottom airfoil, instead of a slightly raised nose like a true Clark Y has. This raised nose makes the airfoil act like it's angled up a little. Yours isn't.

You also tend to build heavy er, I mean strong

and so the wing needs to be angled up even more in flight to support the weight. The only way this can happen is for the tail to point the plane up slightly.

I'm going to guess therefore that moving the CG back won't eliminate your need for a little up trim. Since you still have to angle the wing enough to support the same amount of weight no matter where it is in the plane. I could be rotally wrong, it's just a guess.

If I guessed right, the way I think you could get rid of the need for trim would be to shim the wing leading edge up (on the booms) next build. Maybe a couple degrees. Nothing drastic.

I don't think the main body would need shims since the relationship between the wings and the stab are what matters. And the booms connect those together.

I'll be curious to find out if the nose surgery and CG difference changes your need for up trim. Like I say I could be totally off base.

One other question Critterhunter, did you ever fly that TA-152 (I think that was the name of the plane) that I tiled those drawings for? I was curious to see how that flew!

< Message edited by vtrc -- 4/25/2009 3:17 AM >

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RE: Here's A Simple & FREE First Foam Build Plan! (Par... - 4/27/2009 2:45 PM

critterhunter

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No, never flew the TA-183. I cut up the body for an EDF and it wasn't looking right so I scrapped it.

Made a mistake. I meant the COG probably needs to balance at about 2 1/4th inches and not 1 3/4. I was thinking backwards there. I've built other So's that didn't need the climb trim in the elevator and never shimmed the wing, but I noticed on the prior build to this one that it was also nose heavy at 2". I do put a lip into the airfoil on the bottom leading (by sanding it) to help with the airflow. Took the bird out yesterday and it still needing up trim but then again what I took off on the nose didn't amount to much weight. Think I'll try adding some weight to the rear temporarily with tape and see if the trim problem goes away. It's not a big deal, but I would like to slow the plane down a bit for landings, and if the COG fixes that then fine. This build isn't as heavy as my prior ones and some of those landed slower.

You could be right about shimming the wing but remember that a Clark-Y already has 3 degrees of positive built into it. My motor thrust angle is right on so that isn't it either.

< Message edited by critterhunter -- 4/27/2009 2:46 PM >

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RE: Here's A Simple & FREE First Foam Build Plan! (Par... - 5/1/2009 4:17 AM

vtrc

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Hey look at the "Big Brother" plans here (on the free plans page):

http://www.willingtons.com/mymac/Plans_Download.htm.

It's a 92" WS motorglider in balsa drawn back in 1996. Looks like a stretched out SO!

Re. the Clark Y:

Critter, I thought I remembered from way back when, that you used a modified Clark Y with the curve removed from the bottom, so it was straight right to the leading edge?

Maybe I'm misremembering.

Anyway an airfoil like that wouldn't have the 3 degrees positive A.O.A. from the bottom flat.

The reason the true Clark Y has a positive AOA compared to the flat bottom is that it's furthest point forward is above the bottom foil line.

So when you draw a line through the absolute leading edge to the absolute trailing edge, it is angled up about 3 degrees from the flat.

< Message edited by vtrc -- 5/1/2009 4:23 AM >

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RE: Here's A Simple & FREE First Foam Build Plan! (Par... - 5/1/2009 2:43 PM

critterhunter

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My wings are flat on the bottom, but I sand a lip on the bottom leading edge a bit to help with airflow. It's either going to be a COG problem or wing incidence like you said, but like I said I've built So's in the past that had no need for up trim. I'll weight the back a bit and report back on it.

I couldn't open that file for the pusher glider. Don't have the right software. Anyway you could post a picture of it as I'd like to see that thing.

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RE: Here's A Simple & FREE First Foam Build Plan! (Par... - 5/4/2009 2:05 AM

vtrc

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quote:

ORIGINAL: critterhunter

I couldn't open that file for the pusher glider. Don't have the right software. Anyway you could post a picture of it as I'd like to see that thing.

Okay critter, here are some converted .gif screenshots of the file as originally opened up in Turbocad LE.

They're Autocad .dwg drawings originally.

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RE: Here's A Simple & FREE First Foam Build Plan! (Par... - 5/4/2009 2:22 AM

vtrc

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And now, how about this:

quote:

Record Breaking Paper Airplane

This 1992 photograph shows a world record breaking paper airplane inside a hangar at NASA's Langley Research Center in Virginia.

Image Credit: NASA

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RE: Here's A Simple & FREE First Foam Build Plan! (Par... - 5/4/2009 2:36 AM

vtrc

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Took awhile to find an explanation for that photo, but I believe this is it. That may actually be the 30 foot span one.

quote:

For the past year students from four high schools in Hampton, Virginia, have spent much of their free time working towards a common goal - setting the Guinness record for the world's largest paper airplane. Doctor Ferdinand Grosveld, a Lockheed supervisor working at NASA's Langley Research Center, came up with the idea as a way to get students excited about engineering and science. As chairman of the local chapter of the American Institute for Aeronautics and Astronautics, Doctor Grosveld approached four accomplished engineers, retired from NASA, to serve as advisors in the project. One was Collier Trophy winner Dick Whitcomb. They taught the students aeronautical concepts like lift and drag, then let them come up with their own original designs. They were fast learners, according to Jim Penniman. Weeks later a guy was able to tell me what aspect ratio and how to calculate it when it was only mentioned a time or two so I felt like that he learned well. Fellow advisor, Bill Reed, was equally pleased. The real purpose is a lasting one, and that's to stimulate these young minds, and I see it happening. The record they were trying to break was a sixteen-foot wingspan flying a minimum of fifty feet. Paper and adhesives were the only materials allowed in construction. The greatest challenge was keeping the planes from collapsing under their own weight, an obstacle overcome with an innovative tube rolling technique devised with the help of Hewitt Phillips. Fly-offs in the Hampton City School's gym were used to evaluate student concepts. Although this eighteen-foot version seemed capable of breaking the record, the students decided to work towards an even larger model in case someone established a new mark before their attempt. As part of the project, the students visited NASA Langley Facilities, including this subsonic wind tunnel where they participated in an aerodynamic study involving a scale model of a transportation aircraft. Thanks to Virginia Soaring, they were also able to experience firsthand the forces on a giant paperlike plane, taking rides in a glider piloted by NASA contract engineer, Mahmed Tekalu. Finally, the day the students had been gearing up for came. In a hangar at NASA Langley they hoisted their twenty-four foot model onto a platform as specified in contest regulations. With record officials and numerous supporters on hand, senior Kevin Kelly let the plane fly. It had to go fifty feet to break the record. It traveled over twice that far, and the students weren't done yet. With Will Perry doing the honors, they broke their own record using this twenty-eight foot version. Then as a grand finale, they launched a thirty-foot craft, achieving yet another new milestone - one hundred fourteen feet, nine inches. Kevin Kelly summed up the emotions of the day. It's been a long project, and to come down and be able to break the record and the plane fly as well as it did, I'm really happy. It's been a great experience. The record-setting craft will now be displayed in Virginia's new Air and Space Center alongside other historic planes signifying the dedicated teamwork and learning experience of all who participated. It's maybe like the Olympic Games. You know, participating is more important than being first.

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