sonex cad-3d

[Spinnetti]

Is this from blueprints or just "by eye".... Have you shared the model anywhere? Would be fun to play with.

[Bryan Cotton]

It should be considered that the design is the property of Sonex. Reverse engineering and publishing it is not a great thing to do.

[lutorm]

It should be considered that the design is the property of Sonex. Reverse engineering and publishing it is not a great thing to do.

Just to be clear, it may not be nice to do so, but it is perfectly within ones right to reverse-engineer an airframe design, CAD it up, and give it to people. You can even sell it (as long as you don't call it a "Sonex", that would be trademark infringement.) Copyright law only prevents you from making a direct copy, i.e. you may not take the drawings and just transcribe them into a CAD program. But as long as your CAD is your own "expression" of the airframe design, it is perfectly legal. People who have purchased plans from Sonex may have agreed to further restrictions as part of the purchase contract. I don't know what the contract says.

Personally, I would love to have a CAD of the firewall forward of an Aerovee to be able to prototype things like exhausts in CAD. Sonex were not willing to share any CAD data (I've asked) but if someone were to CAD it up (accurately) it would be a very handy (and perfectly reasonable) thing to have. I seriously doubt people are going to start building airframes without buying an "authorized" set of plans from Sonex.

[daleandee]

It should be considered that the design is the property of Sonex. Reverse engineering and publishing it is not a great thing to do.

I Agree and wondered when someone would mention that fact.

Dale Williams
N319WF @ 6J2
Myunn - "daughter of Cleanex"
120 HP - 3.0 Corvair
Tail Wheel - Center Stick
Signature Finish 2200 Paint Job
166.7 hours / Status - Flying
Member # 109 - Florida Sonex Association

[inventor]

These are great drawings. I hope you do the Onex next. Amazing.

[ihab]

There is an effort out there called MakerPlane --

https://makerplane.org/

and they are trying to create a modern Open Source airplane. This means:

* The plans are in digital form using CAD tools
* The plans are freely available on the Internet
* The plans are designed for fabrication using common CNC tools like "Shopbot" CNC routers
* Anyone can make their own parts and build their plane
* Anyone can also make parts for other people and sell them to other builders

I have mentioned to them that they could do worse than to study the Sonex "as simple as possible, but no simpler" designs and create their own basic sheet metal airplane, since the commonly available 4'x8' CNC wood routers are perfectly capable of cutting aluminum.

~ HOWEVER ~

It's one thing to be inspired by the Sonex design. But copying a design that Sonex has worked on for so long verbatim is in my view not okay. I am not a lawyer so will refrain from speculating about legal issues, especially when one entity is in the United States and another is in Brazil. What you are copying is not the arrangement of a bunch of aluminum extrusions. You are copying the track record of structural analysis, aerodynamics, and testing that Pete Buck and others have done to verify that this particular arrangement of parts meets certain performance and safety goals. This is the main intellectual property of Sonex Inc., and I think you are basically taking it from them.

~ IN FACT ~

This happened to the Zenith CH701 (and other models) as well. See Zenith's own page on the matter:

http://www.zenithair.com/stolch701/7-photo-copies.html

It has not hurt Zenith's sales in the United States, so far as I know, so as long as their main market remains domestic, things are okay. I hope Sonex fares well though this.

~ BUT AGAIN ~

While I have to admire the volume of work done on this CAD model, and honestly I don't know exactly how it's going to be used, so I can't judge, I am not happy that this copy of Sonex's work is being made.

Ihab

[osvaldosurf]

My hobby is to draw, I will not pass this on to anyone. do not worry.

[osvaldosurf]

new photos