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Canard Question


wzenheimer

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Hello all,

 

New to the forum, but long time ghosting reader. I've recently purchased a Long Ez project that is near completion. Matter of fact I haven't even seen it up close yet. I found the project (900 mi away) and located an EAA tech advisor that offered go look at it for me. He took 35 pictures and then spent 2 plus hours on the phone describing the details and workmanship. He went on to write a formal EAA tech inspection and sent it to me in case I purchased the project. From that conversation, I was assured the project had excellent workmanship, plans intact, templates laid out on varnished wood etc. The project was at such a great price I didn't want to let it get away so I went ahead and put a deposit on it. Which leads to the only question neither the tech counselor or the owner (2nd owner from original builder) couldn't answer.

 

Neither could answer if the project had a completed Roncz Canard or an original GU canard. Included in the pic below is the canard template used to make the canard. I was hoping that someone on here could tell just by looking if it is a Roncz Airfoil or a GU. Any help would be appreciated and thanks in advance.

 

Regards,

Chris

post-27162-141090167105_thumb.jpg

Christopher Wise

Lake Saint Louis, MO

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That is what I thought...thanks for the reply. Looks like I'll be building a canard...:cool2:

 

Chris

why? there is nothing wrong with a GU canard. some have a slight pitch change in rain, most do not have enough to be of a concern. all but a few long ez's fly with a GU. any time someone has showed me a Gu that had a big pitch change in rain it was a very badly finished canard. Burt told people not to use to much filler on the plane so as not had weight. but some took it to far and did not even fill enough to make the contour correct and if you do that on a GU canard you will have trouble. contour them correctly and they fly fine.

Evolultion Eze RG -a two place side by side-200 Knots on 200 HP. A&P / pilot for over 30 years

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My longeze has a Gu canard and it flys great. Does have a pitch trim change in the rain. The Gu canard is a lot easier to make than the ronze canard. I would only make another one if you planned on flying in the rain or lived where it rains all the time. STeve build on

Steve Harmon

Lovin Life in Idaho

Cozy IV Plans #1466 N232CZ

http://websites.expercraft.com/bigsteve/

Working on Chapter 19,21

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I would build a Roncz. It doesn't take much time to build a canard.

 

I took off in my GU-canard Cozy III once from Williamsburg-Jamestown airport on a very foggy, moist day--almost 100% humidity for sure. The airplane took every foot of the 3200 foot runway to rotate and would barely climb. Scared the **** out of me. There was enough moisture in the air to screw up the GU airfoil. 'Course the EZ doesn't have the frontseat load of a Cozy to complicate the problem but why mess around with old technology and retrimming.

-Kent
Cozy IV N13AM-750 hrs, Long-EZ-85 hrs and sold

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Whatever canard you build, the key is build it accurately. Performance is 100% predicated on that advice.

 

I don't believe the Roncz is harder to build. I found the layup internal to the centresection spar more difficult than anything on the Roncz. The Roncz was the best part I made.

 

The GU is lower drag than the Roncz.

 

Having seen the report online, I would definitley build a Savier airfoil canard (modified roncz with slightly longer leading edge, and small cove lip) if I had templates, or a dihedral Roncz.

Cheers,

 

Wayne Blackler

IO-360 Long EZ

VH-WEZ (N360WZ)

Melbourne, AUSTRALIA

http://v2.ez.org/feature/F0411-1/F0411-1.htm

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Wow thanks for all the replies. Apparently, I must be misinformed about the problems or lack of problems associated with the "GU" canard. Hopefully, with everyone's knowledge here I can gain an educated viewpoint. I completely plan to fly this Long EZ once completed "IFR." I've read of situations where people have had pitch retrimming problems in mositure or rain. Maybe someone could explain what was meant by pitch trim issues. I viewed this as a possible "ill side-effect" of the GU canard. I've even read (maybe outdated) issues as mentioned previously with takeoff. Maybe that is more related to the Cozy IV.

 

With that said my future plans for the airplane are to use it for travel and avoid airlines (I hate security now and the hassle.) I don't plan to go flying into rain intentionally, but the situation could arrise as we all know weather is unpredictable. What I want is to have a safe airplane with no ill side effects. If keeping the GU canard would be safe and worthwhile, with no ill side effects, then I'll save myself the time. However, I am completely prepared to build a Roncz in that event. I bet someone will even mention go ahead and use the GU and see if you have problems and then work them out later either by using vortex generators or if required building a Roncz then.

 

Anyway, for those that have been down this road please give me your opinions, suggestions, and experiences as they are greatly appreciated.

 

Regards,

Chris

Christopher Wise

Lake Saint Louis, MO

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  • 2 weeks later...

If you are asking about pitch trim issues---I think they are talked about all over this site. However if not...

 

With a fast longez in clear air and pitch trim full forward, my longez would take full aft trim to stay level when entering a cloud. It is a little disconcerting to throw the pitch trim around that much especially when in and out of the clouds under IFR conditions. And the full aft trim is not giving you a lot of room for climbing. For me, the VGs completely solved the problem---no pitch trim changes.

 

If you don't fly in the rain or fly IMC, you don't really need the VGs. The bad thing with VGs, is that it now takes you a lot longer to clean your canard.

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If you are asking about pitch trim issues---I think they are talked about all over this site. However if not...

 

With a fast longez in clear air and pitch trim full forward, my longez would take full aft trim to stay level when entering a cloud. It is a little disconcerting to throw the pitch trim around that much especially when in and out of the clouds under IFR conditions. And the full aft trim is not giving you a lot of room for climbing. For me, the VGs completely solved the problem---no pitch trim changes.

 

If you don't fly in the rain or fly IMC, you don't really need the VGs. The bad thing with VGs, is that it now takes you a lot longer to clean your canard.

Thank you for your replies, this is what I have read all over this site and elsewhere. The partially completed project I obtained has a completed GU canard with good workmanship. So I guess I'll have to decide if I need to build a Roncz or install some vortex generators.

Christopher Wise

Lake Saint Louis, MO

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So I guess I'll have to decide if I need to build a Roncz or install some vortex generators.

That's an easy one! Install the vortex generators. If that doesn't solve the problem to your level of satisfaction, build the roncz.

 

Keep in mind you will be trying to retrofit the Roncz into an existing plane and the problems you may experience trying to realign a new canard.

 

If you do take this route, I would suggest getting the cores from Eureka. That will get you off to a good start.

T Mann - Loooong-EZ/20B Infinity R/G Chpts 18

Velocity/RG N951TM

Mann's Airplane Factory

We add rocket's to everything!

4, 5, 6, 7, 8. 9, 10, 14, 19, 20 Done

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there's not really a lot about the savier airfoil on the net.

the wind tunnel test was interesting but I'm still not satisfied.

what is the reason this airfoil was generated?I have read on CP that the roncz airfoil has not to be used on a Veri because it produces too much lift: did Klaus modify it to let it work with the Veri's wing or was he looking for even more performance? I mean: the savier airfoil was developed(if I understand correctly) to be used on Klaus' Veri, not on a long-Ez so at the end is this airfoil superior to a standard Roncz in terms of drag or lift or just in the middle between a Roncz and a GU so that it was possible to put it on a Veri remaining far from a deep stall?

do the savier airfoil overcome the GU or the Roncz airfoil?

Roads? Where we're going we don't need roads. (Dr. Emmett Brown)

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