Newbie Questions - Considering Building

[Drech]

Hey all,

 

I'm interested in learning to fly and thought it would be fun to concurrently build a Cozy. As my brother is a flight instructor, I asked him to see if any of the people around his flight school had experience with these types of planes (Vari, Long, Cozy, etc.) and some of the answers were strange.

 

One person in particular said he would never build another Long because the UVs in the sunlight caused the foam inside the wing to shrink and that, while repairs were possible, he might as well just throw the plane away. That seems rather extreme.

 

Now, I've never read anything to that effect anywhere on the net but wanted to verify with you all as I know zip about any of this as yet. Maybe he is referring to something indirectly and I don't understand.

 

The other question I have is regarding the Cozy cabin. One thing I never liked about the small planes I've flown in is how crowded it feels when side-by-side. How do you know what kind of modifications are reasonable without adversely affecting the way the plane flies? How do you figure out the limits of what you can do, for example widening the cabin for more room?

 

I appreciate any responses and look forward to interacting here soon, hopefully on a more relevant level

 

~D

[adouglas]

Not a builder myself (at least not yet), but here's what I do know:

 

1) If the airplane was properly painted in the first place, UV would never make it to the glass, much less the foam.

 

2) The foam in the wings (blue foam) is eaten by solvents, including gasoline.

 

Given these two facts, it sounds more like the guy has a fuel tank leak.

 

ANYTHING is repairable, AFAIK.

[Jon Matcho]

Welcome!

 

One person in particular said he would never build another Long because the UVs in the sunlight caused the foam inside the wing to shrink and that, while repairs were possible, he might as well just throw the plane away. That seems rather extreme.

Yes it does, and the only other thing I can think of is if that plane was painted a dark color, or had a dark stripe. That could cause the fiberglass skin to heat beyond the safe temperatures for the foam and/or epoxy (around ~150F), causing air pockets, delamination, and possibly what that guy described.

 

Still, that's not to blame composite construction -- there are many other plane types out there that use foam and fiberglass. Here's a color chart that shows you should only paint your foam-fiberglass plane white and maybe some yellow (breakdown temps @ 140-150F): http://www.maddyhome.com/cozy/chapter?c=25&s=5

[Drech]

Thank you both for your replies. I wondered why most planes were white, now I know.

[Nathan Gifford]

...One person in particular said he would never build another Long because the UVs in the sunlight caused the foam inside the wing to shrink and that, while repairs were possible, he might as well just throw the plane away. That seems rather extreme...

It shows how little he knows. I don't know how many of these foam planes are flying but the Varieze 30th Anniversary is coming up. There will be a number of high time birds at this celebration.

 

If it were true, you'd be able to read the NTSB reports about about structural failure of composite a/c. The failures that have happened have everything to do with poor construction or bad flying and no UV radiation. Heck plenty have been left out in the sun in Arizona and New Mexico.

...The other question I have is regarding the Cozy cabin. One thing I never liked about the small planes I've flown in is how crowded it feels when side-by-side. How do you know what kind of modifications are reasonable without adversely affecting the way the plane flies? How do you figure out the limits of what you can do, for example widening the cabin for more room?...

There are other homebuilts that have more room: Aerocanard (Cozy Clone) and Velocity XL. None, I think have the comfort of nice Camry, but neither can a Camry do 180 knots for 1,000 miles!

 

The big advantage of the Cozy and Aerocanard are the construction costs and the fact that you can build everything directly from the plans. The $500 plans set gives all the information you need to build one. These planes can be and have been built for around $45K.

 

The Velocity XL, is also a very nice plane but it will cost considerably more depending on how it is equipped and which fast build kits you purchase. Another advantage of the Velocity is that the parent corporation is still doing development work. I haven't seen much done with the Cozy beyond what Aerocad did with the Aerocanard.

 

What a few people have told me is that they believe most four-seaters fly with only two people aboard. That leaves a humongous space for baggage. I was hoping I could dig up the link on someone's Cozy trip to Florida, but I can't find it. The final photo of that trip shows all the gear they stowed in the back seats.

[Drech]

Great points!

 

I have one more question that was brought up by one of the locals asked. They are under the impression that an aluminum plane is much stronger and therefore more resistant to hail damage or debris damage caused by high winds than a composite aircraft would be.

 

I may be wrong but I thought the reason composites were such a revolution is because they are just as strong but lighter than traditional materials.

 

Your point about some of the composite planes being left outside (albeit in nice-weather locations) seems to point to the opposite.

 

Just how strong/resilient is a composite plane compared to an aluminum one?

 

Thanks for the help and info given: it's nice to put some of this stuff to rest.

 

~D

[Norm M]

I have one more question that was brought up by one of the locals asked. They are under the impression that an aluminum plane is much stronger and therefore more resistant to hail damage or debris damage caused by high winds than a composite aircraft would be.

Have you seen what an aluminum plane looks like after it has been hit by a hail storm? The aluminum will dent, and not much can be done short of reskinning it, or flying it with dents.

 

Your point about some of the composite planes being left outside (albeit in nice-weather locations) seems to point to the opposite.

Ask Georger Graham how composite planes hold up to Buffalo, NY winters. I don't know which is rougher, sitting in the ice & snow, or sitting in the heat.

 

Either way, if you are leaving your plane outside in hail storms and ice storms, you can expect that it will weather a bit over the years. Some people use covers, but remember that covers can scuff the canopy also.

 

-Norm

going from sharing a hanger to having it to myself in a week!

[Nathan Gifford]

...I have one more question that was brought up by one of the locals asked. They are under the impression that an aluminum plane is much stronger and therefore more resistant to hail damage or debris damage caused by high winds than a composite aircraft would be...

Have them show you an aluminum plane with hail damage. Have they beat out all the little dings that stones have left? I know the local FBO got a great deal on Piper Cherokee they bought because it had a little hail damage (and still does).

 

Try reading Sucker Hole by Al Hodges about hail damage on a composite structure in flight. Its only one incident, and not every flight may have such an outcome. Its hard to judge whether it is easier to repair an aluminum structure or composite one.

 

The problem about hail damage while on the ground, is what weather is likely to bearing down on tarmac. Those pesky high winds and little tornados like converting a/c into lawn darts. I guess that is what insurance is for?

 

Do realize that canard forums are going to be prejudice towards composite structure, construction techniques, and canards. There are a pot full of RVs out there and they seem to make up the bulk of new experimental a/c (means they are obviously doing something right).

 

That said, you are going to find it difficult indeed to build an RV for what a Cozy (or Aerocanard) costs. The tools for composite structures are fewer than they are for aluminum (save big bucks on tools), but some people would rather shoot rivets rather sand, sand, sand fiberglass a/c.

 

The BIG THING TO REMEMBER is that 80 PERCENT of the projects started are never completed, aluminum or composite. This is where the Cozy shines since you only need buy the materials for the sections you are working on. If you tire and abandon your project along the way you are going to get cents on the dollar for your material. That means the new buyer gets the good deal if you quit (and Ebay!).

 

Right now, you are doing the right thing: asking questions! Remember, like Dust says, "Enjoy the build", because that is what you will be doing for 2 to 10 years.

 

I talked to the Cozy designer, Nat Puffer. He says you can build a Cozy in 2.5 years if:

 

• Stick to the plans.
• You do something everyday on the a/c (Mike Meville says if you are curing something everyday).
• Stick to the plans.

Nat said he still took a week off each year with the family and did other fun things, but the rest of his vacation, mornings, nights, Saturdays were spent building the plane.

[Nathan Gifford]

...What a few people have told me is that they believe most four-seaters fly with only two people aboard. That leaves a humongous space for baggage. I was hoping I could dig up the link on someone's Cozy trip to Florida, but I can't find it. The final photo of that trip shows all the gear they stowed in the back seats...

Well I finally found it at http://www.cozybuilders.org/flying_reports/2003_04_07_S&F_trip.html

[Spodman]

Back to the subject of UV, Burt Rutan apparantly setup a very early reject (and unfinished) canard off a Vari as an outdoor table for YEARS, without any real deterioration. The only problems experienced in deterioration is when solvents/fuel dissolve foam they shouldn't be in contact with, and in the alloy bits!

 

I have seen some rivetted rhapsodies, and some other alloy machines I wouldn't keep chickens in. Modern CNC kits you just cleco and rivet have drastically cut the build time and seem quite idiot proof. Sadly though, the idiots keep getting smarter...

 

The cost is not enormously different, I'm building a Cozy because I want 4 seats and the RV10 looks boring.

[adouglas]

If you're worried about impact damage, get a copy of the "building rutan composites" video (available from Aircraft Spruce, and worth the money) and watch Burt jumping up and down on a wing section. An aluminum wing section of the same weight failed catastrophically under the same treatment (it was Mike Melvill jumping on the aluminum piece, but he's smaller than Burt).

 

I'm not an engineer, but I'm feeling in a Holiday Inn Express kind of mood this morning, so....

 

A point load on a composite skin can punch a hole or (more likely) cause a delamination, but consider that the composite structure is a true monococque...ALL of the skin carries load. So the loss of strength is minimal, no matter where the damage occurs. An aluminum structure is a semi-monococque...the skins between the ribs, spars, longerons, bulkheads, stringers, etc. do not carry most of the load...the underlying structure does (the skin does carry some load, hence "semi" monococque). The loads are transferred via the rivets. So an aluminum structure has a myriad of tiny stress concentrations around the rivets. Punch a hole in an aluminum airplane where there are no rivets, and you don't lose a whole lot of strength...but damage it where the rivets are, and you lose a LOT of strength.

[Drech]

I'm starting to feel more at ease. These veteran flyers were beginning to make it seem like anyone who flies a homebuilt canard is risking their lives on a construction that's sure to fail.

 

While I realize it's only as good as the person who built it, and if you do a bad job it won't be safe, I can't imagine anyone letting something slide when in fact it is your own neck on the line.

 

I'll grab the Rutan video mentioned and check it out.

 

Thanks again for the responses! They are much appreciated.

 

~D

[Waiter]

Drech,

 

My LongEZ has a little over 2600 hours on it. A good portion of that is high altitude (FL180) and long distance (> 2000 miles).

 

But I do have one story I'd like to share regarding the strength of this airplane.

 

TESTIMONY TO COMPOSITE CONSTRUCTION

 

In all my years of flying, and the many different types I've flown, I once had an encounter while in my LongEZ , that I know, if I had been in a Cherokee, or a Mooney, I wouldn't be writing this today.

 

I departed San Jose's Reid Hillview airport and headed northwest along Mission Peak at about 2500 ft. The RHV ATIS that afternoon was reporting light to moderate turbulence.

 

All the sudden, I remember feeling a very hard bang, like a car just ran into the side of my plane, I was thrown hard against the side of the plane.

 

Have you ever seen those "Cop Chase" video's on TV when the bad guy runs a red light at 70 mph and slams into the side of an innocent car, Thats what this felt like. I wasn't spinning, but I could see and fell the plane rolling.

 

I hit my head on the side of the canopy so hard, I kind of squinted my eyes closed as I knew the canopy was going to explode. I don't think I passed out, but I realized I was almost inverted and I could see a lot of sky. My brain was operating in the "slow motion mode". For a very brief second (probably only 1/10 of a second) I thought I had a mid air collision and the airframe was breaking up. Instinctively I moved the stick in the opposite direction of the roll and at the same time turned my head to look outside where I fully expecting to see debris, where the wings were supposed to be. I was actually surprised, and confused to see my wings and rudders. The roll stopped but with a very nose high attitude, I recovered gently to straight and level and found that I was almost at 4500 ft.

 

It was obvious from my very brief visual inspection that it wasn't a mid air, all the pieces still seemed to be attached. I couuld move the stick and rudders, and everything seemed like it was working, so it probably wasn't a control failure. I called RHV, and declared an emergency. I told them I just had a severe upset and lose of control, I currently had control of the plane and I would be doing a slow southernly turn through San Francisco's air space, and vectoring myself for a straight in to RHVs runway 13. I squawked the 7700, and probably pissed off a couple 747s on final to SFO, but to bad.

 

After days of thinking and talking to others, I came to the conclusion that what I encountered was most likely a horizontal rotary, coming off the WEST side of Mission peak. I think the plane may have rolled twice, The first roll was the bang and sideways motion I felt, and the second was the one I think I was seeing. I also gained about 1200 ft during this encounter. The big goose bump on my head was check out, and determined to be a minor concussion.

 

I firmly believe, had this been a production aircraft, it would have snapped the wings off, the initial thrust was that violent. This unexpected encounter is a testament to the design and construction of this aircraft.

 

Waiter

[Marc Zeitlin]

I'm starting to feel more at ease. These veteran flyers were beginning to make it seem like anyone who flies a homebuilt canard is risking their lives on a construction that's sure to fail.

There are close to 2000 Rutan derivative canard aircraft flying (V.E., L.E., COZY). There has NEVER - let me emphasize this - NEVER been a structural failure of ANY properly built aircraft of these three types. NEVER. In around 2000 instances. Not one documented case. Any time there has been a structural failure (and there have only been a very few), it has been traced to a SEVERE issue with the builder's work.

 

RV's are wonderful aircraft. Cessna's and Pipers are wonderful aircraft. However, those three companies can NOT make the same claim. There HAVE been structural failures of properly build instances of these aircraft.

 

Your acquaintances are severly misinformed and/or deluded.

[Drech]

@ Waiter:

 

Wow, that's quite a story and a testament to the design and construction of the plane, and you.

 

@ Marc:

 

Those numbers are very reassuring. What those guys have said just doesn't seem right. I get the feeling some of them like to talk just to hear their own 'expert' view on the matter Not trying to trivialize their experiences, just that they don't match the consensus here, a far greater sampling of experienced pilots and builders.

 

@ all:

 

First, I'm not handy. I ordered the composite practice kit to get an idea of the process and will do that when it arrives. I hope it's a decent intro to the skill. The Rutan video should help as well.

 

I hope I can actually do this and learn the skills to complete it given my rather 'indoor' nature (I'm a computer geek by trade AND at heart).

 

I had my first flying lesson on Saturday and I feel on fire now to get the cert and build.

 

I'd ask about deciding between the Cozy and the AeroCanard but I see there's already a thread for that. It seems like a sensitive subject but as a consumer I need to know: what happens to Cozy licenses if the Aero agreement is upheld in the end? What about the other way around? I'm interested in either the Cozy or the Aero but since it's those two going at it, not sure what it will mean either way.

 

I've also read the Aero hasn't been updated since it first became available but I don't understand what that really means for building. Is the Cozy safer with it's updates or does the Aero still stack up in it's present form?

 

Anyway, thanks again for all the responses =) You guys are making me feel good about this whole thing!

[Waiter]

Like Marc said, I don't know of any canard that came down due to structural failure. Thats in itself is a testament to the design.

 

If I was going to do this again,, I'd also keep my eye open for a project that someone had started, but they ran out of steam. You can usually get these for the price of the parts. If the workmanship is up to standard, this is a good way to kick start a project.

 

ALSO, Take a look at the AeroCanard plans. I have the Shareware version on my web site.

 

www.iflyez.com

 

These will give you a preview of what the to expect. Most of the canards will use vary similar techniques and procedures.

 

If you decide on an AeroCanard, please visit their web site, and purchase the full set. The full set comes complete with full size templates, drawings, and builder support.

 

Waiter

[Drech]

Thanks, Waiter, and all =)

[Nathan Gifford]

...I'd ask about deciding between the Cozy and the AeroCanard but I see there's already a thread for that. It seems like a sensitive subject but as a consumer I need to know: what happens to Cozy licenses if the Aero agreement is upheld in the end? What about the other way around? I'm interested in either the Cozy or the Aero but since it's those two going at it, not sure what it will mean either way.

 

I've also read the Aero hasn't been updated since it first became available but I don't understand what that really means for building. Is the Cozy safer with it's updates or does the Aero still stack up in it's present form?...

With the legal system who knows what the final outcome might be. If I understand the legal battles, the arguments are whether Aerocad can sell plans sans quick builds and can/was Cozy withdrawal from the agreement OK. Realistically, I would not worry one way or the other about it because both ships are really plans built which means win, lose, or draw you have all the information necessary to complete building process. Besides that, Aircraft Spruce now owns the Cozy plans and that may change everything.

 

Some people have bought both sets of plans, using some of the fuselage templates to build a wider Cozy. This was less financially draining when you could pickup the Aerocanard plans for $250.

 

The Cozy and Aerocanard are pretty much the same machine. Someone else will need to chime in on how critical this issue is, but I think the really important updates for the Aerocanard are the same ones that apply to Cozys.

[Jon Matcho]

Some people have bought both sets of plans, using some of the fuselage templates to build a wider Cozy. This was less financially draining when you could pickup the Aerocanard plans for $250.

 

The Cozy and Aerocanard are pretty much the same machine. Someone else will need to chime in on how critical this issue is, but I think the really important updates for the Aerocanard are the same ones that apply to Cozys.

Understand that we're talking about the plans-built AeroCanard here and not the kit-built AeroCanard (for which parts still work as options of the plans-built).

 

If I was aiming to build an AeroCanard FG-sized aircraft, which I am, at this point in time I would highly recommend:

• Purchase the Cozy Mark IV 3rd edition plans from Aircraft Spruce so you have all the fixes and corrections.
• Purchase the AeroCanard FG plans-built plans so you have the rear seat widening modification.
• Build using the Cozy Mark IV plans, but before starting each chapter, identify what mark-ups exist in the AeroCanard FG plans and adjust your measurements accordingly.

That sounds like a lot of work, but the plans nearly identical and I have found this process to be rather easy. There's only really a few places where there are differences.

 

As far as costs go, I was able to get AeroCanard FG plans for a substantial discount way back because I mentioned I already had Cozy Mark IV plans. Also, for ANY modification, what's it worth to you? I gladly sent Uli Wolter $50 for his forward-opening canopy plans and would purchase add-on designs from others if I wanted them.

 

Finally, I expect this scenario to evolve in the years to come. With new ownership at AeroCad, it's quite possible that the AeroCanard will evolve at a much more rapid pace than the Cozy Mark IV.

 

As far as legal wranglings go, anyone who has plans for either plans-built aircraft has no worry. I also don't see Aircraft Spruce or AeroCad wanting to spend any time and money in court. I'm optimistic they'll look to work things out between themselves.

[Nathan Gifford]

...If I was aiming to build an AeroCanard FG-sized aircraft, which I am, at this point in time I would highly recommend:

• Purchase the Cozy Mark IV 3rd edition plans from Aircraft Spruce so you have all the fixes and corrections.
• Purchase the AeroCanard FG plans-built plans so you have the rear seat widening modification.
• Build using the Cozy Mark IV plans, but before starting each chapter, identify what mark-ups exist in the AeroCanard FG plans and adjust your measurements accordingly.

That sounds like a lot of work, but the plans nearly identical and I have found this process to be rather easy. There's only really a few places where there are differences...

I have heard that said before but avoided repeating them because of the litigious atmosphere.

 

...As far as legal wranglings go, anyone who has plans for either plans-built aircraft has no worry. I also don't see Aircraft Spruce or AeroCad wanting to spend any time and money in court...

I hope the problems can be resolved too. That fight has gone far too long.

[bferrell]

Not to say that they aren't safe, because I'm building one, but there have been a couple of failures in flight.

 

Velocity - http://www.ntsb.gov/ntsb/brief.asp?ev_id=20040825X01289&key=1

 

This one didn't come down, but sounds like a very close call:

VariEze - http://www.rutanaircraft.com/htmlpages/canard.html

 

Brett

 

Like Marc said, I don't know of any canard that came down due to structural failure. Thats in itself is a testament to the design.

 

 

www.iflyez.com

 

Waiter

[Waiter]

Good read.

 

The first one is still ongoing, but looks like a typical continued vfr into ifr conditions. I didn't see any mention of local thunderstorms!

 

I was involved in the investigation of an accident similiar to this. The aircraft encountered ice, and found itself on its back in a similiar deep stall mode. The aircraft came down in an inverted flat spin from approximately 18000 ft, and hit the water intact. The water impact destroyed the aircraft and killed the pilot.

 

The second one is the infamous wing attach point corrosion. Some of the aluminum attach box on the VariEZ had corrosion problems.

 

Waiter

[adouglas]

That NTSB report is a preliminary, not a factual report or statement of probable cause.

 

Be that as it may, the witness said the airplane came out of clouds in an inverted flat spin and THEN the wing came off.

 

ANY airplane will shed a wing if you overstress it beyond the design limits.

 

The ceilings were at 900 feet. If he emerged from the clouds at 900 in an inverted flat spin, there's no way he was going to recover anyway (assuming he could). That airplane did not crash because of airframe failure (assuming there was not an additional failure that isn't in the preliminary report and assuming the witness account is accurate).

[Nathan Gifford]

There is certainly enough information to believe that weather played a large role in the loss of this aircraft and occupants. It is doubtful, that some kind of control failure leading to the crash will ever be determined one way or the other. That is one of the problems with experimentals, the aircraft will probably always be more suspect than their certified cousins.

[bferrell]

This gentleman's son posted to the Velocity group that he believed the cause was VFR into IMC, and that this was something that his father regularly did. It seems fairly certain that disorientation and loss of control were the primary failure mode, and that if the structure failed, it was secondary and not unreasonable given the aircrafts speed and attitude.