STORY PROBLEM: Earthbound Airplane-- What to power it with?

Marmot · Post by **Marmot** » Mon May 22, 2006 10:00 pm

We are mutating a small homemade airplane frame into something that will roam the playa. The question is what to motorize it with. Right now, we have a small ATV-- a 70cc Yamoto available to us. It is rated for a payload of 180 lbs, but we figure we will need to load up about 600 lbs. including riders and frame FYI, it is air cooled.

My hope is that the ATV manufacturers are expecting you to use the rig as an ATV, and that under normal operating circumstances, 1 person will be trying to haul ass on dirt roads and up hills and such.Obviously, we will not be hauling ass, and the playa is so completely flat. I mean, if people power parade floats w/ lawn mower engines, hopefully this little ATV can do the duty for this applicaiton.

If it is not yet obvious, we have more ambition than sense when it comes to mechanical engineering. This will be a learning experience, no doubt.

Can any of you geniuses pleassssse weigh in? Can we pull this off with the ATV without melting the engine? Or should we get something else? A tractor perhaps?

Thanks, thanks, thank you, I hug you, thanks for the advice in advance,

DJ MARMOTOVSKI

ibdave · Post by **ibdave** » Mon May 22, 2006 10:11 pm

Not to rain on your project, But I'm sure you can't fly something of that size within the area of space occupied by people. So that will leave you only outside the trash fence. The airport won't let you use that area also..I think its a cool project. Were going to fly a RV para glider around our camp with a camera on it. Then give CD with the video to camps near by..

Try these fine folks.. http://www.burningman.com/on_the_playa/ ... index.html

My wife just pointed out that you might be talking about an artcar.. Right?? If so My Bad....http://www.burningman.com/on_the_playa/ ... index.html

Dork · Post by **Dork** » Mon May 22, 2006 10:24 pm

I'm sure there's a way to block up the suspension like many car-based mutants do. I wonder about the gearing, though. How easy is it to maintain 5MPH under load? Is the engine running at a happy rpm at that speed?

ibdave · Post by **ibdave** » Mon May 22, 2006 10:28 pm

Now that DORK has posted, I see you meant an Art Car... Sorry about my 1st post...

Tiahaar · Post by **Tiahaar** » Mon May 22, 2006 11:40 pm

Marmot wrote:We are mutating a small homemade airplane frame into something that will roam the playa. The question is what to motorize it with. Right now, we have a small ATV-- a 70cc Yamoto available to us. It is rated for a payload of 180 lbs, but we figure we will need to load up about 600 lbs. including riders and frame FYI, it is air cooled.

Can any of you geniuses pleassssse weigh in? Can we pull this off with the ATV without melting the engine? Or should we get something else? A tractor perhaps?

Thanks, thanks, thank you, I hug you, thanks for the advice in advance,

DJ MARMOTOVSKI

Darn you for summoning the eplaya geniuses of mechanical alchemy...I am duty-bound to respond even if it is 11:25pm on a worknight

Here's my farmboy 2 cents worth of things to look at:

Can the frame and tires/wheels handle the load? as Dork said the suspension can be blocked so it doesn't sag, also spread the load out to fat outrigger casters if you can (wing wheels, nosegear?)

Is the engine strong enough? an online guide says a 70cc atv engine makes @ 11 hp in its powerband, so if you run in low gear to keep the rpms in that band at 5 mph you should have plenty of power.

Will the engine melt? Yes, so add a cooling fan so it thinks its going along at 30 mph, and be nice to it on hot days. Running engines under load at low speeds with insufficient air flow for cooling (parades do this) will overheat them, happens all the time.

Good luck, sounds fun! I'll watch for a little airplany playa roamer out there.

Marmot · Post by **Marmot** » Tue May 23, 2006 9:14 am

Oh man, I love you people. Thank you Mr. Gay Farmboy Mechanically Gifted guy!

Now, any specific tips on what to use for bolstering the suspension and what kind of fan to use? Do we just buy the beefiest f-ing shock absorbers we can find?

Please look for a falcon-like ornithopter on the playa and come fly with us.

Msr. Marmot

Lassen Forge · Post by **Lassen Forge** » Tue May 23, 2006 10:13 am

Marmot wrote:Oh man, I love you people. Thank you Mr. Gay Farmboy Mechanically Gifted guy!

Now, any specific tips on what to use for bolstering the suspension and what kind of fan to use? Do we just buy the beefiest f-ing shock absorbers we can find?

Please look for a falcon-like ornithopter on the playa and come fly with us.

Msr. Marmot

Been kicking this around. Threw it at Sgt Bibinova, our lead air crew cheif and porta potty scrubber at the Apokiliptika R&D Hangar # 62-c, who came up with these thoughts...

Couple things to think about. If the plane is on tricycle gear (2 under the wings (or thereabouts), one under the nose) you can beef up the shocks, or build angle-iron struts to encase the gear to make it inflexible. Of course, either one will f*** up the landing gear, but if it's a bad airframe to begin with...

If it's a taildragger, you may want to build the rear strut from scratch to get the plane level. Again, you can weld it from angle and have it work. Again, will f*** up the airframe.

Which is point 3. Airplane frames are not the most solid and rigid things. Make sure it's beefy enough to hold the expected weight, especially "taxi-ing" on the ground! Also, if you plan on making the wings rideable, they'll have to be beefed a bit, too.

As to engineering problem 2. The fan.

For stationary testing of motorcycles, I've used those 24-30" plug in sit on the floor specials from Home Despot, but you need a long extension cord!! >grins< You *could* pulley the drive motor and the fan and use that to drive it, but it'd suck HP from the motor (more than you would think!!). You might be geared low enough to get the motor spun fast enough to make that a non-issue, I don't know. IF I was doing it and had the space, I'd run the a second motor (like a small briggs or something) and pulley it to run a fan to cool both. You could also incorporate a pulleyed alternator on this motor for electricity/battery for lights) to again save driven power for power.

sorry, have to go - the mig is back - damn loose wings.

bb

Ugly Dougly · Post by **Ugly Dougly** » Tue May 23, 2006 10:18 am

You got wings on that thing? It might prove interesting to handle once the wind picks up.

I'm of a mind that strapping a bunch of model rockets to its aft end would work wonders.

Marmot · Post by **Marmot** » Tue May 23, 2006 12:33 pm

"You got wings on that thing? It might prove interesting to handle once the wind picks up. "

We may have the *impression* of wings, but are they wings? We hope not. We have had our souls scoured and scortched by the Black Rock winds 5 times now. This airplane's liftoff will not take place into the air, but daily flights of fancy are scheduled to tour the peaks and valleys of our hopes and fears.

Marmot · Post by **Marmot** » Tue May 23, 2006 12:39 pm

I'd run the a second motor (like a small briggs or something) and pulley it to run a fan to cool both. You could also incorporate a pulleyed alternator on this motor for electricity/battery for lights) to again save driven power for power.

NOW WE ARE TALKING FOLKS! I love this idea.

Not to worry about landing gear, etc.-- there is no belly on the beast-- it never gestated far enough along to get one. It will mount on a quad and we will add further stablization from there if needed. You would not believe how light it is, but I think it will be pourous enough to not get broadsided by wind, etc.

Will take all the ideas you all are willing to spare.

DJ Marmot

hunter S · Post by **hunter S** » Tue May 23, 2006 4:49 pm

Marmot, fan problem- go to a motorcycle salvage & pick up fan & radiator off an eighty's vintage street bike. should run you about $30-$40 bucks a 12v battery will handle the power & the bike fan & radiator should hang easly from the atv frame.
Use one ruber hose from one hose niple to the other (just keep water in the radiator might drop a few ice cubes in from time to time) Your not prerizing the system so even if it leaked a little water probable wouldn't matter.

Marmot · Post by **Marmot** » Wed May 24, 2006 8:59 am

Might a tractor be a better choice than the ATV? They seem to be designed to pull/push large loads. If the tractor goes inside the plane's cabin, and then some sort of frame and wheels are built to suspend the plane, the tractor could push/pull the frame and thus negate any suspension issues.

I guess the cooling issues might still be there.

Just processing out loud...

DF Marmot

Tiahaar · Post by **Tiahaar** » Wed May 24, 2006 10:13 am

Marmot wrote:Oh man, I love you people. Thank you Mr. Gay Farmboy Mechanically Gifted guy!

Now, any specific tips on what to use for bolstering the suspension and what kind of fan to use? Do we just buy the beefiest f-ing shock absorbers we can find?

Please look for a falcon-like ornithopter on the playa and come fly with us.

Msr. Marmot

Ha, I like it! If I ever get a sock I can be Mr. GFMGG (and why doesn't anyone ever accuse me of being a sock??? I feel so neglected)

Not sayin the atv is out yet...but is it geared (like you have a hand clutch and shifter) or is it (and I'm thinking it might be at only 70cc) a centrifical auto-type thing? 'Cause the latter sometimes don't like lugging around at slow speeds.

If geared and you can do the fan thing somehow like others have said the atv may work but if you've got a lawn tractor or even better an actual small farm tractor with water cooling and radiator fans and all go for that. Tractors rock.

robotland · Post by **robotland** » Wed May 24, 2006 2:05 pm

One thought about cooling- Give thought to the position of the drive system while (Or before) building, and allow easy airflow or construct so that air is easily ducted to and around the "hot bits" and thenceforth away from said "hot bits" carrying with it the heat from those "hot bits".

"Hot Bits".

"Hot Bits".

YAYYY! I finally got "Meat Hat!" out of my head!

"HOT BITS!!!!!"

Meat Hat

theCryptofishist · Post by **theCryptofishist** » Wed May 24, 2006 2:07 pm

Tiahaar wrote:
Marmot wrote:Oh man, I love you people. Thank you Mr. Gay Farmboy Mechanically Gifted guy!

Now, any specific tips on what to use for bolstering the suspension and what kind of fan to use? Do we just buy the beefiest f-ing shock absorbers we can find?

Please look for a falcon-like ornithopter on the playa and come fly with us.

Msr. Marmot
Ha, I like it! If I ever get a sock I can be Mr. GFMGG (and why doesn't anyone ever accuse me of being a sock??? I feel so neglected)

You sock! Stroking your own ego by prasing your suggested solution to your imaginary problem and then capping it off by praising the name you gave yourself.

You disgust me!

Is that better?

Marmot · Post by **Marmot** » Wed May 24, 2006 4:03 pm

YAYYY! I finally got "Meat Hat!" out of my head!

Thanks. I think you just infected me with the "Meat Hat" meme.

--Marmot

Tiahaar · Post by **Tiahaar** » Wed May 24, 2006 10:04 pm

theCryptofishist wrote:
Is that better?

Most excellent

and oh yes "Hot Bits!!"

Marmot · Post by **Marmot** » Thu May 25, 2006 8:56 am

My wife just pointed out that you might be talking about an artcar.. Right?? If so My Bad....http://www.burningman.com/on_the_playa/ ... index.html

Well, we prefer to think of it as a mutant airplane, but if you are going to split hairs, I GUESS it could be considered a car, since with any luck it will never fly. The Wind Godz may have different planzzzzz...

--Marmot

dragonfly Jafe · Post by **dragonfly Jafe** » Thu May 25, 2006 10:22 am

...mutant vehicle is the PC term...

As far as making it go, you have two basic choices; Powered and Unpowered. All powered vehicles must be pre-registered (not all are approved) by june 30 or so (see BM website for details, search on DMV). Unpowered (ie-human powered bicycle or pulled by rope) vehicles do not require registration (at least not yet).

Assuming you want a powered vehicle, you can either gut a car or golf-cart or lawn-mower (remove the blade!) down to the chassis and add the plane to that, or add a new engine to the plane. If you go with a new engine, electric is a common choice but the motors, controllers, and batteries are not cheap. Another option is to use a gas or diesel engine (basically making a giant go-cart). Whatever you do, make sure you can easily kill the engine, and be sure you have plenty of braking power. Also be sure you can easily control the speed at a steady rate at and below 5mph.

Good luck!

Marmot · Post by **Marmot** » Thu May 25, 2006 12:52 pm

So it comes down to this: ATV or tractor?

Place your votes now please...

-Marmot

Dork · Post by **Dork** » Thu May 25, 2006 1:00 pm

If you have the option, tractor. Built to happily travel at 5MPH pulling a load. Not necessarily CARRYING a load, so some suspension beefing might still be required, but at least the engine should be happy.

mojo · Post by **mojo** » Thu May 25, 2006 2:09 pm

My burning question is - is this an airframe with foldable wings? If not, how in hell are you getting it to the playa?

Marmot · Post by **Marmot** » Thu May 25, 2006 2:55 pm

My burning question is - is this an airframe with foldable wings? If not, how in hell are you getting it to the playa?

Ah. You assume wings. It didn't come with wings. But in this case, we will make detachable wing-type things for easy transport. Plus, decouple the tail and cabin. Then reconstruct on the playa. It will be about 16-18 feet long when complete.

Mmmmm. Modularity. Rrrrrrr.

--Marmot

STORY PROBLEM: Earthbound Airplane-- What to power it with?

STORY PROBLEM: Earthbound Airplane-- What to power it with?

Re: STORY PROBLEM: Earthbound Airplane-- What to power it wi