Kaos (oz6251)


Kaos (oz6251) by Joe Bridi 1970 - plan thumbnail

About this Plan

Kaos 60. Classic pattern plane for 60 power. Wingspan 59 in, wing area 644 sq in.

Quote: "World renowned R/C flier Joe Bridi presents his pattern contender for 1970. Although it may look like its famous predecessors, a closer look will show you why the Kaos will be the year's top multi.

The Kaos may look like its predecessors, notably the Sun Fli III (oz7716) and Sun Fli IV (oz3946), but a line up of minor changes have been made to improve the performance of this model. We have gone to a double taper wing to help the rolls and, by doing this, we also improved such maneuvers as the slow roll, 4-point, and the spins. The root rib is a 19% thickness and the tip rib is 17%. Again, like the Sun Fli IV, the top of the wing, at the spar, should be flat across the entire span - if dihedral is used the model will have the tendency to roll out on the knife edge and the vertical portions of the 4-point rolls.

We were experiencing some warping in the elevators on the Sun Fli, so we increased the thickness to eliminate that problem. The rudder rate was also increased for obvious reasons. There never seems to be enough rudder area for maneuvers.

Again, 3/16 in full length balsa sides were used. We haven't experienced any need for doublers when using 3/16 thick stock. The top block is built up with 1/4 x 3/8 strips and 1/4 sheet. This was done in order to reduce weight and the overall cost of construction.

The wing spars are grooved for each rib as illustrated on the plans by the dotted line. We used the same procedure tor the leading and trailing edges. This makes for a sure-fire alignment of all ribs. A radial saw is a handy tool for the notching of the spars, trailing and leading edges. If at all possible, use this method even if you have to borrow your friend's saw..."

Update 15/05/2017: Added left wing plan view, ready to print, thanks to Doug Smith.

Update 05/01/2021: Replaced this plan with a clearer copy, thanks to theshadow.

Direct submission to Outerzone.

Update 05/02/2021: Added PDFvector plan tracing and CAD files, thanks to AlanSinclair.

Supplementary file notes

Left wing plan view.
PDFvector plan tracing.
Previous scan version.

CAD file

This plan is available for download in CAD format.


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Kaos (oz6251) by Joe Bridi 1970 - model pic


Kaos (oz6251) by Joe Bridi 1970 - pic 003.jpg
Kaos (oz6251) by Joe Bridi 1970 - pic 004.jpg
Kaos (oz6251) by Joe Bridi 1970 - pic 005.jpg
Kaos (oz6251) by Joe Bridi 1970 - pic 006.jpg

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User comments

I just got started on my next project, a classic Kaos 60. I used the RCM plan because it has the ribs printed on the plan, whereas the Great Planes plan omits the ribs. They do not interchange and the RCM ribs do not fit the Great Planes version. The RCM ribs are not perfect either but close enough, fuselage sides need to be modified slightly to fit the root rib. You will notice only the right wing is shown on the plan. I was able to use Gimp to print the left wing view. You need to IMPORT the PDF file into Gimp, CROP out the right wing, FLIP HORIZONTAL, then EXPORT as a PDF. Give it a new name and you're ready to print. Also, it was easier for me to crop and print each part of the plan instead of taping the entire giant sheet together and cutting it apart, more accurate that way. Sounds like a whole lot of trouble but once you have it figured out, it's easy. Included is the left wing plan view, ready to print [supplementary file].
DougSmith - 15/05/2017
My latest project, a Kaos, is coming along. Once the wing is finished, every project moves closer to the first flight. I completed the wing covering last night with the wingtips, always a tough thing to finish [more pics 003]. Compound curves on the tips present a challenge for most any covering material, but Doculam handles it better than most. I got it all done with no wrinkles at all. Doculam on the wing is done but not yet shrunk tight except for the tips, will turn water clear with heat. Then I'll have to build the ailerons and hinge them before paint, using more Doculam for the hinges, no gap that way. The wing has to be finished before fuselage construction can begin because the RCM Kaos plans were not all that good, ribs didn't fit the fuselage very well. I'll have to re-draw the fuselage plan to fit the finished wing, not a big deal. Next time, I'll use the Great Planes plan and draw my own ribs. I'll use my usual spray can Rustoleum, best I've found for Doculam, trimmed with a second color masked off with vinyl shelf paper. Stay tuned for more pix as construction nears completion.
DougSmith - 13/06/2017
I built this Kaos for an Avianca airline pilot [main pic, 006]. He is practicing with the extraordinary model for the Senior Pattern contest early next year here in Bogotá. It has a JETI radio control and an OS.65 engine. All balsa and very light. Thanks, EDUARDO (Colombia)
Eduardo - 29/11/2022
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Download File(s):
  • Kaos (oz6251)
  • Plan File Filesize: 389KB Filename: Kaos_60_oz6251_.pdf
  • Supplement Filesize: 368KB Filename: Kaos_60_oz6251_article.pdf
  • Supplement Filesize: 1133KB Filename: Kaos_60_oz6251_previous.pdf
  • Supplement Filesize: 470KB Filename: Kaos_60_oz6251_RCM_Wing_Left.pdf
  • Supplement Filesize: 646KB Filename: Kaos_60_oz6251_vector.pdf
  • CAD Zip Filesize: 302KB Filename: Kaos_60_oz6251_cad.zip
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