Jump to content
Jon Matcho

Introducing the Open-EZ Tandem, a 2-place tandem canard

Recommended Posts

The www.rutanaircraft.com Web site looks unchanged. What do you mean by "nothing but silence"? Did you send an order and the check is still uncashed?

If they are indeed closed, there will be Open-EZ versions of any material that is no longer for sale. However, until their Web site changes (which they have shown they can do when they moved the photo orders off their list), I don't want to put anything out that is available for sale elsewhere. AFAICT, Roncz canard and Speed Brake plans appear available.


Jon Matcho :busy:
Canard Zone Member & Administrator
Now:  Rebuilding Quickie Tri-Q200 N479E
Long-term:  Building a Cozy Mark IV

Share this post


Link to post
Share on other sites

I sent the following email to Rutan Aircraft on April 13, 2006:

 

On Apr 13, 2006, at 9:21 PM, Mary Jo and Randy Ganey wrote:

 

 

"Are these plans still available?

 

 

Roncz canard plans

$42.50"

 

 

and today, May 2, 2006 they replied with the following:

 

 

Yes, they are still available. We are preparing to close RAF, but will fill orders until we run out. If we can't fill your order we'll mail your check back.

 

Tonya, RAF

Share this post


Link to post
Share on other sites

Interesting...I guess Tonya found a box of them after I sent my email. Cool!

 

-dave


This is not a sig. This is a duck. Quack.

Share this post


Link to post
Share on other sites

They may be slow, but they're not closed just yet...


Jon Matcho :busy:
Canard Zone Member & Administrator
Now:  Rebuilding Quickie Tri-Q200 N479E
Long-term:  Building a Cozy Mark IV

Share this post


Link to post
Share on other sites

IM not going to stress to much about getting the canard plans. with all you all are doing to get the open ez plans coppied and fixed im sure the canard plans are soon to follow. im not trying to get off cheep i'll be willing to pay for them latter when i start working.

Im still trying to find a place to build mine. cant justify spending 3000 dollars on a workshop when that same 3000 could go to the plane.

 

I appreciate all your post. Whith all I have read I fell like i know exactly what I want in my bird and ready to start building.

 

Lynn

Share this post


Link to post
Share on other sites
velocity dreamer said:

IM not going to stress to much about getting the canard plans. with all you all are doing to get the open ez plans coppied and fixed im sure the canard plans are soon to follow. im not trying to get off cheep i'll be willing to pay for them latter when i start working.

Right... don't worry. They're available now if you want/need them, and I expect them to be tomorrow as well...

Quote

Im still trying to find a place to build mine. cant justify spending 3000 dollars on a workshop when that same 3000 could go to the plane.

If the workshop is attached to your house, you won't go wrong with sprucing it up. Understand that it's your most important "tool".

Quote

I appreciate all your post. Whith all I have read I fell like i know exactly what I want in my bird and ready to start building.

That's good! However, prepare yourself for becoming aware of everything you don't know. Just press through every milestone and all will be well (so I'm told...) :).


Jon Matcho :busy:
Canard Zone Member & Administrator
Now:  Rebuilding Quickie Tri-Q200 N479E
Long-term:  Building a Cozy Mark IV

Share this post


Link to post
Share on other sites

Hi All,

 

While on the subject of templates, does anyone know what Dave did on the Berkut to improve the wing airfoils. He stated way back in a magazine article that he found the EZ airfoil templates to be inaccurate and fixed them on the Berkut. I would like to do the same for my Long EZ. I know the Eppler 1230 airfoil plots are somewhere on the web but supposedly Burt used a "modified" Eppler airfoil. What was modified? How can I check the templates for accuracy the way Dave did? If we're doing it we might as well do it correctly.

 

New subject: What do the large rudder plans consist of that RAF gets $20.00 for?

 

Thanks much,

 

Bob

Share this post


Link to post
Share on other sites

The rudder plans are on the TERF CD, so if you pick that up you'll have the rudder plans as well. [NOTE: The TERF CD has no templates]

 

I believe the original rudder was a much smaller surface area than the larger rudder plans. The larger rudder is similar to what you'd see on the Cozy etc.

 

There may be inof on that set of plans as well, just haven't gotten around to reading them yet.


Bob Hassel

Cozy Plans #749

Santa Fe, NM

 

http://www.cozyworld.net

http://www.hassel-usa.com

Share this post


Link to post
Share on other sites

I have Long EZ plans so have no intention of buying the Terf CD, but I may want the large rudder plans as well as the Roncz canard. I may order them from RAF.

 

Bob

Share this post


Link to post
Share on other sites
Hookr55 said:

...does anyone know what Dave did on the Berkut to improve the wing airfoils. He stated way back in a magazine article that he found the EZ airfoil templates to be inaccurate and fixed them on the Berkut.

Which magazine and issue? Dave here (dpaton) is working on "correcting" the airfoil drawings, as does anyone who has to piece together 2 or more pages to get things to align.

Richard Riley can give the most thorough answer to your question. I understand that the only difference is that some of the Berkut wings were molded (some were foam core) and were skinned in carbon.

Quote

I would like to do the same for my Long EZ.

Do what? You don't know what, if anything, was changed with regard to the airfoil yet.

Quote

I know the Eppler 1230 airfoil plots are somewhere on the web but supposedly Burt used a "modified" Eppler airfoil. What was modified?

Do not build a Long-EZ with the "official" Eppler 1230 airfoil! Long-EZs, Cozys, and AeroCanards use the same modified Eppler 1230 airfoil. Burt Rutan modified it on purpose to improve overall flying characteristics in the context of a canard aircraft. Don't ask me what those were, but I trust Burt's judgement and would not want to mess with it -- I do not have the knowledge or skills.

Before I speculate whether Dave R. had the knowledge or skills, I'm just going to stick my neck out and bet that Dave did NOT change the airfoil and only changed the construction of the wing.

Quote

How can I check the templates for accuracy the way Dave did?

I'm not clear as to what Dave did. Assuming the article exists and said exactly what you said here, it's still not clear to me as to whether he changed the drawings/templates or changed the airfoil itself. I've read a lot (all?) of the Berkut articles and don't recall the mention so why I'm not much help right now.

Quote

If we're doing it we might as well do it correctly.

What is the problem you're looking to solve? Is there a problem beyond taping the drawings together? The problem is not in the airfoil. IMHO, that should NOT be touched.


Jon Matcho :busy:
Canard Zone Member & Administrator
Now:  Rebuilding Quickie Tri-Q200 N479E
Long-term:  Building a Cozy Mark IV

Share this post


Link to post
Share on other sites

To the best of my knowledge, the mod to the Eppler 1230 involved flattening the lower side of the TE and a few other tweaks to make the airfoil easier to construct on a flat bench in 2 car garage. The benefits on the plane were secondary and minimal. Of course, I've never seen an offical report on this from RAF, so consider it 2nd and 3rd hand, and as reliable as the game of telephone was when we were all kids.

 

:D

 

The airfoil templates underwent some distortion in the copying process, and have been distored on every single Long built since 1979 (along with almost every other template sheet), except those that took the time to calculate the distortion and redraw the airfoils completely, as I am (very few builders I'm guessing).

 

As it stands right now, the biggest component of the distortion, by an order of magnitude, is a small change in the length of the taper to the TE, and is well within the range of builder tolerance. My taped together airfoil prints are cut apart and reassembled, and are currently hanging on a wall in my garage under a sheet of vellum to be redrawn onto new paper for rescanning when I stop working until the wee hours every day here at work. The difference, aerodynamically, between my redraw and the plans airfoils will be insignificant, and my reasons for working on the airfoils are purely in the interest of completeness (they're one of the easier parts of the template concatanation to do as well). The flying character of the wing will be unaffected.

 

-dave


This is not a sig. This is a duck. Quack.

Share this post


Link to post
Share on other sites

Hi Gents,

 

I'm certainly not looking at using the original Eppler 1230. I did a quick plot last night and can see the lower surface camber that exists in the aft 30%. I'll find that article that Dave R. was quoted as seeing some inadequacies in the original printing of Long EZ wing templates that he "improved" upon.

 

I'm just interested in improvements that I can make that take advantage of newer methods without messing with "proven" designs.

 

I learned at a young age when building soap box cars (my first fiberglass exposure) that many little things can add up and win races. I lost my last race by 12" to a guy who went to the national race and placed third. :sad:

 

I'll keep monitoring for any activity on the template subject, otherwise my original plans version are just fine.

 

Thank you for the open-EZ project, this information makes me feel more comfortable with my unregistered Long EZ plans.

 

Bob

Share this post


Link to post
Share on other sites
Jon Matcho said:

Richard Riley can give the most thorough answer to your question.

And has already, for those interested in checking. See:

http://www.canardzone.com/forum/showpost.php?p=10634&postcount=5

Share this post


Link to post
Share on other sites
dpaton said:

To the best of my knowledge, the mod to the Eppler 1230 involved flattening the lower side of the TE and a few other tweaks to make the airfoil easier to construct on a flat bench in 2 car garage.

I have never heard that before. I understood that changes were made specifically to address flight characteristics. I heard this 2nd or 3rd hand as well.

Very much looking forward to your updated drawings to incorporate into the next scheduled Open-EZ revision (#6). There are several other minor modifications planned (cosmetics), which are outside of your work, which I look forward to releasing. I'll have to merge in with your work, but no problem. Take your time -- I'm in no rush, and everyone already has the ability to begin building an Open-EZ.

Hookr55 said:

I'll find that article that Dave R. was quoted as seeing some inadequacies in the original printing of Long EZ wing templates that he "improved" upon.

I imagine our next exercise will be similar to interpreting portions of the Bible. We could always ask the God of the Berkut... :)

Quote

Thank you for the open-EZ project, this information makes me feel more comfortable with my unregistered Long EZ plans.

Even if you had registered plans, they would still be as useful to you as Open-EZ plans -- no support from RAF, etc. You're in as good a shape as anyone building a Long-EZ today, registered or not.

Marc Zeitlin said:

And has already, for those interested in checking.

Geez, and I though I had the entire forum indexed in my head. Good find! Marc, do you recall the purpose of Burt modifying the Eppler airfoil?


Jon Matcho :busy:
Canard Zone Member & Administrator
Now:  Rebuilding Quickie Tri-Q200 N479E
Long-term:  Building a Cozy Mark IV

Share this post


Link to post
Share on other sites
Jon Matcho said:

Marc, do you recall the purpose of Burt modifying the Eppler airfoil?

I had heard once that it was to reduce the moment coefficient for the main wing. Having reflex near the T.E. of a wing raises the moment coefficient, and that would entail needing more canard authority (which might have an effect on deep stall susceptibility). Removing the reflex (flattening the bottom) would lower the Cm. I have no idea how accurate that account was.

Share this post


Link to post
Share on other sites
Jon Matcho said:

I have never heard that before. I understood that changes were made specifically to address flight characteristics. I heard this 2nd or 3rd hand as well.

That could be quite possible as well. Like I said, it's all heresay. The official news of the new wing design for the Long (CP23 I think) only included that it used a mod'd Eppler 1230, and that the sweep was much less than that of the Vari.

Jon Matcho said:

Very much looking forward to your updated drawings to incorporate into the next scheduled Open-EZ revision (#6). There are several other minor modifications planned (cosmetics), which are outside of your work, which I look forward to releasing. I'll have to merge in with your work, but no problem. Take your time -- I'm in no rush, and everyone already has the ability to begin building an Open-EZ.

Indeed. My mods are mainly for convenience I think. There have been thousands of planes built with the templates as-is, and they fly just fine. I just like the idea of one part, one drawing a little better.

That said, Tony has already done the work once, but those aren't nearly as Kinkos friendly as the PDFs are :D

My going will continue to be slow for another month or so due to daytime job commitments. I've given up on my original target dates, and now I'm just working to completion. I think I'll be releasing the unified drawings one set at a time, so that there is some progress to be shown, and hopefully so that folks can get what they need when they need it. The IP will likely come last however, since it's the very worst in terms of distortion, much to my chagrin.

-dave


This is not a sig. This is a duck. Quack.

Share this post


Link to post
Share on other sites

Hi Again,

 

Ok, below is a paragraph from a January 1992 Kitplanes article called Birth Of An Eagle Part 1 pg 17. This is what led me to my question back in post #58.

 

The wings are so similar to those of a Long-EZ that a pair of Long-EZ wings could be bolted onto the Berkut without modification (though it's not recommended). The greatest difference is in a carefully generated airfoil section. Ronneberg found that the Eppler airfoil presented in the original plans had been slightly corrupted in the printing process, so new templates were made from all-new plottings.

 

Soooo we would probably have to talk to Dave to get the real scoop. Maybe it was just a selling tactic. I was just curious if anyone had heard of this before.

 

Bob

Share this post


Link to post
Share on other sites

I was just curious if anyone had heard of this before.

Without seeing Burt's original master drawings, I don't think there's any way to positively know what the airfoil was supposed to look like. I've done some pretty careful analysis of the printing distortion from the templates I have access to, and the changes are decidedly minimal from what I believe is the original master, but without an accurate master to compare it to, I'm guessing.

 

Dave R. may have had access to more than I do, so I can't reliably refute that claim, not do I want to. :D

 

Does anyone have an accurate drawing of the Berkut wing profile that they could share for comparison? I'm only asking out of curiosity. I don't want to build a Berkut, but I am curious to get to the bottom of this. Any profile will do, as long as I can match it up to one of the templates I have.

 

-dave


This is not a sig. This is a duck. Quack.

Share this post


Link to post
Share on other sites
dpaton said:

Does anyone have an accurate drawing of the Berkut wing profile that they could share for comparison?

Sure... download the Open-EZ drawings. I seriously doubt that Berkut airfoil drawings/templates ever existed outside of the Berkut factory. Why would they?

Kitplanes, Jan. 1992 p.17 said:

Ronneberg found that the Eppler airfoil presented in the original plans had been slightly corrupted in the printing process, so new templates were made from all-new plottings.

Sounds exactly like what Dave (dpaton) is doing here.

Hookr55 said:

Maybe it was just a selling tactic.

I'm sure there was some value in cleaning up the drawings, but it wasn't to change the airfoil. That whole mention is more a sales tactic than anything to me.

For me, there's no point in digging into the Berkut airfoil any further, since it's the same as the Long-EZ airfoil. All the Berkut was (not to trivialize it or comparable design modifications), was a longer and wider Long-EZ made with a lot of carbon fiber. Throw a Lycoming 360 or 540 in and you're sure to go fast.


Jon Matcho :busy:
Canard Zone Member & Administrator
Now:  Rebuilding Quickie Tri-Q200 N479E
Long-term:  Building a Cozy Mark IV

Share this post


Link to post
Share on other sites

has anyone looked at the link I inserted to post 59? Just wondering if anyone agrees with this report and if so how could we use it to our advantage.

 

Lynn

Share this post


Link to post
Share on other sites
velocity dreamer said:

has anyone looked at the link I inserted to post 59? Just wondering if anyone agrees with this report and if so how could we use it to our advantage.

Yes, I read it. There's nothing new in it, except the student's lack of understanding of the fundamentals of lift. Actually, I guess that's not new - most people don't understand how Newton, Bernoulli, and/or Coanda play into the concept of lift. Mostly they don't understand that Coanda has nothing to do with lift production on a normal wing, and that Bernoulli and Newton are two different ways of saying EXACTLY the same thing.

At any rate, from the standpoint of the canard downwash effecting the AOA of the main wing, this is also no surprise, and is taken into account in ALL aircraft design, whether canard or conventional - the downwash from the front wing can ALWAYS affect the AOA of the rear wing.

While the paper is a nice science experiment, the student understands and admits that because the Reynolds number of the small model is very small, the results can not necessarily be extended to full size canard aircraft, at least with respect to the magnitude or angles at which the effect occurred.

How's that?

Share this post


Link to post
Share on other sites

sounds good to me mark. I will stick to the original design on that subject. I fly airplanes but I will never claim to be a designer or mechanic.

Thanks for the response.

Lynn

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


The Canard Zone

×
×
  • Create New...

Important Information