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Old 09-10-2009, 06:38 AM
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BarelyAWake BarelyAWake is offline
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Default Re: ultralight/moped anyone?

Originally Posted by TerraPilot View Post
Justthisguy, you are bout to become just this other statistic. Its been done to death. I know more about what it takes to fly than any other person on this thread. If you knew what I know you would place your lips to the ground and plant one big juicy kiss there. Know that if you continue along your present course you have but one more kiss and that will be when the mother earth kisses your ass goodbye. Drop the subject until you've learned considerably more.
I hope I'm not too blunt. I also know the Wright brothers better than anyone else here too. Someone forgot to mention the Wrights had a catapult for take offs. Thats another design issue in itself, you know?
Not to rattle a cage - but man, yeah... this was a bit too blunt o_O

If it wasn't for enthusiasm and a willingness to go out on a limb like justthisguy's, none of us woulda strapped these 2smokers to our bikes - let alone anyone inventing the airplane. I think we were doing a fine job of pointing out safe, viable alternatives... whereas your post seemed focused on just shooting him down.

Some of the things I dearly love about this forum are the creative spirit, the general friendliness, and most of all - encouragement.

I admit this is a bit trivial - but how the **** do you know "more about what it takes to fly than any other person on this thread" - particularly given this was your second post ever on this forum? You haven't the slightest idea whom you're referring to, for all you know - I could be a direct descendant of good ol' Orville himself...

Ultralight flying is primarily home builds, most if not all the pilots experiment with their planes and quite a few build from scratch, myself included. While we warned him that it would be better to start with a proven engine/airframe design, even linked a few possibilities - we didn't try to just get him to "Drop the subject".

There's actually quite a LOT of crossover between motorized bicycles and ultralights, both are home builds & usually kits - necessitating quite a bit of "creativity", both are usually 2 strokes and all of the idiosyncrasies that go along with them, both are very sensitive to design alterations yet have endless possibilities.

I for one was quite enjoying this thread, please keep your buzzkill to yourself kthx

Last edited by BarelyAWake; 09-10-2009 at 06:50 AM.
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Old 09-10-2009, 11:07 AM
freewheeling frank freewheeling frank is offline
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Default Re: ultralight/moped anyone?

man i just have to say something here, i am not a licensed pilot but i have been on the stick i had an uncle who was a korean war pilot he drove p38s and i think an early jet it was a long time ago. also flew with aguy who was a ww2 pilot also flew p38s he built his first plane from plans from popular mechanics in the 30s in his dads barn i t6hink he ran a mockormick tractor mill in it he died in a plane i know he was smiling, so remember orville and wilber, they had balls, maybe im rambling, nuff said
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Old 09-10-2009, 11:17 AM
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HoughMade HoughMade is offline
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Default Re: ultralight/moped anyone?

Back to the nuts and bolts....and there is nothing wrong with dreaming.

A moped that will do 30 mph with just it and a rider will not make near that speed given the size of wing needed to get whatever weight you have off the ground.

You are right about the human powered crafts- they are amazing feets of engineering- particularly the materials they use...and those materials are difficult to obtain and expensive.

Dream on...but realize that there is a reason you don't find 3 or 4 hp flying machines. Trust me, if that worked, you would find them on the 'net.
29/10ths cubic inches of raw power.
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Old 09-10-2009, 02:23 PM
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Tim_B_172 Tim_B_172 is offline
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Default Re: ultralight/moped anyone?

You're right HoughMade, The materials they use for those human powered machines are expensive. Composite construction is of particular interest to me. I am by no means an expert in the subject but I have done a lot of work with fiberglass which is relatively cheap. Mainly just experiments and building things for my own enjoyment including a fender and headlight for my bike. However the human powered planes like the Daedalus were made with a lot of carbon fiber which is a lot more expensive than glass and more difficult to work with. They also used a lot of polyester fabric for covering flying surfaces. That stuff takes a special touch to do it just right. I for one still think that it might be possible, but I don't think that I could build anything light enough.

Justthisguy, if you do make an attempt at this, please keep us informed. I think most of us would be interested and maybe we could offer some pointers along the way.
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Old 09-10-2009, 05:44 PM
FlyJSH FlyJSH is offline
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Default Re: ultralight/moped anyone?

consider the following weight to hp ratios:

Piper Cub: 19 lbs/hp
Grob G109 (motorglider): 21lbs/hp

so if our engines produce 2-3 hp, you might get a 50 lbs glider in the air

Whatever you decide, do NOT try to teach YOURSELF to fly in an UNTESTED aircraft. Test pilots have thousands of hours and extensive special training.
You gotta be smarter than the tool you use.
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Old 09-10-2009, 05:49 PM
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2door 2door is offline
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Default Re: ultralight/moped anyone?

As for the gentleman who said he knows more about aviation than any of us....well, I'm not here to argue but I did my time in the Air Force, did a little commercial stuff afterwards and I have a couple of hours hauling cargo around the Caribbean. I think its safe to say that I too know a little about aircraft and aviation in general. What the young man is venturing to build is, a bit dangerous, questionably useful and unique in design, but it's not impossible. Expensive? Somewhat, given the engineering and materials that would need to go into it. Its the kind of project that maybe a university or a well funded private organization might undertake but probably out of reach today for a high school student working on his own. I'll be the very last person to tell him to forget it. How many times in history can you think of that pioneers in various fields have been told that, ridiculed and shunned by so-called experts. My advice would be for him to garner all the aviation knowledge he can get while he's young, throw in a little engineering and design experience and to not give up on his dream, if that is in fact what it is.
Good luck, young man. And let us know if someday that motorized bicycle/ultralight leaves Mother Earth. I'd personally like to be there when it does.
Age and Treachery Will Always Triumph
Over Youth and Skill & "Charlie Don't Ride"
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Old 09-11-2009, 04:16 AM
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BarelyAWake BarelyAWake is offline
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Default Re: ultralight/moped anyone?

For anyone curious, the weight restriction (USA) for a legal ultralight aircraft is 250lbs dry (safety equipment like a ballistic recovery chute is exempt frm this) so any of the legal ultralights you see weigh that or less.

Yet this doesn't mean yer limited to the flying lawnchair style like my ol' MX, the following (complete w/bouncy landing lol) is a Fisher 202 Koala ultralight made from spruce and dacron (newschool wood & fabric) and has just a 250cc single cyl

YouTube - fisher FP 202 koala ultralight

Now while not as small an engine as the china girl, still... it shows whats possible, I had some stick time in a friend's Koala and it was a fine flying machine. I did wish for more climb, but I'll admit I was a climb ratio fanatic as there was more than one treeline that would try and ambush me as I innocently chased the local geese, did strafing runs on oblivious cattle, and generally trying to annoy as many golfers as possible

The closest to the china girl engine capabilities I've been able to find so far while still limited to "normal" construction materials are some of the earliest ultralights, foot launched and sporting 10hp(ish) chainsaw motors, like the Easy Riser;
Easy Riser ultralight, ultralights, ultralight aircraft, light sport aircraft.

Very similar to the first powered ultralight offered for sale as a kit, the Icarus II. John Moody of Brandon, FL is widely recognized in the industry as the "father of ultralight". In a foot launched McCulloch 101 powered Icarus II hang glider on July 27, 1976 John was the first to demonstrate ultralight aviation at the annual EAA fly-in convention in Oshkosh, WI.

While functional and with acceptable flight characteristics, the restrictive laws at the time were later changed to allow for landing gear and larger engines (greater weight) as to increase the safety margin on these very minimalistic machines. We've moved on to much safer designs - much respect to these pioneers for showing us whats possible!

The sport of foot launched powered hang gliding is alive and well BTW I just never got into weight-shift flying, here's a good place to start though;
Powered hang glider - Wikipedia, the free encyclopedia

Last edited by BarelyAWake; 09-11-2009 at 05:01 AM.
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Old 09-17-2009, 12:42 PM
passivepsycho passivepsycho is offline
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Default Re: ultralight/moped anyone?

Hi, I'm new to this forum but thought I could kick in my two cents. I'm not an expert pilot by any means, and I may not have thousands of hours of stick time but I do have a pilots license and have spent a some time flying an ultralight. I also attend one of the top engineering schools in the country and my thoughts on the subject are this, I doubt it's possible to use only one moped engine to get off the ground, but as long as your designing and building it yourself, why not use two. One push and one pull should do the job if you keep the weight down. I am forming my own ultralight design team on campus and this is one of our major hurdles. We considered electric bicycle motors but all the ones we came across that were even close to able to do the job were too expensive and the batteries way way way too heavy. All the rest are Chinese knock offs of the originals and barely function. (few hundred dollars down the drain). That's when I considered using a gas engine, but one simply wouldn't do the job. They are however light and reliable enough to use two without much trouble. Everything's still on the drawing board but it seems to be coming together nicely. Don't give up man, anything's possible you just have to want it bad enough.
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Old 09-17-2009, 02:04 PM
lokerman lokerman is offline
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Default Re: ultralight/moped anyone?

I haven't read through all the replies to the original question, but I can provide some basic answer here, as I used to own and fly a powered paraglider. The small bicycle engines we use aren't powerful enough. It's not the size, but the power of the engine that counts, and as you know there are vast differences in power between different engines that are the same size. The other big factor is the type of wing, and how efficient it is and how much lift it can produce. I used a 172 CC, 20-25 HP engine to fly a 28 square meter wing and the combined weight with me and the motor was about 220 lbs, the wing another 15 pounds. Now that wing was extremely efficient, but it costs 3300 bucks. I also was going for thrust since that's what that sport requires, so I used a 4 foot propeller and a reduction drive.

So basically, it seems that what you have in mind is not feasible, and most importantly, and I say this from experience, not safe, unless you were to consult experienced pilots. I have known of several deaths in the circles I flew in, and those were people being very safe, and knew all about the weather, and the atmosphere(lots to know there, I thought I knew a lot about it until I started to fly). So if you ever do get anything with enough power and wing to get into the air, safety must be paramount. I hope it doesn't seem like I'm talking down or anything as we're all adults, it's just my experience that makes me cringe at the idea you have here. There are a lot of people who were do-it-yourselfers in my sport, and paid dearly with pain, injury, or death, for not training properly. Well I hope I was of at least some help. If you're serious about flying, there are plenty of enthusiasts to help you the right way. Good luck.
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Old 09-17-2009, 11:41 PM
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hiker472 hiker472 is offline
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Default Re: ultralight/moped anyone?

I wouldn't go with the china engines for any attempts of lift off, but would look into possibly two morini engines, only because they are more reliable and put out more horse power.

The lighter a guy is, the smaller the plane can be, I'd think.

I once knew a guy who had installed two very small motors on a hang glider with just enough fuel to get him in the air and off he went. How much does a hang glider weigh with two motors? He did it and he weighed around 180 and wore winter clothing for the ride.

Seems plausible that any of us with a little will to do and thrill to seek could pull it off too!

Don't feed the bears....
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