30' of foam! [Archive]

FairlyFaded

Mar 24, 2007, 01:46 PM

Hello again everyone.
I have been gathering supplies over the last few weeks, carbon, glass, electronics etc and now its time to start up the thread again. I dont plan on starting the build till next week (spring break) but untill then i will be working more on the design. Anyways heres some pics of what i have so far. Ill be picking up the two sheets of fomular 600 next week. Does anyone know what the density of fomular 600 is? 2lbs? 3?

I think i am going to recap some of the stuff from the last thread in this one in time. Anyways, i have a few ideas that i want some thoughts on. Before i was planing on putting a wood spar cap on top and bottom of the spar, now im thinking, ditch the bottom one because carbon under tensions not going to damage the foam. But for the top im thinking have foam. Then vac bag the layers of carbon ontop the top, then bag the wood spar cap ontop of that. It seems to me like this would make the carbon almost under tension instead of compresion. Also for the carbon to buckle, it would have to push into the foam and rip the glue joint off of the wood, seems like having the carbon sandwiched on both sides would work very nicley...

Another thing, does anyone have any ideas on a nice slow airfoil to use and how i should go about printing it (8 sheets glued together?) thanks!

michael

SoCalGliderFlyr

Mar 24, 2007, 06:09 PM

Death Wish Version Two.

FairlyFaded

Mar 24, 2007, 06:55 PM

lets not get into that again....

SoCalGliderFlyr

Mar 24, 2007, 07:05 PM

Don't worry. I wouldn't get into anything you designed and built! I doubt that anyone in their right mind would either.

flystoolow

Mar 24, 2007, 07:15 PM

There is something a little silly here:

The thing is, most of us in this forum love flying. It would really bother us to waste huge amounts of time and money without any flying time in return.

If you want to get off the ground and skim along for a few meters, of even a hundred yards, a very large tarp and four ropes will do the trick on a windy day.

On the other hand, if you love the thought of flying, and want to fly, it would take you one week and only a few hundred dollars to get full time paragliding or hang gliding lessons, and begin flying from mountain tops. You can buy a decent used wing of either sort easily for $1000, and fly, and thermal, and soar for hours....and yes, it is just about the best feeling in the world.

If you want a mortorized plane, both paragliders and hang gliders can also be used with motors.

Of course if you love building, and don't really care for flying, then you are on the right track (notice how the word track refers to something usually found spread out on the ground ;) ).

All this complaining is in jest, as it is still winter in most of North America, and the majority of us would really like to see all your build photos like those you documented VERY WELL on the last plane. Never mind what it is, we love photos during the long dreary evenings.

Can't wait for the photo of you soaring at 3000' with the eagles.

Heck, even one at 3' would be interesting.

flystoolow

Mar 24, 2007, 07:27 PM

Let's sweeten the pot a bit: :)

I'll send you $1 if you fly this machine over 200 meters and go directly home afterwards (not to the hospital on the way home).

Anyone else in for a buck?

soarrich

Mar 24, 2007, 07:43 PM

If my butt was going in this I would find an ultralite forum to get people who have more knowledge tempered with their butts on the line.

Dead is forever.

FairlyFaded

Mar 24, 2007, 07:46 PM

lol, i see what your saying flys, for me building is really what i like doing- I like flying but building somthing from my own design i find to be much more rewarding (at least for rc planes). Also if this works it will be much more then just a paraglider, it will be very one of a kind. Thanks for the compliments on my build pics, Ill do the same thing for this build, should be alot cooler though because ill be bagging most of the parts (spar,ribs etc) and boy do bagged parts look cool....
How do you guys think the AG36 airfoil would work? i could thinken it to maybe 11%... it has a nice D box/covering friendly design.

Michael

P.s. flys-if 1/5th of the people who looked at my last thread pitched in a dollar, id probably come out even! :D

schrederman

Mar 24, 2007, 11:30 PM

I'm not trying to be rude, but this is a man-carrying craft, and I believe your thread is misplaced. You should be posting on an EAA forum where others building man-carrying craft can help you out. I wish you teh best with it. Me, I'm a little chicken, I guess. I would prefer 500 pounds of carbon fiber, epoxy, and fiberglass that's capable of 143 knots... Lots of jokes being thrown around, but flying is a serious business.

Be careful

Jack Womack

FairlyFaded

Mar 25, 2007, 02:04 AM

I have never found a forum that has more smart people with good ideas then this one. The idea on this plane is to make it almost like a scaled up rc plane. Also i would not be surprised to find my thread/ideas getting shot down real quick with no explanation on a different forum.
michael

Ollie

Mar 25, 2007, 06:37 AM

FairlyFaded,
Smarts (youth) is not enough. Wisdom (old) is not enough. For this project you need both smarts and wisdom. Control your ego. Timing (old and youth) is important for your project. Join a team like EAA. You can learn faster with a team.

SoCalGliderFlyr

Mar 25, 2007, 12:50 PM

I've just nominated FF for the Darwin Awards.

FairlyFaded

Mar 25, 2007, 01:41 PM

does anyone have any thoughts on wether i should put the carbon under the wood spar cap or ontop with the glass running over it?
Michael

luger007

Mar 25, 2007, 02:20 PM

Michael,
Not sure why you are asking these guys in a model forum for advise on your full scale plane, you seem to have it all pretty well figured out. I like your drawings, looks like a scaled up DLG of sorts. Post more pics when you can and I think it will be an absolute MUST to have any flight footage posted when you get some. BTW, do you plan on putting a balistic chute in your machine? I know from flying ultralights they are a REALLY good idea. I personally enjoy flying, anything. From models to real Cesnas and Cherokees. I usually fly (full scale) down the coastline, mostly for the view from 2400' but it's also putting in time towards my pilots license that I may get some day. Do you plan on getting any flight lessons before taking your craft into the wild blue yonder??

Best of luck and keep posting
Matt

schrederman

Mar 25, 2007, 09:45 PM

I can't imagine anyone wanting to give advise because of possible liability problems later. That's why you need to be dealing with EAA folks. They have all that pretty well worked out. I was a good EAA member for 10 years while I built my HP-14T sailplane.

Jack

seanpcola

Mar 25, 2007, 10:21 PM

I have been involved in full scale (certified and homebuilt) and models a long time and I think FF should seriously heed the advice of these other guys, IE, join EAA, get some full scale guys involved AND plenty of flight time in a proven design. I have known too many people that are no longer with us due to some really small glitches in design, construction and/or piloting errors. Your design, FF, looks way cool but most people cannot imagine how small a gremlin it takes to ruin your whole day.

Ref: Your post # 10

I think you would be surprised how helpful EAA guys are. No one (at least that I have ever met) frowns on new and innovative ideas. I do not believe you would be "shot down". You will get more advice and opinions than you may want but one thing you have got to be open to in this endeavor is critisism. It is not put out there to make you look bad, it is there to help you be succesfull and not auger in. Remember, all of these homebuilt guys have something at stake in keeping accident records down and their collective success rate up.

Phoebusflyer

Mar 25, 2007, 10:21 PM

FF, I'll give you a nickels worth of free advice, DON'T DO IT!!!!!!!!!!

FairlyFaded

Mar 25, 2007, 10:24 PM

Hummmm, Well let me say this, neither my parents or i Will hold anyone responsible if anything goes wrong because they gave advise. Its just not in my nature nor my parents. So please if you have somthing to say about the design say it! my plane will have a better chance of sucess that way anyways.... About the EAA and such, I think you guys would be just as good. A spar is a spar no mater how large it is, and same with loads and carbon etc. My question about the spar isnt very complex.... Im sure there is somone who has tried what im saying, if you have pleases chime in.

heres another idea for a spar cap that i like. Get some 1/8" contest balsa. connect 4' strips to make the needed 10' length. Then bag the 2-5 carbon layers ontop of the balsa. Then bag another layer of balsa ontop. Then bag bias glass over the whole thing..... It seems this way i could actualy get close to 100% of the carbons true compression strength because it would have a very hard time buckling. any thoughts on this?

I have been toying with the chute idea. If i start taking it above 10' (which if it works and works well i will do) Then i willl defenetly want some sort of a chute. I have read about chutes you throw like in the goat glider... Does anyone know anything about them? What would be nice is if i could have a chute that i keep on my lap or on my chest that i could toss out of the fuse if say my elevator link breaks. It would then open up, slow my forwards speed and then just start slowly dropping. The question is wether it would open at only 26mph.... Anyways i hope somone can chime in about my spar caps. thanks

michael

Sean- How should i go about contacting/geting help from EAA? I would be worried that they wouldnt want to help me because they think im just some kid who wants to fly.... maybe it would be worth a shot?

seanpcola

Mar 25, 2007, 10:32 PM

http://www.eaa.org/

schrederman

Mar 25, 2007, 10:34 PM

It's one thing to guess when it's just R/C stuff. People that design man-carrying airplanes go to great lengths to work out the strengths needed and materials to be used, most often with pretty big safety margins. So, now, there's your advise on this design. It looks cool but you have no idea as to whether any of your spar designs will carry your weight and withstand a 30 mph thermal gust while doing it. Please understand, no one here is trying to put you down, other than So Cal, maybe, but he's not really. We're only concerned that you will hurt yourself or worse. I'm with Sean. I've known several people that have died in ultralights and hang gliders. Please put your ego aside and get some help from those that have as much to lose as you... their lives. Join EAA.

Jack Womack

seanpcola

Mar 25, 2007, 10:42 PM

Sean- How should i go about contacting/geting help from EAA? I would be worried that they wouldnt want to help me because they think im just some kid who wants to fly.... maybe it would be worth a shot?

The last thing these guys would think is that you are just "some kid". Their organization is very much dedicated to helping young people get started in aviation THE RIGHT WAY.

Having said all of this, I, again, want to say that before you get started, you need to allow people that know what they are talking about help and guide you in this including learning how to fly, THEN on to design and construction. This whole process that you are contemplating is a long and hard road. Not to discourage you, but it ain't as simple as scaling up a model. Spar construction, for example, does not always apply between model and full scale. Air foils, moments, balance, the whole nine yards has many, many different considerations between models and full scale. Add to that the fact that with RC, if we mess up we just go home and start over. In full scale, the most minor of mistakes will cost you everything!

FairlyFaded

Mar 25, 2007, 11:48 PM

With the help of an aero astro friend of mine at stanford i learned how to calculate loads etc on a wing. I know full well how much carbon i will need (actualy i know how much carbon will be PLEANTY, and im going to use that much). I hope somone can also learn a bit from these.....

michael

p.s. eaa membership 40$ for a year.... hummmm......

p.s.s. there are more saftey margins in my calculations then in a roller coaster.

sekollera

Mar 26, 2007, 12:20 AM

Stop trying to design a plane and be a test pilot.

Build to a good plan or kit instead. A Carbon Dragon will keep you busy for years and is a proper soaring machine that flies wonderfully in the lightest lift - in many ways it is cutting edge.

http://www.carbondragon.us/

It is more "model" than "full-scale sailplane" and looks a bit like your design, except the wings won't fall off!

I once had the dream too. "I'm gonna build me a full scale sailplane!" Looked into all the kits out there, considered the time needed, talked to builders. Fact is, gone are the days of Scweitzer 1-26 kits that some scouts could assemble. HP kits can be found, but they not recommended for low time pilots. And consider the 1500 plus hours to build such a plane. A way out of this is to find a partially completed kit. There are lots out there, ever wonder why?!

I've personally help assemble Steve Arndt's CD last summer and must say it is very neat piece of kit. And his enthusiasm for homebuilding is infectious!

/Adam

FairlyFaded

Mar 26, 2007, 12:30 AM

tell me the flaws you see in my design and i will try and fix them.

sekollera

Mar 26, 2007, 12:35 AM

3G?

GA planes typically use 5-6G positive, information that $40 to the EAA would buy you.

Adam
Jantar Std with +9/-7G wings and 154kt VNE...

Sensiblenick

Mar 26, 2007, 04:24 AM

tell me the flaws you see in my design and i will try and fix them.

So so so so many.

You have advice here from people who are qualified glider pilots and experienced designers. Thier advice is to quit while you're alive.

My advice is to read up on all the deaths that occur when experienced pilots use tested and proven machinery... Then remind yourself that what you are proposing to build uses a construction that many model pilots and builders would consider to be "sub standard" and nor are you an experienced pilot.

People here are wisely suggesting that you join a group where people are experienced in this sort of design... DO IT.

However... Charles Darwin would be proud of you; Continue upon this mis-guided adventure, and you'll most likely prove his theories in a most wornderfully messy way:

Make sure you fill out an organ donor-card before your test flight, but make a note that "brain activity" was at a low level before any accidents happend anyway. ;)

samotage

Mar 26, 2007, 06:39 AM

Whaddaya mean Nick?

There is more margin for safety in those calculations than a roller coaster ;) I suspect you are a little envious of all that carbon.

MTT

Mar 26, 2007, 07:22 AM

There are 2 mistakes in your calculations in post #22

First, as already pointed out, you have to design to more than 3g.

Second, how on earth are going to realize 200 lbs AUW ?
Remember that in the case of man-carrying flying machines, the weight of pilots, passengers, cargo, fuel, etc., is part of the AUW. So, 200 lbs AUW is way too low.
I don't know how tall & heavy you are, but if you are an average sized guy, you will weigh, say, 180lbs.
You don't really think that you can build an airframe this size at 20 lbs., do you ?

Phil Barnes

Mar 26, 2007, 09:24 AM

Michael (FairlyFaded) is a 15 year old kid that weighs 110 pounds. This is at least the second thread he has started on this topic. He terminated the previous thread (http://www.rcgroups.com/forums/showthread.php?t=645386) when a static test of his partially completed center section failed a wee bit early.

Michael, You have taken a big step in the right direction by actually using calculations to determine a proper structure for your spar. It is also a good idea to talk to and LISTEN to actual aero engineers and structural engineers about your design. So you have a taken a couple of baby steps in the right direction. That's a start on what needs to be a very long journey if you are ever to build a safe man carrying aircraft. There will be MANY reality checks along the way if you listen to the words of caution that are offered by people with vastly more experience than what you have. MTT pointed out two such reality checks in the last post.

I noticed that you used some data from my weblet tests in your calculations. Please DO NOT use any information or data that I have posted in the design of your aircraft. I am not an engineer of any type and my knowledge should not be relied on to design any man carrying aircraft. If you had the proper mind set of an engineer who is designing a man carrying aircraft you would have noticed that the skin thicknesses used in my calculations were GUESTIMATES and the primary purpose of the tests was to compare one type of skin structure to another, NOT to calculate the actual load carrying capability of any particular structure. You should know that I built some test panels of MODEL AIRPLANE wings and tested them to failure. All of the test panels failed at a load considerably lower than what would have been predicted by theory using calculations such as you have used and skin thickness data taken from the earlier tests in my weblet thread.

Another reality check is that you need to calculate the shear loads on your spar system. I am not sure if you have any proper conception of what a shear load is at this point though. In reading your previous thread you frequently demonstrated a totally misguided idea about what a shear load on a spar is. The problem is that many of the people offering advice to you in that thread were just as confused about what a shear load is as you were. You cannot design a safe aircraft structure by getting advice online from people who you don't know and who may or may not know what they are talking about. You would need to have a complete structural design certified by a proessional who is in the business of designimng aircraft structures. You need a bit more than anonymous advice from model airplane guys who you have not met.

The shear load in question here is the load that tends to make the spar caps slide past one another in a spanwise direction. In your previous thread a poster named Ollie attempted to direct your attention to a series of articles that described shear loads on spar systems. Your response (http://www.rcgroups.com/forums/showthread.php?p=6978311#post6978311) clearly indicated that you did not understand the material and yet you moved right along as if it was not important. It should be of interest to you and a valuable lesson to you that your first wing panel very likely failed due to a shear failure of the spar. The lesson to take from this is that you do not yet know what is important and if you continue to try and design this aircraft by taking advice from a model airplane forum then will never have any way of knowing whether you have persued bad advice or if you have blown off good advice.

The best advice you have been given so far is to join the EAA and follow their guidance on how to design a safe man carrying aircraft. Your only response is that it would cost you $40 to do that. Do your parents know that you are designing and building an aircraft that you intend to get inside and fly? Have they been reading these threads in RCgroups? Do they know that you will not get advice from qualified people because it might cost $40?

Ralph Walton

Mar 26, 2007, 10:15 AM

Please FF, the $40 is cheap compared to your life (or the carbon your planning on throwing at this project)
You are an intellignt guy, but this is is not a smart idea. Get out NOW before you get an unreasonable desire to continue.

I have 25 years of mechanical engineering experience, incuding design, behind me. A bunch of other experienced guys have aready contributed as well. There is a common theme. Don't attempt this with your level of knowledge and experience. The consequence of failure of any of the systems is death. You don't have to be flying very high or fast to kill your self.

If you must continue, build a kit glider of known design and performance, and learn to fly with flying lessons. Amongst other things you will learn there is safety in height. Not safety in keeping close to the ground and gradually working your way up.

Don't be discouraged. Your energy, enthusiasm and skill just needs to be redirected.
Ralph Walton

Ollie

Mar 26, 2007, 10:24 AM

Phil,
You are a great communicator!!!!!!

FairlyFaded

Mar 26, 2007, 11:47 AM

I do understand shear loads on the spar as shown in that article. The lack of glass on my old spar holding the spar caps in place (keeping them from "sliding" off) was the reason for the falure, i was preaty sure this would happen but due to a bad design i couldnt/didnt really want to glass it, This time around i am going to be using fomular 600 (way stronger) and i will have 45/45 glass wraped and bagged around the whole thing. I will test a section of the spar and see which part breaks first, then beaf that section up, hopefully it will be the carbon, we will see.

Anyways i am at school right now so i cant reply in full to other comments, more to come.

michael

p.s. I am NOT stopping, The chances of sucess for me are well worth it. With that said i plan on doing this as well as i can, but there no question about wether im doing it.

Jeffrito

Mar 26, 2007, 12:11 PM

How do you guys think the AG36 airfoil would work?

Terribly, because it was designed for a specific usage; small, lightweight RC sailplanes. You don't just pick an airfoil out of the air & expect it to work.

Here's a book I'd recommend to you, if you seriously want to learn how to build a sailplane you can fly in, rather than doing it by trial and error, which could take a lifetime & more money & carbon fiber/foam than you could ever buy:

Fundamentals of Sailplane Design (http://www.cgpp.com/gr.html)

It will only cost you $50, but the lessons learned will be priceless.

Jeff

Sensiblenick

Mar 26, 2007, 12:23 PM

p.s. I am NOT stopping, The chances of sucess for me are well worth it. With that said i plan on doing this as well as i can, but there no question about wether im doing it.

You know... Dying isn't so bad. :rolleyes: The bit you want to look out for is putting yourself into a vegetative state or a wheelchair. That'll make your parents and yourself wish that you'd heeded good advice and Joined the EAA, and actually studied a few things.

Currently you appear to beblindly throwing Carbon Fibre and other exotic materials at a poorly concieved plan in the hope that the mix of high and low Tech will come to a happy medium.

As many others have pointed out, you're asking smart people for free advice, then throwing the majority of it back in thier faces. You're looking a gift-horse in the mouth... and then returning the gift.

If you truly want to do this to the best of your ability.. FOLLOW the advice and join the EAA: It'll cost less than a roll of Carbon fibre, and might well save you the use of your legs.

flystoolow

Mar 26, 2007, 01:30 PM

A lot of talk here about a complicated spar, but it does not need to be complicated to be strong.

Your wood cap strips on the last wing were much too small in cross section.

Have you seen the "modern" floor joists at a lumber yard? They are I-beam construction, and the cap strips are are about 2" X 1" in cross section. They can span something like 16' and carry a very large load.

I am not suggesting using a floor joist as they are too heavy, but a light version with similar dimensions will support around 600 lbs over a 10 foot span if prevented from twisting.

artmonster

Mar 26, 2007, 03:32 PM

Hey FF....

this design would fair well as a catapult launched glider. ( could easily make the catapult out of lumber and old car leaf springs.)

or especially RC turbine thrusted ( but that costs a little more than $40.....and it was allready done by that crazy fly guy )

...........

sand it round.

Rip the bring.

steve wenban

Mar 26, 2007, 03:49 PM

Rip a foil into it and make it brick ;)
Kid While I admire your enthusiam , think about it carefully all these guys have given direction and advice that you just couldnt buy , if you want to build something build a large scale model of it that your not going to put life and limb on the line. If your so determined to fly join the air league and do it right . Dont risk your life and your families lives by being a smack ..
SteveW

FairlyFaded

Mar 26, 2007, 03:56 PM

This thread is heading in the same direction as the last, Im hearing a whole ton of people telling me what not to do (or im going to die) and only a few telling me why not to do it.

I will join the EAA, i hope there forum area is worth it :D
The fact is- I am reading all of your ideas and taking them into consideratioin, i value all of them! my last thread tought me tons of things about spar design! To be honest i think i have only goten maybe 3 sugestions so far out of this thread, and i have considered each one.

anyways- Flys, im thinking about using 2" strips for this one, i dont think i will need much more surface are because the combo of fomular 600 and the bias glass should keep the spar caps in check. Again all this will be seen in the test spar.

Sinsible nick- I have notte thrown a piece of advace back into anyones face or away. When i posted the 40$ comment i wasnt saying oh this is to expensive i was saying i will consider it.
Also keep in mind the personal jibes are mildly funny but not very productive.
One last thing nick, you quoted me on "tell me the flaws and then ill fix it" at the begining of your post, Funny thing is is you didnt come up with a single flaw in my design, you just told me i should join the EAA.

I have a question. What would a good way of testing a say 5' section of my spar to falure be? Maybe the method drella/barns uses? Im asuming i could use long legs to increase the leverage so i could mimic 600lbs?
Or should i instead make a section in the same design as my realy one but make it 3"'s tall instead of 6" so that id have to use half of the wieght? Any ideas help.

Jeff- I really dont know much about airfoil design, i just tossed that one out as an idea. I may look into getting the book you mentioned, but for now could somone please link me to a place with airfoils to start with? I dont think it would be very hard to find a nice low speed (25mph) high lift ultra light airfoil, i just havnt come up with any through my searches, thanks!

michael

p.s. Flys- its funny because a 2-4 would probably do for a spar, Of course it is alot heavier. From what i read carbon is at least 100X stronger then wood per pound. So my goal is to mimic thouse large wood spars but make it say 1/10th of the weight.

p.s.s. Phill- your calculated numbers i think should work fine for my uses (rectangular spar). Keep in mind that true the skin thickness is sortof a guess but its all relative. My carbon is rated at .014"s your calculations are based off of numbers much like that (.007"'s for 4oz aprox). Once again we will see with my trial spare....

steve wenban

Mar 26, 2007, 04:56 PM

Its all been said , But you want to continue well good luck and I hope you survive .You have the makings of a good airframe mech ,just dont throw it away on 1 half baked idea . And if you want airfoils try here.
http://www.ae.uiuc.edu/m-selig/ads/coord_database.html
SteveW who's in the industry ,still saying dont do it

screamin' eagle

Mar 26, 2007, 05:01 PM

I think you should go ahead and do it. At least it will spare us from having to endure your next "big idea."

Sensiblenick

Mar 26, 2007, 05:24 PM

I didn't answer your plea for design advice for many reasons: Chief among them is this: Although I'm an engineer with a fairly large amount of experience, I am far from qualified to tell a child how to make a man-carrying aircraft.

For that reason, I, Like MANY others urged you to join the EAA. The slope forum now has a little thread following your progress on this one: Someone has wondered out loud if you are aware of the big difference between aero-modellers and "real" pilots... The main difference is that we walk TOWARDS our crashes.

It's been said before... you appear to have one hell of a lot of drive, ambition and resources.. I (and I'm sure many others are too) am very glad you see that you're going to spend that $40 and get your toe in the door where people with experience might be able to help you... but when they say they're not willing to help you on the grounds of liability etc... please do respect it... unlike you appear to be doing here:

I noticed that you used some data from my weblet tests in your calculations. Please DO NOT use any information or data that I have posted in the design of your aircraft.

Phill- your calculated numbers i think should work fine for my uses (rectangular spar). Keep in mind that true the skin thickness is sortof a guess but its all relative.

Good luck kid :)

MTT

Mar 26, 2007, 06:26 PM

Im hearing a whole ton of people telling me what not to do (or im going to die) and only a few telling me why not to do it.

Well, I did tell you that your wing (or spar) is way under-engineered, and why, and we haven't heard any comment from you on that.....

All we hear from you is complaining, because the advice from guys who have a lot more experience from you in designing stuff like this, doesn't fit into your dream world...

FairlyFaded

Mar 26, 2007, 06:53 PM

thanks for the link steve- i have been to that site, im just not sure otu of the some thousand foils which one would be good. I see a fair number of "ultralight" foils, but which ones will do the trick?

MTT- I did take what you said into consideration, keep in mind my calculations are probably more like 5g due to saftey factors. Also if i achieve the 160lb gross weight then even higher. I think i will do some acurate calcs for a 160lb plane under 6g and see what i come up with.

Phill ill take out my mention of you in my post....

michael

samotage

Mar 26, 2007, 07:12 PM

FF,

Have you considered some of the trends of asymmetrical airplane design? Bluhm and Voss had some magnificent flying boats under development. I think you could learn much from their prototyping work.

artmonster

Mar 26, 2007, 08:11 PM

OK...all kidding aside FF.

I think we all had a good laugh...and it's not mean spirited directed at you personally....it's just that we have seen it before.

There have been a lot of good resources given to you for knowledge gathering for your project......Please use them...you will be pleased you did in the long run.

Here is one thread I found on proper ways to build large RC planes. Joe Manor is a Wizz when it comes to these big babys. Carbon testing (http://www.rcgroups.com/forums/showthread.php?t=480273).

Look how he does it, and then you can see what it takes to make a large plane structurally sound.

He does amazing things with composites that I think you'll like.

I love this thread, as well as the last one you did.

You have great skills in producing the various components of your aircraft, but there is a whole lot of aspects that go into it.

My advice is to make a small scale of the plane you invision....fly the hell out of it....Put it in CaDD so you can tweak the design for multiple prototypes...so you can first hand see what dirfferences the design changes make in actual flight.

Then when you are satisfied....make a bigger version......maybe the size similar to what Joe manor built...then fly the hell out of it and tweak it.

Then (and I hope you are part of EAA when you start this endevor...so you can be constantly gaining knowledge about designing), and only then......try a full scale prototype......then fly the hell out of it...

And if it handles all the stress tests and tweaks you put it through.....Your ready for a real version. ;)
:D

An then you know what??? it will be the best damn custom plane out there, and you will be ableto start marketing it and selling kits........ ;) :D

And then ! you can start the next projecvt that will be a much more ambitios one......and you can use all of the knowledge that you gained in the processs of the first one that was destined to be a success.

FF....don't get discouraged, or try to rush a grand idea.

Do it right, and you will be the greatest aeronautical engineer this century has ever seen.

I'm impressed with your drive and knowledge that you have allready. Show all these yahoo's in RCGroups that they are wrong about you....and build the next generation of flying machines......Just don't try to do it overnight....

"remember....knowledge is power".

:rolleyes: ;)

artmonster

Mar 26, 2007, 08:23 PM

oh......

p.s. Do you have any photos and/or descriptions of planes RC or any type that you have built allready and are flying FF?

I'd be interested to see your building skills on them.

If you are ambitious enough to get to this stage of the game, I'd like to see some of the things you allready may have made. :D :D

What's your favorite type of RC?

Mine is slope, then thermal, then electrics, and Im starting to get into small heli's......(I used to fly glow, but lost interest wit hte mess and having to go to the flying field to fly..that's why I went electric).

What kind of RC sparks your interst the most?

My most ambition project was a scratch A4 Skyhawk 'Blue Angel' sloper out of EPP....I havent even started in omposites......so Im behind you in that skill, and I have 25 years on ya. ;)

infopimp

Mar 26, 2007, 08:36 PM

I've checked out until I see a change in attitude. FF, you don't even see how you are coming off to everyone!

I wonder if, after your crash, with Stephen Hawking controls on your wheelchair, you would still be snapping back at everyone about how you just need to tweak the design.... peck peck peck peck

MTT

Mar 26, 2007, 08:57 PM

MTT- I did take what you said into consideration, keep in mind my calculations are probably more like 5g due to saftey factors. Also if i achieve the 160lb gross weight then even higher. I think i will do some acurate calcs for a 160lb plane under 6g and see what i come up with.

What safety factors?
The only "safety factor" I see in your calculations in post #22, is that you assumed a maximum load of 3 g = 600 lbs.

Pardon my french, but in this case "assumption is the mother of all :censored: ups " applies....

First, as already mentioned, 3 g is not enough.
If it were 5g, as you say, you would have to calculate with a max. load of 1000 lbs.
But now i come back again to your AUW, or gross weight...
In you first example, you calculate an AUW of 200 lbs, which is impossible, as already explained.
And now you talk about 160 lbs gross weight....
I'm not quite sure, what you mean by gross weight....
Normally,"gross weight" is the weight of the aircraft, ready to fly, with pilot, passengers, cargo, engine(s), fuel, oil, misc. equipment. (whatever may be applicable)
In your case, with you weighing in at 110 lbs., as Phil wrote, you would have an airframe weight of 50 lbs, or 90 lbs, if we go with the 200 lbs. AUW.

To give you an idea what you are up to:
The Gossamer Albatross( http://en.wikipedia.org/wiki/Gossamer_Albatross) , built by Paul McCready, was designed to cross the english channel, powered only by a human pedaling.
The albatross is about as light as you can build an airplane, I would say. And McCready and his crew had materials, money and know-how available, of which we can only dream, and still his airframe weighed in at 71 lbs.

AUW (airframe +pilot/engine) was 220lbs.

Phil Barnes

Mar 26, 2007, 09:27 PM

Similar weights for project Daedelus (http://en.wikipedia.org/wiki/MIT_Daedalus) .

jrerickson

Mar 26, 2007, 09:54 PM

Nice 3 view...drawn by none other than Dr. Mark Drela. Note spar was a carbon tube. Airfoil was "DAE 11", very thick, nearly flat bottom.

http://web.mit.edu/drela/Public/web/hpa/daedalus.tif

John

FairlyFaded

Mar 26, 2007, 10:05 PM

Here are a ton of photos (to many really) of some of my planes. I dont have pictures of a fair number of my creations : ( but this should give you an idea.
This is a link to a DL50 build thread i did
http://www.rcgroups.com/forums/showthread.php?t=413458
It was my first wack out vac bagging, I hope the photos are atleast kindof cool to look at.

One thing to keep in mind is, i went from flying paper airplanes and little things, barley being able to use a skill saw-to this in maybe 6years, my learning curve is preaty big....

John_R_C

Mar 26, 2007, 11:01 PM

I don't know where to start, but here's a copy from the EAA Members Only portion of their website discussing Technical Counselors:

quote - EAA Technical Counselors: An EAA Technical Counselor is an experienced volunteer advisor who shares knowledge and expertise to aircraft builders. These Technical Counselors are part of the "member helping member" tradition of EAA. They advise builders on constructing a safe, airworthy aircraft for final FAA inspection. These volunteers, who offer their services at no charge, are at least one of the following:
Have built an experimental category aircraft;
Have restored an antique/classic aircraft;
Hold an A&P, IA, DAR, DER or Aerospace Engineer rating in the U.S., an equivalent international rating or have the qualifications for those ratings;
In the case of an ultralight Technical Counselor, have experience and ability to provide technical assistance to ultralight aircraft builders.
These volunteers visit projects and advise builders on how to comply with building instructions and federal regulations. Technical Counselors offer tips based on their experience and help builders avoid costly mistakes. Through Technical Counselors, EAA helps maintain the excellent reputation of the amateur-built program. - end quote.

This is the type of help ypu need to address your goal of flying your own airplane. That's why you need to join the EAA!!!!

Also, You will need an FAA Certification following the amateur build regulations. The Flight Standards District Office has personnell who do these inspections before you can legally (much less morally) fly your creation. You will also need a flying license, airworthiness certificate, operating limitations statement, and weight and balance data on your aircraft and more before you can fly.

FAA will also want to see your build log, design limitations, proof testing results, etc. documented to get the airworthiness certificate.

Bottom line is, you don't know what you don't know!

Join the EAA, get in with a chapter with folks building aircraft, ask lots of questions, get hooked up with a Technical Counselor and proceed from there. Don't try to go it alone or expect ful size, man carrying aircraft design help from a MODEL aircraft forum.

John C

corsha99

Mar 26, 2007, 11:27 PM

Please do us all a big favor and agree to hold off on building anything full scale right now that you plan on strapping into. Keep on experimenting and tinkering as that will teach you quite a bit. I am envious that you have the time and funds to experiment as much as you do. Assuming that you are a teenager not in college like the pics lead me to believe, take your enthusiasm and make plans to get a good aerospace engineering degree and get some mentoring from people who have been there and done that. Learn how to design and analyze following processes that people would expect to see and you will probably get a lot more useful feedback.

Jeffrito

Mar 26, 2007, 11:39 PM

a67676767

Mar 27, 2007, 12:16 AM

FF you definitely have some cool planes and ideas. I am with the rest of the guys, though .. don't try building your own plane without getting hooked up with the right people.

samotage

Mar 27, 2007, 01:03 AM

Many people participate in a little home brew free flight craft around the world even! Here are some fine examples of magnificent creations...

JamieL

Mar 27, 2007, 01:09 AM

Well, I've read the better part of your last thread on this idea, and now most of this thread as well.

Being 18 years old myself, I've been in the hobby for four years now, and as you have done, have designed and built several aircraft of my own. I'll admit it's tough when you come up with ideas that seem perfect and people tell you they won't work. It sucks, its happened to me, but its life. You've gotta think that maybe, just maybe the person, or in this case the many people, who say it won't work might know more about designing these planes than we do. Most of them definitely do. Its not to say that we're not smart, just that they have many more years of experience, which is often worth much more than smarts alone. Thats not even considering that the people with whom I am familiar (have read many posts from) who have posted in this thread seem to be quite intelligent people. Odds are they are giving you good advice.

As I mentioned, I have designed and built numerous RC sailplanes. None have been perfect on their first flights. I don't expect them to be, as I am not an aerospace enginner qualified to actually desing these things. Not yet anyway :D I'm off to univeristy next year! Anybody who knows of any flyers in or near Ottawa give me a shout!

One 3 meter RES sailplane I built using built-up constuction comes to mind. To give you a taste of what's coming... its now only a 2.5 meter RES woody. What happened is that after a few successfull flights (man if flew well!! :D) the wing folded on a very light winch launch. Right in the middle. I thought I had enough carbon in there to jump on the thing, and I probably did. It just wasn't utilized correctly. Wing spars are VERY complicated things. Take one look at a university mechanical engineering textbook and you'll be amazed. Then try a fluid mechanics book (which I am trying to read) and you'll see just how many things go into designing an aircraft.

What I'm saying is that my spar failure was due to a single overlooked aspect of the design. Already, many overlooked areas of your design have been pointed out, and rightfully re-assessed, but most likely there are still problems, even though it may seem bomb-proof to you at the moment. When my spar failed, I simply learned from it. It didn't cost me anything. If yours fails, you may not be able to learn anything ever again.

As stated, I too hate it when people rain on a seemingly awesome design, but the grass is greener where it rains. I'm not saying you should stop your build. In fact, I think it is a great idea (in concept), but you NEED to listen to the naysayers who say that your spar will fail. If they are wrong, then so what. But if they're right, then you're in some serious trouble. Take the time to build this thing properly, and with expert help. Build smaller versions. Design a couple big (3 to 4 meter) gliders and build those. Test them hard, and learn from what happens. You should apply your new knowledge on spar design to planes like those before putting your neck on the line. Who knows, you may feel your need to design an awesome airplane is satisfied and leave it at that.

Like I said, I want to see this work. I would be very happy for you if it does. But the last thing I want is to hear of this on the news, and I think it's safe to say that a successful flight would NOT be appearing in the papers. So keep your ears and mind open to people's suggestions.

PS. With that carbon supply you could build some KICK A$% thermal gliders! I envy your supply.

Cheers, Jamie.

JamieL

Mar 27, 2007, 01:11 AM

Ha! Samotage I just saw your post. Great stuff LOL. Truely the wonders of modern aviation... ;)

glderguy

Mar 27, 2007, 01:14 AM

Why keep this thread going, just let him go ahead build the thing and kill himself.
Walter

steve wenban

Mar 27, 2007, 03:04 AM

Why keep this thread going, just let him go ahead build the thing and kill himself.
Walter
I like to encourage kids like this but channel that energy into achieveable goals not sucide missions I sure the authorities would take 1 look at something with 30 feet of span appearing in some local park would definitely attract their attention and said machine test days would be brought to a pretty quick halt. I like the kid I think he's got potential and I'd prefer to see him live long enough to reach it :)
SteveW

artmonster

Mar 27, 2007, 09:27 AM

" Ready are you? What know you of ready? For eight hundred years have I trained Jedi. My own counsel will I keep on who is to be trained. A Jedi must have the deepest commitment, the most serious mind. This one a long time have I watched. All his life has he looked away... to the future, to the horizon. Never his mind on where he was. Hmm? What he was doing. Hmph. Adventure. Heh. Excitement. Heh. A Jedi craves not these things. You are reckless. "

-Yoda

((there's a parallel here...... :rolleyes: ))

satinet

Mar 27, 2007, 09:45 AM

yeah but luke skywalker survived..........

FlyH2O

Mar 27, 2007, 11:08 AM

FF

It is apparent that looking at all of the projects that have been undertaken (post #51), you’re obsessed with flight and are a mechanically inclined person. DON’T LOSE YOU PASSION FOR FLIGHT!!!

On that note your project has promise and merit. You should outline your project and document it well. Start at a smaller scale like 1/3 or less and work your way up! Failures on a smaller scale cost less in the long run!!! Keep track of all of your steps, parts, processes, and testing. Record your successes and failures no matter how big or small.

When it comes time to build a full scale prototype multiples of all key structural components should be made and tested to a catastrophic failure and learn from there failures. My Father was a machine design engineer at a seatbelt and safety equipment manufacture. At regular intervals they would remove random samples and test them to failure and inspect the results and parameters of the test. This was done for every component in an assembly, and if they didn’t meet strict standards the whole lot of seatbelts would be scrapped!!

What you should take from my post is start little and work your way to your dream!!
Get an EAA Technical Counselor and learn everything you can. If they say something isn’t safe or the correct way to do it listen learn and make a better craft. And above all don’t lose the dream and prove the “Neigh Sayers” wrong the right way!!

Larry O

satinet

Mar 27, 2007, 11:24 AM

i don't think that people are naysayers per se - it's just that people know that things never work out perfectly 1st time. and when your life is at stake, then it's not very sensible to proceed. imagine the amount of testing that goes into even the simplest full size plane or glider.

If here were building a 1/3rd scale or something i think he would get a huge amount of support.

sekollera

Mar 27, 2007, 01:21 PM

FF,

You should read this book on the Daedalus project - you will love it.

http://www-tech.mit.edu/V110/N31/wings.31a.html

http://www.amazon.com/Fullness-Wings-Making-New-Daedalus/dp/083178265X

FWIW, at least one of the project members posts on these groups. And they did copy a few items from McCready's HPV (the first rule of engineering, btw, "copy shamelessly").

I think you should ask yourself what you want to achieve with your project. If it is just a little skip off the ground and a "landing", then I personally feel that you are putting a lot of work into what will amount to be very little long-term reward.

If you want to soar (this IS the thermal forum ya know), then you should ask, what type of lift is available? How strong is the lift? How windy is it typically? All these factors could strongly influence you design specification.

There are a lot of neat DIY glider projects from respected designers. I mentioned the Carbon Dragon - this design is very cutting edge and was recently written up in the Smithsonian. There is also the wooden Woodstock and Duster plans. All can be built in a garage and are very good fliers you could happily fly for hundreds of hours. Your design is a primary glider from the 30's with some new materials, ie it will become boring rather quickly.

Another thing for you to do is to buy some plans and study them. Most kit plans sold are for study only ("copy shamelessly").

My advice again is to build a reputable design before setting off to design your own, or as others have said, build a really big model of 6 meters or bigger.

/Adam

PS - I think fear of litigation is the reason most folks are not offering up ideas/comments publically on your design details.

regis

Mar 27, 2007, 01:31 PM

FF, you have impressed me with your knowledge and accomplishments. And I am a bit enviousness of your resources (shop equipment). Some have been pretty harsh in there judgment of you and in return you have tuned them out - typically (even if you are not a typical teen). I hate to see your enthusiasm quashed.
I hope you will at least listen to this bit of advice: Make a “proof of concept“ model first - maybe 1/3 scale. Fly it, test it, abuse it. Then think about it. No one on this site can judge weather you will ultimately succeed but we all know that no one has ever successfully produced an original safe plane on the first try. Regis

Jeffrito

Mar 27, 2007, 02:31 PM

copy shamelessly...

...There are a lot of neat DIY glider projects from respected designers... Woodstock and Duster plans. All can be built in a garage and are very good fliers you could happily fly for hundreds of hours. Your design is a primary glider from the 30's with some new materials, ie it will become boring rather quickly... buy some plans and study them. Most kit plans sold are for study only ("copy shamelessly").

My advice again is to build a reputable design before setting off to design your own, or as others have said, build a really big model of 6 meters or bigger.

That was some of the best advice I've seen, Adam, along with EAA membership. There is also the ESA, the Experimental Soaring Association (http://esoaring.com/) (formerly the Sailplane Homebuilders Association.) Reinventing the wheel may be fun for FF, but it's doomed to failure unless he acts on the good advice he's been given.

glderguy

Mar 27, 2007, 02:58 PM

Hi Steve, no Im not serious about the kid commiting suicide in his plane, but seems too me regardless of what is said, hes bent on ending up six feet under, so what are you going to do??? Hey kid, do you have parents? I am a firm believer in letting my kids creativity blossom, but once in a while there does come a time when I must step in and try to be a voice of reason. If that doesnt work then I unfortunately have to escalate measures a bit and somewhat limit the democratic process.
Walter

satinet

Mar 27, 2007, 05:06 PM

i think it's time to stop lecturing him now though - i think we've all put our 2 cents/pence worth in.

If he won't listen to people telling him not to do it, then at least your conscience is clear. just don't offer technical insight if you don't want liability.

So i am basically saying let him get on with it.........

Phil Barnes

Mar 27, 2007, 05:06 PM

For the benefit of those who didn't have time to read FF's previous thread or even all of this one:

His mother is a profesor at Stanford. He has mentioned his mother's boyfriend as well as his dad who helped in the destructive testing of his original wing panel (his dad lifted him and gently lowered him onto the center panel). So his parents have some knowledge of the project but FF has declined to answer my question asking if they knew he planned to get inside and fly the rather large "model".

FF has plans to provide an electric propulsion system for the aircraft consisting of some really cheap cells (nicads??) and a number of (model aircraft?) electric motors. And still talks about all up weights of 160 to 200 pounds and builds a spar based on that weight assumption.

FF talks about his definite plans to climb higher if the plane flies successfully at and below 10' of altitude. He feels safe because he plans to carry a parachute on his lap and throw it out if "the elevator linkage fails" (his words).

FF is attempting to build this entire project from the proceeds of his presumably part time job at the bike shop earning $10 an hour. This explains his desire to do the job on the cheap.

FF does not like to copy existing designs. He prefers to build his own stuff based on his personal intellect and intuition.

What I don't understand is why the moderators of this forum don't shut this sort of discussion down before RCgroups is sued out of existence when this kid's parents sue them for the wrongfull death/ negligent homicide (sorry I'm not a lawyer any more than I'm an engineer) of their son.

Jose E Bruzual

Mar 27, 2007, 05:10 PM

This thread sounds more like a cry for help or to get grounded for the rest of the school year, and if you are not promoting yourself as the first “meat servo” then I am not interested…

There are other communities out there best suited to assist in this endeavor …

http://home.att.net/~m--sandlin/bug.htm

http://www.airtalk.org/

http://home.ptd.net/~jlbaker/compact110.htm

• http://www.zhwin.ch/archaeopteryx/videos/Airborne.mpg

http://www.ruppert-composite.ch/english/531251969e07f2806/index.html

• http://www.ruppert-composite.ch/english/downloads/archstarts.wmv

Really, if you can’t do like those guys above, do you really want to be doing this? (rhetorical question, no need to answer)

satinet

Mar 27, 2007, 05:27 PM

so can we close this thread???

pleeeeeeeeeaseee

MTT

Mar 27, 2007, 06:45 PM

Unsubscribing...

flystoolow

Mar 27, 2007, 08:11 PM

FF do you have a sister?

Sisters make good test pilots ;) .

schrederman

Mar 27, 2007, 09:10 PM

I've reported this thread and made the same suggestions as Phil Barnes... for the same reasons. I have 3 kids.. now all grown and gone. This one scares me.

Jack Womack

jofo1

Mar 28, 2007, 02:11 PM

yeah but luke skywalker survived..........
...and lost a hand in the process.

rdwoebke

Mar 28, 2007, 02:45 PM

Brick*

I have not been following this thread as close as the first one.

FF, I hope every day that my daughter is half as interested in building planes as you are...

Ryan

satinet

Mar 28, 2007, 03:04 PM

...and lost a hand in the process.

but he could also hold and X-wing aloft using "the force". kind of..... not sure FF has that.....

If only you knew the POWER of carbon spars!

steve wenban

Mar 28, 2007, 04:20 PM

dropping out of this thread now also.
SteveW

artmonster

Mar 28, 2007, 07:39 PM

Why are you guys trying to close this thread?

I want to see FF finish this wing at least.

If he can pull off a 30' glider that flys...thats impressive...and I think he could do it, if he doesnt focus on the human factor.

The wing is cut and layed up pretty good so far considering.

And if he can keep the weight in the tens of pound...that thing will thermal like a banshee.....and big will be cool.....think how far up it will get before it specks out.... :D :rolleyes:

Lets encourage him to keep going on the thing, and build it into a huge gassbag.

I'd like to see a 30' RC glider built by him fly.....wouldnt you?

Lets work with him to get it flyable.

((hopefully we can hypnotize him to forget the human cargo aspect...... :p ))

FairlyFaded

Mar 28, 2007, 09:47 PM

Hey thanks artmonster, Well said, i wish there were more people like you...

Heres my plan, this may upset some people but im going to go with it.

I will not build a scale model of the plane because, I know i can build an rc plane that flys well, the first time. I have doen it many times before, also i dont think i would learn much from it because the techniques are the main part im worried about and they just dont really scale.

I WILL make a remote control version of myself. Basicly a set up that pulls the elevator stick and pushes the rudder petals. ill also put in how ever much balast would be = to me in it. This way the test will be exactly the same as if i were in it. I will then proceed to test the structure. Ill simulate the hardest of flight conditions and see what happens. I dont think anything bad will happen, but we will see. I also may put in some sort of a parchute system and test that too, all in good time...

Anyways, spring break is sneaking up (this weekend). And then the fun will begin.

I have been calculation how much my wing will end up weighing (using V of given mats etc. and there density) Looks like it should be around 15 lbs all up for the wing. Just trust me on that... cuse i didnt mess up the calcs. That is with the spar the glassed ribs the Trailing edge, the frontal D box (which i have a new idea for a skin) the carbon the balsa (which i will be testing) all the glue and the covering for the aft part of the wing.

Heres a pick of my new spar idea.... im going to do some tests on little versions of my spar. I have a feeling the foam will want to shear off of the spar cap even with the 45/45 glass, so im thinking of putting in a T to desperss the load into the spar itself.

From now on please no more posts telling me to stop,
I ONLY WANT ADVICE ON THE DESIGN! I relize alot of you wont be willing to give advice because you think im insane and incompatent and thus will die and you get sued, but please just trust me, if it isnt going to work i will relize it either while building or while flying it RC.

Anyways, this weekend should be interesting!

michael

p.s. thanks everyone who have been linking sites to me, they have been helpfull

Jose E Bruzual

Mar 28, 2007, 10:22 PM

Unsubscribe

Jeffrito

Mar 28, 2007, 10:43 PM

OK, RC is good. Just never attempt to fly in anything you make until it is checked out by a qualified person in the EAA, and without an FAA certificate of airworthiness.

Honestly, I don't know why you don't quit while you're ahead & try a proven kit, under EAA supervision, but at least this thread will be entertaining.

FairlyFaded

Mar 28, 2007, 11:26 PM

whats the point of saying unsubscribe? to make me feal bad? give me a break

JamieL

Mar 28, 2007, 11:30 PM

FF,

I was not implying that the planes you have built and posted in this thread did not fly well. But it seems to me that none of them are very complcated designs from a structural standpoint, at least compared to say a Supra or such. You are right, these things don't scale up accurately, so unless you have designed/built much larger models than the ones shown, you are taking a huge leap on this one.

I just thought it would be nice to suggest a way to test your principles and learn as much as possible on a smaller (smaller than 30ft that is) design which would be a quicker and much cheaper platform on which to learn. Sailplane wings are a great way to test your understanding of spar mechanics. A 4 meter wing with a root thickness of just about an inch requires an amazingly strong and efficient spar in order to survive a hard winch launch. Not much can be less than optimal with such demanding parameters. If you can get that right, then its safe to say that you can use the same principles, not design, to give yourself a better chance at getting this one right.

I'm just encouraging you to not discreded the value of building a smaller plane first. But if you are already set on building this right now, then good luck to you.

schrederman

Mar 28, 2007, 11:48 PM

What's the point of keeping this thread going where it doesn't belong... to make us feel bad? I don't want to know about it when you dismember yourself. Give me a break.

JW

FairlyFaded

Mar 29, 2007, 12:05 AM

schrenderman, tell me, how exactly am i going to dismember myself, or get injured for that mater? also does it really mater if theres one thread clogging up your forum?

Jamiel- Building a 4meter plane capable of "heavy winch" launches is completely different from what i am doing. I wouldnt use Very thin foam ribs bagged in glass on a scale as small as that, it just wouldnt make sence, i also wouldnt make even smaller foam ribs for the tail sections. This build will be much different then a 4 meter glider because i will be using foam instead of balsa.... The general design will be much the same exept for the lack of balsa... I didnt encounter any problems building things on the large scale with my first wing, infact its much easier, so im not to worried....

quietman

Mar 29, 2007, 01:00 AM

Here is something that may be of interest, and sorry if it has already been mentioned, I'm not going to read the whole thread:

http://www.soaravenal.com/gapa.htm

Avenal is not that far away, and the people at soaravenal are the best.

Surf their site and there are more pictures/flying impressions etc.

More:

http://jarek24.w.interia.pl/pw/pw2e.htm

I would imagine it worthwhile...

John Roe
www.roenation.com

Jeffrito

Mar 29, 2007, 01:08 AM

FF, why don't you just finish building something & prove us wrong that way? You sound like you have all the answers, but you won't have any proof of your deep aeronautical & engineering knowledge until you have a glider. Everyone has given up giving you design ideas already--it's up to you.

BTW, it is illegal to fly an aircraft (even an experimental one) until the FAA inspects it and (if it passes) gives you a certificate of airworthiness, so hurry up & build an oversized RC glider, and don't forget the pics. Stop wasting your time debating us & start building.

Jeff

flystoolow

Mar 29, 2007, 01:12 AM

I think it is time for some photos. Pictures are like soothers, and should curb the whining and complaining for a day or so.

I think you will have lots of fun with your project; great to hear you will test it as an RC glider first.

Can't honestly think of a better thing to impress any future employers than to show them photos of the huge plane you built as a teenager.

Take that last comment cautiously, as a bright mind is not to be wasted working for someone else....consider starting your own business one day.

Continue the good work on your plane, and by all means show us some photos please...you are about the only one creating something interesting, the rest of us are just sitting at our computers night after night nursing our lazy habits.

artmonster

Mar 29, 2007, 08:35 AM

Here is a thread by a guy who built a 34' RC plane, with some pictures.

http://www.rcgroups.com/forums/showthread.php?t=660655&highlight=birdman

I'd like to see this thing fly too. It looks like he built it real light, but it still came out to 168 lbs ( but that's with the engine I believe).

you can see in the pics how hefty his spar came out.....

interesting.

sekollera

Mar 29, 2007, 11:18 AM

snip...BTW, it is illegal to fly an aircraft (even an experimental one) until the FAA inspects it and (if it passes) gives you a certificate of airworthiness ...snip
Jeff

Not true, Jeff. For the sake of F-F, FAR part 103 says,

"§103.1 Applicability.
This part prescribes rules governing the operation of ultralight vehicles in the United States. For the purposes of this part, an ultralight vehicle is a vehicle that:
(a) is used or intended to be used for manned operation in the air by a single occupant;
(b) Is used or intended to be used for recreation or sport purposes only;
(c) Does not have any U.S. or foreign airworthiness certificate; and
(d) If unpowered, weighs less than 155 pounds; or
(e) If powered:
1. Weighs less than 254 pounds empty weight, excluding floats and safety devices which are intended for deployment in a potentially catastrophic situation;
2. Has a fuel capacity not exceeding 5 U5. gallons;
3. Is not capable of more than 55 knots calibrated airspeed at full power in level flight; and
4. Has a power-off stall speed which does not exceed 24 knots calibrated airspeed.

And onto certification,

"§103.7 Certification and registration.
(a) Notwithstanding any other section pertaining to certification of aircraft or their parts or equipment, ultralight vehicles and their component parts and equipment are not required to meet the airworthiness certification standards specified for aircraft or to have certificates of airworthiness.
(b) Notwithstanding any other section pertaining to airman certification operators of ultralight vehicles are not required to meet any aeronautical knowledge, age, or experience requirements to operate those vehicles or to have airman or medical certificates.
(c) Notwithstanding any other section pertaining to registration and marking of aircraft, ultralight vehicles are not required to be registered or to bear markings of any type."

In short, the FAA does not want to know they exist. No certification, no oversight by the FAA, no annuals, no training! Getting the picture?

I never "got" the Ultralight mindset. You have a very real chance of killing yourself in one. Ask yourself if your life worth the price of a proper aircraft, training, and a $150 annual?

You wouldn't catch me in one - well, a Sparrowhawk is a proper piece of kit, but even one of those ripped its wings off recently while flying over VNE...and no the BRS did not save the pilot because the entire craft blew up, ie, the cockpit severed from the rest of the fuse as the CF spar snapped forward. Guess where the BRS was located? He survived thanks to his chute.

http://www.ntsb.gov/ntsb/brief2.asp?ev_id=20061030X01573&ntsbno=DFW07LA006&akey=1

/Adam