CAD drawings for Long-EZ. (Link to ez.org)

[Voidhawk9]

8 hours ago, hdmx said:

By the way does anyone here have the installation instructions of the infinity retractable landing gear?

https://infinityaerospace.com/product/featured/landing-gear/
The info pack is basically the instruction set in a ring binder.

[hdmx]

I worked a bit on my model. Included some significant modifications so it can probably not be seen as a "stock" Long EZ anymore. However most of the structure (Fuselage, most of the center section spar, most of the wing) stays the same. I plan to include blended winglets, a rounded nose, streamlined canopy, and maybe a retractable landing gear.

To actually confirm the measurements and models, I intend to build this project beginning next year. This will also include building jigs and models (for example to fabricate the new canopy). If someone is interested in building a similar project, it might be possible to re-use these jigs and models

[Voidhawk9]

I simulated a similar canopy for a Cozy. The additional side area that far forward noticeably reduces yaw stability. FYI.
You could enlarge the winglets to compensate, I suppose, but it all extra weight and wetted area. I have elected to go for a smoothed but stepped nose.

[hdmx]

vor 53 Minuten schrieb Voidhawk9:

I simulated a similar canopy for a Cozy. The additional side area that far forward noticeably reduces yaw stability. FYI.
You could enlarge the winglets to compensate, I suppose, but it all extra weight and wetted area. I have elected to go for a smoothed but stepped nose.

Yes, the projected area is is increased roughly 8% in comparison to the original canopy and nose. The shallower angle of the canopy might be an additional problem regarding visibility. What are the results of your analysis with directional stability? I just don't like the looks of the original canopy/nose

[Voidhawk9]

More important is the increase in projected area ahead of the CG, which will make that number bigger.

My analysis is X-plane based, which while imperfect, I have the experience (20+ years) to have high confidence in it.
Besides which, Marc Zeitlin has reported real-world flight experience showing the same thing.

Improving the aesthetics is certainly a worthwhile thing to do in my opinion, but not at the cost of noticeably worse handling and performance. Indeed, my goals are to improve handling and performance, which includes developing new airfoils more suited to the much higher performance anticipated compared with the original Long-Ez.

[zolotiyeruki]

On the subject of blended winglets, you may want to take a look at a presentation by Marc Zeitlin about his experience doing them on an eRacer: http://www.cozybuilders.org/Oshkosh_Presentations/2007_Blended_Winglet_Eracer.pdf

@Voidhawk9 are you documenting your airfoil changes anywhere, like on HBA?  I'd be interested in learning more.

[Voidhawk9]

I haven't, yet.

Re-airfoiling a canard comes with more considerations and risks than on a more conventional aircraft. Thus I want to be wary about sharing and having people who don't fully understand trying them without recognizing the significance of the mod and performing a thorough test campaign.

But perhaps I can share some performance predictions vs stock sometime.

[Pierre Andre]

René, I also have a Catia V5 CAD model, you can contact me if you want.

Pierre, Stuttgart

[DJBrant]

Home hobby CNC tables are not uncommon these days.  I took the RONCZ Canard Template sheet (the one done in vector output) and made spot-on perfect hotwire templates (see photo).  However, when I looked into tracing out the other templates in the package that were scanned, I quickly noticed the scale on each page is inconsistent and specifically one page shows a bracket 3" left to right and another bracket that is 3" up and down.  If you print the page scaled so that one of the 3" dimensions are correct, the other one is out by a small but non-trivial amount. Dimensioned parts are not a concern but there are jig templates with curves that won't match up properly.  I could independently scale each axis but is that the only page that is borked?  I don't know and it's difficult to tell.

The question I have is - is there a set of dxf, svg or other fairly universally accepted vector versions of all the templates for the RONCZ canard in the community? 

-Darren

[sixfivelrp]

If you are trying to make parts from the work instructions just use them as a print. The open eze package has everything needed to build a fine aircraft.