converting foam glider to RC rocket boosted glider

I have been thinking about takign one of those big foam gliders you see everywhere and converting it to an RC glider, then adding a pod to make it a Rocket boosted RC glider.

now this means that I'll have to add reciever, servos, and battery to such unit. I assume that I can take the existing glider, find its CG, and position the gear so that the CG stays the same.

after that, I'll have to find a way to have the servos do something. I saw the frankenfoamy, and did not like the looks of it. I was wondering if I could change the lift characteristics of the control surfaces by creating drop flaps?

Also, i want to keep the gear nice and light, but not at an extreme cost. battery life will be measured in seconds, not minutes. I have a 4 ch RC radio in the air band (from my hangar queen trainer) so I would like to use that to keep costs down.

Reply to
tater schuld
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People have been messing with those planes for a while. Ever heard of the wally wing? I made a glider version once.

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Essentially. Rocket placement and selection are the hard parts. There's plenty of formulas on line for determining max altitude and velocity based on the motor and the cross sectional area of the plane and it's weight. The rocket will also get lighter as it burns it's propellent, so you will have to take that into account if it is mounted away from the CG.

Man are you bored. I'd be more concerned about the thing shredding on launch.

One of the main disadvantages of rockets is that it costs at least a few bucks per launch. But it is just an experiment anyway. Give yourself at least a couple minutes of rc control (not seconds) and be prepared to get it back on the ground before time runs out. Have fun.

Reply to
Steve Banks

Unless it's a Kyosho F16 or the like with thick wings and low aspect ratio, and NOT one of those 3-4 foot span things, you are totally wasting your time - you'll shred it to bits. I don;t know what else is out there like the F16 so not sure what you have in mind.

You say you are trying to keep costs down - the only motors that will get a big foamie to a useful altitude are those with a long gentle burn the likes of the E6, F12RC etc. Why cheap out on the glider and force yourself to use relatively expensive motors? Better off to build a decent glider that will boost on D12's or E9's. I suppose you could drop stage D12-0 to E9 or D12, but..

BTW battery life measured in seconds is not possible - for a battery to have small enough capacity to truly be good for only a minute or so's worth of flying, it will likely have too high an internal resistance to power servos. The minimum you could consider may be 50mAh NiCADs. By the time you invest in those or even 100mAh, and a charger that won;t cook them, and do what you have to to make the foam glider hold together, I think it will be a lot of screwing around to get a poor flying piece of foam in the air.

Edmond's Arcie II is a good example of how "cheaply" and simply you can make an R/C boost glider. All sheet balsa. If scratch building, for simplicity's sake nothing beats a delta. Why not do a 1.5X or so scale up of an Estes Skydart or something like that? BT60 body, sheet balsa wings, elevon control. Just the ticket.

Others have made good flying models out of Coroplast and fly them on D12's and E9's. That's a cheap way to have some workable fun.

Just wonderin' what you are trying to accomplish.... if your goal is a low cost functional R/C boost glider than I'd shy away form the foamies as I think you might be disappointed with the end results, possibly with the exception noted at first.

BTW I'd guess you own standard size servos from your trainer, and they are pretty porky for a project like this, likely ~18-20 grams a piece at least.

Mike D.

Reply to
Mike Dennett

Not if you use a soldering iron to route out a channel for some thin bamboo spars, and tape up like a Zagi with the nylon packing tape

With those lifelike $4 gliders, take most of the sweep out of the wing and reduce the dihedral, glue together with the thin bamboo or carbonfiber rods, use the polyurethane foaming glue with tape to keep the glue from expanding everywhere

Use Sullivan red goldenrods routed and glued to the tailboom, but replace with balsa the Rudder and elevator, though I have left some foam as the vert. stabilizer, but you need to build up the rudder to match the profile

Foam with spars and tape will hold up to D12 power, even parallel staged D12s.

forget landinggear, just tape the bottom of the fuse.

For noseweight, hollow the nose, insert a kids balloon or condom, fill with water, knot off. tape so it won't fall out

when boost is done, use the rudder, when moved to full limit, to release a springloaded pin. Balloon pops, water drains away, getting your CoG back to where the glider will fly well.

oe use a plastic bottle with a vent, placed so water wont drain when in a climb state, but will in level flight

Try to keep everything under 16 oz, heavier than that, and single D12 power won't lift you far.

For the weight penalty of a 9V battery, you can use electric switches to ignite a 2nd D12 in air, or use it to fire an igniter to pop the waterballoon, if you had extra channels on your radio- or use throttle up to fire the D12, throttle down to pop the balloon, if you had a small reversing speed control and some diodes Watch servo weight, but you can use AAA sized cell for battery

** mike **
Reply to
mike

Refer to

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much information on building your own rockets as well as how to make your own rocket fuels etc:

scroll down to: "FAQ = Answers for Beginners and Advanced RC'ers" in particular see the web page =

U-2 Convert styrofoam gliders to RC

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then scroll down to: "Rockets" Animated model rocket engine burn. Experimental Rocketry Site Jetex Engineering -- Microjet -- Rocket Science Institute John Kallend's rocket page Model Rocket Illustrated - 3D cutaway views of the parts of rocket. Model Rocket Strobe Light National Association of Rocketry New Zealand Rocketry Northern Illinois Rocket Assoc. Public Enemy Rockets Quest Model Rockets & Engines rec.models.rockets FAQ Table of Contents R/C Rocket Boosted Gliders Rocket launcher Rocketry Online's INFOcentral Scale Model Rockets Scale Rocket Kits Shuttle Countdown Online Shuttle Model Homepage Model Rocket Club Links

regards Alan T. Alan's Hobby, Model & RC Web Links

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Reply to
A.T.

Of course if he's talking about a Zagi or the like small slope glider, well now that's a different story. Zagi had a version designed for E15's did they not?

Reply to
Mike Dennett

glider, well

They do have a lot of different models, wouldn't be too suprised if they had one at one time.

I did have a Klingberg rocket wing, but that was more a handfull than the others, given how minor CG shifts effect things with a wing. Hands off on boost, with that one.

I'd stay away from flying wings, but go with a regular fuse of some type, that classic 2M shape.

The converted foamy was lighter than the old estes builtup kits like the stratoblaster, and actually flew better in glide with the higher aspect wing, not that those foam wings have a great airfoil, either

Cut into the wing and add some goldenrods to move barn door ailerons. the buried rods help stiffen the wing as much as added in spars- if not, cut in about 2/3rds out on the wing and put in some polyhedral, or chop the wing there and play with different tip plates.

These are cheap, and with the radio gear taped up inside holes in the fuselage, damage resistant enough for somebody with low time on the sticks to not wreck the gear in crashes.

Since time and $$$ invested is so low, you can fly these more, and experiment

** mike **
Reply to
mike

I'll buy it. I've seen a few attempts at foam conversions and they seemend like a bit of a waste to me, but heck for a bit of cheap fun I guess why not? It was just my opinion that better performance could be had for about the same cost and effort going other routes. I mentioned the Kyosho F16 because a while back I bought one after seeing I think it was Nick Ziroli's R/C .049 conversion. I planned to make a free flight boost glider out of it. Haven't done it yet though. I think those models are hard to find, or may be OOP. Dunno.

Reply to
Mike Dennett

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