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


Jon Matcho

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i open dwg file 1-4 all empty ?

Steve, I have just opened both attachments (DWG and PDF) and all is fine. I am not sure what you mean by file 1-4 ? There is only 1x DWG file label Right Wing Templates.dwg.

 

Also, if you find the drawing is empty it could be for a few reasons. One could be the program your using does not import it properly. Make sure your program can import AutoCAD 2008 DWG files. These are different to earlier DWGs even though they have the same extension.

 

Another could be your program has certain layers hidden by default, check that.

 

Can everyone else open them successfully?

Adrian Smart

Cozy IV #1453

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This DWG and PDF are E size sheets and again all tick marks are 1" displacement. Thats my standard for full size drawings. That DWGs layout tab shows the drawing overlayed on a D size, which obviously does not fit. That will be corrected with the next upload.

 

My plan is to keep paper size to the minimum but that is a bit difficult with the root sections because I also want all templates to be one piece. No offence Burt but I hate templates that need to be glued together, although I know the reason it was done this way.

 

Vortal, I wouldn't worry about a title block at this point because there are some templates missing (like the ailerons for example). However, this sheet is getting a bit busy so there may be this, then a mirror for the left wing then one sheet that contains both wings ailerons. Comments ?

 

When they are complete I'll post them, then you can add your title block. When you do so, please try and keep the 1" marks. They will be important for the guys who get them printed at Kinkos and the like.

 

Now seems to be the time to choose a format we can all use and stick too. I'd prefer to avoid DXF for the reasons I said earlier (even those these are the most portable). Perhaps a 2000 DWG format. Almost all CAD packages can work with those.

 

I'd like to avoid Solidworks, 3DS and those sorts of formats because many people will not be able to use them. I am not saying you can't use the software or there is anything wrong with said software, I am thinking purely of easy reproduction and printing and the average guys house and Kinkos etc.

 

Obviously final output for the project could also include a PDF, but this doesn't help for collaborative efforts in producing the drawings.

Adrian Smart

Cozy IV #1453

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Adrian,

You have definitely convinced me :), It's more a matter of having a sole source that we could go to, but that's neither here nor there at this point. It sounds like you did what I was planning on doing with points and splines. I think I will probably digitize my own airfoil templates but I want to do that so I can compare differences between the Eppler 1230 and the modified one given for the plans. I plan to test them in a virtual wind tunnel (It's been a while, so I may be rusty with this stuff but I'll find out quickly!) and see how the different parameters are affected by the changes given, at least in a 2D sense. I don't necessarily want to use a different airfoil than the plans call for, but I would like to more thoroughly understand the differences between them from an aerodynamic perspective. Anywho, I would opt for DWG 2000 since most CAD can read those files in without an issue. Also, I would recommend PDF drawings be placed out there to replace the old templates since many may opt to use the traditional method. Great job! I look forward to seeing more templates in CAD soon! I looked at the plans earlier too, great job on those as well!

 

-Chris

Chris Zupp

~Aircraft Designer~

Preliminary Design Sequence I: Project Endeavour

Aeronautical/Mechanical Engineer

Private Pilot

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compare differences between the Eppler 1230 and the modified one given for the plans.

http://www.canardzone.com/forum/attachment.php?attachmentid=642&d=1175249610

 

The main change is the removal of the under camber on the bottom and the hump on the top, both near the TE. The theories it was done so far are 1. to reduce the moment coefficient, and 2. to make it easier to build and stronger in the TE area. Disregard the thickness difference. One is a true airfoil the other is a template not in the same plane as velocity (making it look thinner than the true airfoil really is).

 

I think both are suitable, believable and possible. If you compare the NACA 6X,XXX series with the 6XA,XXX series, a similar mod was done. This is documented as to make them easier to build and stronger in the TE (reference "Theory of Wing Sections", Abbott and Doenhoff, 1959 & NACA TR 903).

Adrian Smart

Cozy IV #1453

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Perhaps a 2000 DWG format. Almost all CAD packages can work with those.

100% Agree, this format is THE standard (along With the older dxf) for 2D drawings (3D models is an other story)

 

I took a lttle time this evening and compared the templates I made for BL 55 Long-EZ drawings vs. Berkut plotted CAD drawings.

The profile seems to match up pretty much from the leading edge to the spar cap. While the length was comparable, the profile of the Long-EZ drawing seems a to be quite distinguishable for the back half.

Did you compare the berkut vs the original Eppler 1230? (http://www.ae.uiuc.edu/m-selig/ads/coord/e1230.dat ; http://www.ae.uiuc.edu/m-selig/ads/afplots/e1230.gif)

Because the aft section is were the differences are between the long and the baseline 1230 as raiki was explaining...

Concerning the cad formats what i envisioned is to have the same quality (or better) than the few berkut cad drawings i have seen (http://www.berkutengineering.com/pages/support_draw1.html) applied to the Long, kinda fresh updated drawing with the 2008 technics not these late 70's hand drawings (with respect to the RAF guys)

 

Also i was thinking that one day we will have to go thru the CP's to incorporate all the changes to the drawings/build manual. by the way we also need to work on the manual, raiki (was it you?) started it, but we need to go thru thes 140 and so pages (maybe take out all the descriptif drawings and make them CAD and only keep the building sequence schematics in there...)

let me know

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  • 3 weeks later...
Pete_A said:

I have no problems thinking in either metric / imperial, but it is really hard to glue the extra 23mm ribbon of paper onto the width of an A0 roll.

Regardless of the size we are using, I am going on the assumption that most will have them printed on a 36" roll feed plotter (which is the A0 roll, even though the A0 dimensions are officially 33.1 × 46.8"). This is the plotter size I used to have access too, planning on getting another plotter soon if I can convince myself it is worth the expense.

E is 34 x 44" which will print on these plotters, I've done it heaps before.

In saying that most of my drawings are D size, however the E size is required for the wing templates.

Adrian Smart

Cozy IV #1453

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I do agree with Raiki on the fact that our main "customers" are American people,

more over the design of the EZ is all in inches, so by converting, you may induce errors.

what you can do is use decimal instead of fractions (16 2/32 vs 16.0625")

easier to use specially if you are not familiar with imperial units (all SI country, mine included) and eventually have a conversion table for imperial hardcores...

For the sheet format, As A0 doesn't fit in ANSI E and ANSI E doesn't fit in A0, i suggest ANSI D (similar to A1) if we want to keep it standard or a hybrid format(33" x 44") that fits in both A0 and ANSI E and enables us to fit in large parts

BTW 1 in = 2.54cm ;)

Ref : http://en.wikipedia.org/wiki/Paper_size

Voila!

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  • 2 months later...
  • 3 weeks later...
j hinchliffe said:

Couple of dumb newb questions,

When the fuse is stretched by six inches, does the canard move six inches forward in relation to the main wing? Have any flown with this mod?

Also, with regard to widening the fuse, do the bulkhead layups stay stock thickness or are there any extra layers added?

John

YES but....

They have been done, but no one as reported their effects on the flying (safety) characteristics of the EZ (to my knowledge).

I've read in one of the CSA newsletters that… supposedly one of the benefits of stretching the fuselage (aft of the pilot seat) is to make the EZ less sensitive in pitch... But they don't indicate if this mod as any negative effect of the plane inherent resistance to stalls. Many believe (and possibly so) that a longer moment arm could cause the EZ to exceed the critical angle of attack of its main wing and cause it to stall before the canard. This is called a deep stall and not something you would want to experience.

On a side note, be prepare to ear… don’t mess with the design or you are going to kill yourself rhetoric, without any useful info other then very basic explanation. It seems that no one that as done the longer/wider LE fuselage mod is willing to share… i) how they did it… and ii) what is the effect of the flying characteristics, if any.

It’s kind of sad when instead of enhancing the EZ (making it an even better tandem two passenger seating cross country plane) peoples are just content with solving some of its technical “faults”.

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SAF_Zoom said:

Yes that is also another problem... it is hard to distiguish genuine (knowledgable) input/infos from guesses...

Funny you should mention that. For folks who are actually knowledgeable in either engineering, design, or GOOD GA practices, it's pretty easy to distinguish the wheat from the chaff here (and on other canard oriented mailing lists and fora). The problem appears when folks who are NOT in that category think that they are, and make statements as if they are. There's an interesting article on this very subject at:

http://www.nytimes.com/library/national/science/health/011800hth-behavior-incompetents.html

I have a copy of a paper written on this subject at home, which goes into more detail, but basically, the confidence with which someone states a position is no indication whatsoever as to the accuracy of the statement unless that person IS, in fact, knowledgeable in that area, and their own OPINION of their knowledge is negatively correlated with their actual knowledge.

Basically, unless someone has proven that they know their ass from their elbow (or a hole in the ground, depending on your preferences), you should pay no attention to their own opinion of themselves.

There is, of course, no convincing incompetent people that they are incompetent, because they're incapable of understanding that fact, being incompetent :-).

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Keeping things stock is certainly the way to go as long as you can fit in the thing. Unfortunately there are very few long's over in the UK so i haven't had chance to try one for size, I'm 6' 1" tall, 195 pounds and more longer in the back than the legs.:confused: must be interbreeding! One thing i can't put up with is cramped leg room, i like to stretch out a bit. If its ok as standard then thats fine, a little extra width wouldn't hurt though. I'm assuming this is the lesser of the two evils? I wouldn't envisage widening the fuse a great amount, maybe 3 - 4 inches absolute maximum.

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Super-eze said:

Sounds like something Donald Rumsfeld said. "There are knowns and unknowns and there are known unknowns and unknown unknows" (Anyone remember that speech):confused:

Glad you chimed in Marc.

Can anyone name one good safe mod that improves the type? Then can anyone second it?

Most certainly no one would go off and build based on hear say. But it is not impossible to totally and completely verify the viability of a mod. As Marc has said before, consulting an engineering professional would be a good first start.

Would it be possible to gain a consensus on one good mod?

G'day

Upgrade from the O230 engine to an O320 is almost always agreed on as a safe mod. The other is the Roncz Canard.... I think I will make the Roncz Canard the first mod (remember to remove Chapter 10 & 11 from the TERF CD or you will get to build two Canards and Elevators. One to swear at an the second from the suplimental plans.)

Just my 2 cents. Oh, I am now building the second elevators....

Jeff

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  • 1 month later...

G'day

For all builders using the high Performance (Roncz) canard templates that are posted in this forum. Please note that no "L" jig is included in the templates.

The "L" jig is needed to attach the elevators to the canard in Chapter 11.

I have requested if anybody has a copy of the "L" jig template. I will post it if somebody provides a copy.

As a backup a "L" jig may be produced by using the under section of the elevator deflection template. I prefer not to use this backup, but think it would provide a substitute method to verify the distance from the elevator and the canard.

I welcome constructive comments and sugestions.

Jeff

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  • 8 years later...

Hi everybody, not to feel me as necroposter

But - this thread approximately died 8 years ago

Please tell me:

Reason of this situation - plans of OpenEZ from here wrong? So all of these people crushed in theyre homebuilt OpenEZ or not?

And for specification - 100HP will be enough motor power?

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An EZ needs at least 135 HP.  150-160 is ideal.

People are still building Long-EZs from plans and a few Open-EZs.   Nobody is promoting the airplanes and I suppose prospective builders do not think there is builder support but there's are plenty of EZ-builder and Cozy builder websites.  Most all the special parts are available from the Cozygirrls and Jack Wilhelmson.  The Cozy builders google group is pretty active as well as the Canard Aviators group.  All the discussion archives and newsletters are online, so there is no reason not to build one if that's is your interest.

Do a google image search for Long-ez or Cozy Mk IV.  That will bring up pictures that will lead you to builder websites.

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

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On 3/4/2017 at 1:51 PM, Enthusiast said:

So I need only 180kg capacity, and 600km radius. So I can't be good with 100HP engine anyway?

more will be very expensive for me

Oh, it would fly on 100 hp OK but the power is needed for takeoff and climb unless you can takeoff on a Freeway.  You want to climb to, right? 🙂

These days, I doubt you can build and EZ for less than $25K and $35-40K is more like it.  A good way to go is to buy a project.  You generally get a lot of materials and labor at a discount (see current ads here) and you get the builder's labor for free.  Check projects at barnstormers.com in the experimental section

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

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  • 9 months later...
On 5/17/2020 at 2:43 PM, HatSwitch said:

It's already been 14 years since this life-changing post landed, any Open-Ez projects initiated from it flying yet?

My EZ was an Open-ez although I registered it as a "Zipper".  I liked the Zipper name and wanted to respect Burt's request to not use the Long-ez name so as to shield him from liability.  Your post reminded me that I intended to send Burt a few hundred for the use of his design and, shamefully, never followed through until now.    Since then I sold the airplane.  Funny but ATC is always flummoxed by a "Zipper" that looks like an EZ so my buyer and I usually just call in as 'Long-ez XXX".    One time ATC in California looked up the registration and told him "You can't use "Long-EZ" because you are a "Zipper".    🙂

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

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