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to buy or not to buy?


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Hi.

I am considering purchasing a cozy mk3 which has already been built. although some finishing is required,the airplane appears to be quite salvageable. There are a couple of problems. The plane was built and the owner died before flying it. The plane subsequently sat outside uncovered for a 8 years, and at one point, the cockpit had water in it which froze at some point. the filler has popped out in a couple of places along the turtle deck behind the cockpit and along the crease where it turns out into the wing. The left wing is off an aircraft that collided with a mountain and appears sound with no external damage, although I have no real way of telling. I have been advised by a couple of friends within the aviation community that the plane is not now nor ever will be airworthy. I am at a loss, and would appreciate some input as to whether to go ahead with the purchase. This is one of those "how long is a piece of string?" questions, but any input would be valued.

 

Thanking you

 

Chris

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Hi Chris,

I see that a few people have viewed your message, but none replied. I can understand why - it's impossible to judge without looking very closely at the airframe. Pictures wont do. I'd suggest that you get someone experienced in canard building to go with you and examine the structure very carefully. People who know "general aviation" wont do. You need an epoxy expert. Try the local EAA or look in the central states address list for a LongEZ or Cozy builder. If you really think the plane is a good deal and can't find someone locally, fly someone in to do an inspection.

 

The wing "came off a plane that hit a mountain"

Really? That doesnt sound very encouraging. You need to do a very carefully delamination test over the entire structure.

 

I hope this helps.

By the way - what is the price of this airplane?

I can be reached on the "other" forum http://canardaviationforum.dmt.net

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Hi John thanks for the reply

the guy i am buying it off paid $2000 cdn complete with a 500 hr 0-235 lycoming. I am looking to trade in my own homebuilt and with the money he gives me will end up owing me about $20,000 cdn. ($16,000 USD?)

Its a hell of a deal if the plane is sound.

Trouble is with the regs up here in Canada, the plane needs to be inspected, and with the word getting out about the history of the plane, it seems that none of the AME's locally will write the inspection. I may have a big problem here.

As far as that wing goes, one would think that any severe stresses would at least have partially translated into cracks or delamination at the wing mount bolt holes, but there is nothing, although its really hard to tell whats happening on the inside.

What I am also curious about is whether UV rays will affect a painted plane to the point of weakening the epoxy.The plane is painted yellow and is faded, but not that badly that a decent polish btings the shine back. Would UV penetrate the paint that much?

 

Chris

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>Would UV penetrate the paint that much?

 

No. Lots of EZs have sat on ramps for years with no problem. The things to watch out for are delamination, cracked surfaces and corrosion of aluminum parts such as the control linkages etc.

Yellow is unusual, but you can probably get away with it in Canada.

 

At $2000cn there's not much to loose... provided you DO get paid for you're plane. The engine is going to need an overhaul and the airframe is suspect. I still think the only way to be confidant would be to get a VERY careful inspection done by a canard / epoxy expert. Even then, as you say, there are things you can't see. I guess one way to check the structure would be to load up the wing and canard to, say 6 or 7 G and see if they show any signs of weakness.

 

By the way, one person to contact would be David Orr. He runs a canard finder service. David could probably advise you on the price and might be able to help you with someone to help with an inspection. David gets a small fee, but I understand that he's well worth it.

I can be reached on the "other" forum http://canardaviationforum.dmt.net

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why not just build a new set of wings??

 

Wings are fun i'v been building them for a long time, one day a week.

 

thats what i would do, look you have a huge head start on the project for almost no money.

 

the filler shouldn't have popped off, can you tell why it popped off, is the area shiney or was it filled with bondo, a very bad thing,

 

loading the canard and wing up would be a good idea, also check all flight control surfaces for balance.

 

Is the workmanship neat, what you can see of it?

 

do you know the tap method. tap the surface with a quarter and if the sound turns from a ring to a thud the layup or area is bad

 

 

Mike

maker wood dust and shavings - foam and fiberglass dust and one day a cozy will pop out, enjoying the build

 

i can be reached at

 

http://www.canardcommunity.com/

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Hi again guys

 

The place the resin popped off is quite shiny on the right side, but on the left (both places being where the turtle deck turns out into the wing) the fibreglass looks dry, as if there is no resin.What I suspect is water build up under the filler and when it froze, popped it out. The right side surface is definitely delaminated but looks very repairable. The resin on both sides at this crease is about half an inch thick! I'm an entry-level guy into composites but it doesnt look right even to me. I gave the wing a provisional tap test with the back end of a small screwdriver and didn't hear anything, but I will scrutinize them both with a quarter.

I have to tell you my initial joy at finding this plane is slowly disappearing as I close my eyes and imagine wing delamination at 160+. I live near Edmonton, Alberta, Canada, and although there are a few canard guys around,it seems that the spirit of fraternity that you share in the states doesn't reach up here. I will try a couple of emails that I have come across and try for some results.

 

Thanks again, and if you have any bright ideas, give me a buzz at cbflyboy@attcanada.ca.

 

thanks again

 

Chris

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I suggest that we check terminology.

 

When you say resin, do you mean pure epoxy? 1/2 inch of put epoxy would be an indication of radical builder error. Is the stuff brown, blue / green or clear? Is it just epoxy, or is there fiberglass there too?

 

It would be "fairly" normal, if not advisable, to have 1/2 inch of micro in the area where the turtleback joins the strake. This is the edge of the fuel tank, which should be 1 ply of uni and 2 ply of BID if I remember correctly. UNI is unidirectional fiberglass - the strands run in one direction only. Bid is Bidirectional and you will see the weave. If the top layer of fiberglass (either type) is dry / dull / weathered, then the stength is almost certainly compromised, and all the important bond between the glass and the foam is probably suspect.

 

You mention that one section is definately delaminated, but fixable. The way to fix delamination is to inject pure epoxy in the gap and clamp it down. Are you sure the foam is in good shape? It might be advisable to cut away a small section right down to bare foam and take a look.

 

"Taking a look" obviously implies that the "looker" know what to look FOR. Having said all this, almost anything fiberglass can be repaired, or rebuilt as Dust says for relatively minimal cost and not very much time. If the plane is built reasonably well and all you have to do is fix a few areas, or even build a couple of wings, you'd still have a huge head start compared to building from scratch ..... provided, of course that you can learn the skills needed. You could do this by helping another builder for a few days.

 

Hope this helps. Good luck.

I can be reached on the "other" forum http://canardaviationforum.dmt.net

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Chris,

A word of caution from a "non-builder owner". My airplanes did fly. They had problems, but the problems were mechanical and electrical, not structural. They varied from trivial to moderate. They drove me nuts, but I got them fixed. They took me a lot longer and were much more difficult for me to fix than would have been the case were I the builder. The key consideration is that I was qualified to address those types of problems going in. Then, I had a taxi accident that broke the canard mounting bulkhead (a major structural component). It would have taken the builder two or three weeks to replace that structural bulkhead and all of the fuselage forward of it. But I've had that busted airplane hanging over me for years. Reason is, I had neither the skills nor the confidence to do a major structural repair, and saw no viable way to acqire them. As I said, I do have skills in other important areas, but I can't do serious structural repairs yet.

 

The solution suggested to me is that I build the fuselage of my Cozy. Just like any builder, each step I do, each chapter I complete, I acquire the skills to do the next chapter, etc. By the time I get my Cozy fuselage done, I'll have the skills to fix my EZ (with the very important side benefit of getting the Cozy well underway). It will be a significant but not major project by then, but certainly not the insurmountable obstacle it is now. Most important, going through that process is IMO, the only way I can assure myself that I do the job RIGHT.

 

This is the type of thing you are getting into. I don't have any idea what skills you might already posess. I'm not recommending you quit or anything, just be aware that you're looking at a lot of stuff that a builder (any builder) is eminently capable of doing, but that will pose a MUCH greater challenge to you since you haven't done the preliminaries. You will have to consider very carefully where and how you are going to acquire the skills to PROPERLY do the repairs required (and, not incidentally, FIND and EVALUATE all of the discrepancies that need to be remediated). Both of my airplanes were flying. I ended up working long and hard straithtening out mechanical and electrical problems (which I am competent to do) and did OK until I ran up against a couple of structural problems which I was not qualified to work on. One, like I said, I will prepare for by doing the building process up to that point. The other, I got through with a lot of help from a friend.

 

As a general rule, I would recommend great caution to anyone buying an airplane. As for a project, the typical project for sale has maybe five or six months work actually done, but by not having done it himself, the buyer is woefully unprepared to finish the job. More better he just bite the bullet and do the few months himself and buy himself a LOT more assurance of eventual success with the whole project. On the strength of what I've learned about my unpreparedness to do major work, I strongly recommend against jumping into an advanced stage of a project. At the very least, I would highly recommend you pay as much attention to your own shortcomings as those of the airplane. Learn as much as you can about what you're getting into, particularly regarding your own part in the process and how you are going to get up to speed. Only then can you make an informed decision.

 

This probably sounds more intimidating and negative than it should, but you need to be very VERY careful. Of course, if you're getting this project for chump change, that's an important factor. My stuff cost me enough that I CAN'T afford to walk away if it turns out I bit off more than I can chew. An experienced builder could make a cottage industry of buying up projects cheap, finishing them off and selling the airplane. A beginner is probably much better off doing the whole project the "old fashioned way".

 

Y'all be careful out there now ... Jim S.

...Destiny's Plaything...

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I have six pictures to show you all. Cant seem to be able to attach them to the reply. A few pointer for sending multiple pics would be appreciated.

Thanks, by the way, for all your help and support.

 

 

Chris

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You can attach them by inserting a link to the pictures (which I have never done) or inserting them using the "Attach file" option at the bottom of the reply box. Make sure the file is not too large. You can make them smaller using Photoshop or similar programs. I think you can attach one per reply.

 

If you send to my work (mlafleur@visteon.com) I can attach them for you.

Mike LaFLeur - Cozy MkIV #1155
N68ML
76225.gif

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jim, very well written.

 

As i have said, the plans are a degree in building. From flat and simple to curved and complex, when you get to a chapter, you HAVE the ability and experience to handle the job.

 

Enjoy the build

 

Mike

maker wood dust and shavings - foam and fiberglass dust and one day a cozy will pop out, enjoying the build

 

i can be reached at

 

http://www.canardcommunity.com/

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you can load the plane to test it.

 

glass, unlike metals, wont fatigue. You can stack up 9G's on the wings and spar. If it fails you will know. If not you will know.

 

"Composite Basics" by Andrew Marshall has a description of what and how to do such a test.

 

I can't understand how filler would pop off due to water and freezing. Shouldn't any filler to epoxy connection be water tight?

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Originally posted by LargePrime

you can load the plane to test it.

This is certainly true, but a LOT of work.

 

glass, unlike metals, wont fatigue. You can stack up 9G's on the wings and spar. If it fails you will know. If not you will know.

I don't know where you got the idea that composite materials do not fatigue. See:

 

http://www.coe.montana.edu/composites/

 

Click on "publications", and then #14 for a clear indication of fatigue issues in multiply fiberglass layups. Pay particular attention to page 8.

 

On the other hand, what fatigue has to do with a single static test of wing/spar strength, I certainly can't see. If there's a low cycle fatigue issue with ANY parts in the plane, then there's a design problem, not a fabrication problem.

 

"Composite Basics" by Andrew Marshall has a description of what and how to do such a test.

Maybe, but as Burt Rutan showed when static testing the canard, proper mounting and loading is paramount. This is not a trivial pursuit.

 

I can't understand how filler would pop off due to water and freezing. Shouldn't any filler to epoxy connection be water tight?

Lots of things SHOULD be the case. Poor surface prep. can easily lead to filler loss, as could filler thicknesses that are too high. Wrong epoxy, crappy sanding, etc.

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as a general rule, shiney surfaces under filler is bad. epoxy/epoxy and micro or flox adhere by a mechanical bond/ not a chemical bond. the shiney surface would suggest poor surface preparation prior to filling. We always sand to get rid of the shineys before filling.

 

enjoy the build

 

Mike

maker wood dust and shavings - foam and fiberglass dust and one day a cozy will pop out, enjoying the build

 

i can be reached at

 

http://www.canardcommunity.com/

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another stupid note on terms.

 

resin = resin

 

hardener = hardener

 

resin + hardener = epoxy

 

epoxy + micro = non structural light filler

 

epoxy + flox(cotton micro fibers) = strong structural heavy filler

 

epoxy + chopped fiberglass = (i hear) stronger structural filler (not called for in plans)

 

epoxy + sawdust = good blemish filler for furniture, oh sorry off topic, please forum police don't chastize me

 

The colors vary based on the epoxy system that was used, but the appearance of micro and flox should be easy to determine.

 

cmon down to detroit and work for a day, at the end of it you will understand much more than you do now.

 

We ofer all slaves, i mean helpers, free room and board and we make you do the work, not just watch.

 

 

enjoy the build

 

Mike

maker wood dust and shavings - foam and fiberglass dust and one day a cozy will pop out, enjoying the build

 

i can be reached at

 

http://www.canardcommunity.com/

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It seems that the common thread here is that the filler popped out due to poor surface prep. I have been able to slide a small plastic scraper under all the loose stuff and taken the filler back as far as it will go. It's fairly easy to see where the filler has not adhered and I have removed it as best as possible. Just how far should I go back with the adjoining surface, or should I stop when I cant get the blade under the filler without significant effort?

 

I have to tell you that although I am new to composites, the thought of lifting the plane by the wings and puttingg force in the centre is quite honestly terrifying and more that a little suspect as a recognised way of testing fatigue. I can't help wondering if the very act of putting the stress on the wings is enough to fatigue those that were previously solid!

 

I have done the "tap test" and they sound good.The only variance in sound I could hear is along the full length of the wing at the point that I must presume is the spar.At this point the sound turns to quite a high ring in comparison to the rest.Does this sound about right?

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Well ifin you are afraid to lift the plane by the wings and put weight on it, you better not fly it, he he he.

 

I don't know the exact way to weigh the plane down for testing,

 

It wouldn't be as hard as it was for burt rutan as he was testing to falure and went to 14 g's before the holding structure failed.

 

 

Did you buy the plane?

 

I take it that the area under the bad filler was shiney.

 

is the filler micro or bondo or something else?

 

do the plans come with the plane? that way you can learn about what you should do and the recommended ways to repair items, it is in the plans

 

sanding/grinding off filler and reglassing is not a big deal, the wings have just 2 layers on the bottom and three on the top

 

the fus has, i forget at least two and in some places 3, the plans detail it all.

 

How is the overall workmanship??

maker wood dust and shavings - foam and fiberglass dust and one day a cozy will pop out, enjoying the build

 

i can be reached at

 

http://www.canardcommunity.com/

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>should I stop when I cant get the blade under the filler without significant effort?

Yep. I would.

 

>the thought of lifting the plane by the wings and puttingg force in

>the centre is quite honestly terrifying and more that a little

>suspect as a recognised way of testing fatigue.

I understand you're concern. My thought was that a few g would test structural integrity, not fatigue. If somethings going to go "crack" and fall off, you'd want to know this before flying so stressing things a bit on the ground might be a good plan.

 

It would be a good idea to get some advise from a REAL expert on this issue. While they'll all probably say its impossible to tell without closeup personal inspection, you could try an email to the man himself, Burt, or Mike Melville. Possibly Nat Puffer could give you some input, or Jeff Russell. Another name to try might be Dennis Oelsen. All of these people have built, and in some cases designed, multiple canard airplanes. By contrast, most of the opinions you'll get here are from one-time builders.

 

It sounds like you bought it already. If so, good luck with the repairs. Yes. The tap would sound different over the spar cap. You should get the same on the canard until about 6 inches from the end where the spar cap ends.

I can be reached on the "other" forum http://canardaviationforum.dmt.net

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just a thought here, these planes are engineered STRONG. I have seen longs at oshkosh that looked like hell with very poor workmanship and obviously had allot of air time

 

I mean with the quantity of planes flying how many structural falures have there been???

 

The canard is good to more than 14 g's, ok so a really poorly constructed one is only good to 8???

 

Didn't the canard with many holes poked in it also go to 14 g's

 

You will have to go over the plane in great detail tapping and looking, but repairs are within your ability

 

Doing a weight test might not be a bad idea, but you don't have to go to 14 g's, what is the wing loading per square foot?

 

triple it, lots of returnable bags of concrete, he he he

maker wood dust and shavings - foam and fiberglass dust and one day a cozy will pop out, enjoying the build

 

i can be reached at

 

http://www.canardcommunity.com/

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Dust said:

sanding/grinding off filler and reglassing is not a big deal, the wings have just 2 layers on the bottom and three on the top

 

Scraping is a good plan. If you do grind, be careful not to grind into the glass. As dust says, there are only 2 or 3 plys in many areas. Grind through the fibers in one ply and you could be halving the strength.

I can be reached on the "other" forum http://canardaviationforum.dmt.net

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reglassing is not hard, in case there is more than bad filler, like unpainted fiberglass that has been exposed to the sun, or bad areas of glass both on the wings and every where else, don't just focus on the wings, focus on everything.

maker wood dust and shavings - foam and fiberglass dust and one day a cozy will pop out, enjoying the build

 

i can be reached at

 

http://www.canardcommunity.com/

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Thanks for the replies and advice, and DUST I'm not scared of flying it, just making a fibreglass lined crater hehehe

 

The workmanship seems to be overall very good.The glassing and filler are very smooth and even.The guy had previously built a longEZ and I would say quite competent. Where the plane lacks is in detailing. I suspect that at the end, he was not well, as he died not long after taxi tests, and the bird never flew. He left pit marks in the glass and some of the filler edges are a little rough.It's almost like he wanted it finished and just threw the paint on.Although I am new at composites, I do have building and repair experience, and I would estimate that there is less than 200 hrs left to completion, which includes reconfiguring the hotch-potch instrument panel and at least a patial teardown of the 0-235.

 

I do have some advice however, as a newbie to even you experienced guys.

The LongEZ that this fellow built was sold in British Columbia.It subsequently crashed, killing the pilot.I have talked extensively to the TSB about the crash and it turns out that the builder used explosafe in the fuel tanks. This material apparently holds water like a sponge, and under vibration rains it out. The engine on the crash plain suffered a chronic loss of power at low altitude, and during a steep emergency turn (60degree left wing down, 24deg nose down) trying to both line up for a field landing and trying to crank down the gear, the engine cleared and powered him into the ground.Water in the carb was the culprit. Investigation found that 5% of the total explosafe used in the tanks was able to hold 175ml of water,and that was the major factor in the crash. The fact that the guy had 100hrs logged total, 2.4 check flight on type and hadn't flown for 5 years were all contributing factors, to say the least.So if you are thinking of using explosafe,then do some research

 

Blue skies

 

Chris

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