3 panels plus transom = amphib airplane hull

[scottperkinsusa]

Greetings-
I want to build a hull for a small airplane and I dont think it could be
any simpler than to have two sides , a flat bottom and a transom.
I will add a long box to the rear at the appropriate angle to allow
the plane to rotate on the water when taking off and provide floatation
rear of the center of gravity.

As I have browsed through Carlson's sample hull designs, it looks
like probably the Piroque has the necessary panel layout, I would just
like to drag and drop a bit to alter dimensions and then be able to
"unfold" the panels to the flat layout and output
to a plot file I could take to the print shop and print my patterns.

It is easy enough to drag and drop in Carlsons program to alter
the shape but I dont
see where you an unfold the design for producing flat panel patterns
etc.

I've spent hours looking at many comments regarding at least fifteen
software programs here, but for something so simple as I want to do,
Is there anything more sophisticated than Carlson that will allow me
to drag and drop that will also be easier or more intuitive?
I really dont want to try a dozen programs if someone can just point
me in the optimum direction. I dont mind paying a little for the software.
Suggestions are welcome.
Thanks
Scott

[ludesign]

Originally Posted by scottperkinsusa

Greetings-
I want to build a hull for a small airplane and I dont think it could be
any simpler than to have two sides , a flat bottom and a transom.
I will add a long box to the rear at the appropriate angle to allow
the plane to rotate on the water when taking off and provide floatation
rear of the center of gravity.

As I have browsed through Carlson's sample hull designs, it looks
like probably the Piroque has the necessary panel layout, I would just
like to drag and drop a bit to alter dimensions and then be able to
"unfold" the panels to the flat layout and output
to a plot file I could take to the print shop and print my patterns.

It is easy enough to drag and drop in Carlsons program to alter
the shape but I dont
see where you an unfold the design for producing flat panel patterns
etc.

I've spent hours looking at many comments regarding at least fifteen
software programs here, but for something so simple as I want to do,
Is there anything more sophisticated than Carlson that will allow me
to drag and drop that will also be easier or more intuitive?
I really dont want to try a dozen programs if someone can just point
me in the optimum direction. I dont mind paying a little for the software.
Suggestions are welcome.
Thanks
Scott

TouchCAD is a very efficient and easy to use general purpose modeler and it should easily be able to generate you model in scale and dimensions.

TouchCAD allows you to calculate the weight and center of gravity with individual weight per area unit or point weights settings for each unit and compile it into a built in spreadsheet (or export it if you prefer that).

TouchCAD can also unfold just about anything. The entire process is dynamically linked to the 3D model and any changes done in 3D are automatically updated in the Unfold view, very useful for optimization of the use of the material. The unfolding features are highly parametric in a very wide range of ways (direction of strips, strip resolution, overlaps, automatic panel and vertex numbers, automatic coordinate measurememnts with individual settings for each panel, alignment marks, individual seam/overlap settings for each panel side , folding lines, etc). The Unfold view also allows you to move, rotate and flip the panels to allow you to generate cut out layouts to fit within a given set of sheet dimensions.

The enclosed picture is essentially a simple scribble (I think I spent something like half an hour to a hour on it) so you have to forget it if it does not look much like an aircraft.

Mor info at: www.touchcad.com

/Claes

[scottperkinsusa]

Thanks for the info on Touch Cad. To be more spetcific
what I need to do is build a piroque for the front half
of the floating airplane hull with a box structure on
the rear since no boat hull programs support steps
I dont think as are used in all pontoons for aircraft
etc.

I have attached a side view of what I was able to generate
in Carlson's hull design in about 30 minutes after first
starting the program.

#1 This shows the whole length of the hull and
#2 shows my doctored image showing the step.
#3 and #4 show the separate front half and back
half separated for design purposes.

I have no CAD background and I am afraid any CAD program
may require hundreds of hours to get this very basic
layout that I would like to build out of either plywood
or foam board sandwich.
Thanks
Scott

[Andrew Mason]

Something like this jpeg? Five minutes in Maxsurf, three trimmed surfaces.

I have uploaded this design to the Maxsurf Academic sample designs page if anyone wishes to download it.

[scottperkinsusa]

Andrew- that is really a beautiful rendition of what
would be a sleek hull for an amphib plane ... I was actually
thinking flat bottom to simplify building but you may
have changed my mind. I do know that like airboats
a perfectly flat bottom requires the least possible power
to plane on. I never plan to see any rough water
in my airplane so a flat bottom will be ok.
Thanks for the inspiration.
Scott

-------

Originally Posted by Andrew Mason

Something like this jpeg? Five minutes in Maxsurf, three trimmed surfaces.

I have uploaded this design to the Maxsurf Academic sample designs page if anyone wishes to download it.

[ludesign]

Originally Posted by scottperkinsusa

Thanks for the info on Touch Cad.

I have no CAD background and I am afraid any CAD program
may require hundreds of hours to get this very basic
layout that I would like to build out of either plywood
or foam board sandwich.
Thanks
Scott

TouchCAD is very easy to use, and the user interface is close to many standard graphics programs. To see some very quick modeling I suggest that you download the yacht design tutorial movie from the TouchCAD web site. www.touchcad.com

[Andrew Mason]

Scott

Obviously you need to be very careful with the design of floatplane floats, your life could depend on it. Whether you are using a stepped or unstepped bottom, I suggest you research the subject carefully as the location of any step and the angle of attack of the planing surfaces will be critical to perfomance and safety.

I did a quick search and didn't find much for full size floatplanes, however the R/C modellers have a lot of info. A good starting guide is at -
http://www.stenulson.net/rcflight/watrfly2.htm

also some float manufacturers-
http://www.ultralightfloats.com/water_article.htm
http://www.zenithair.com/kit-data/floats.htm
http://www.familyairtours.com/page14_aeroset.html

regards

Andrew

[scottperkinsusa]

Those were some nice links and thank you for sharing.
Actually my inspiration is from severa of two of the best
photo galleries for small seaplanes on the internet.

http://vulatalk.zdwebhosting.com/pic...oats/Page.html

http://vulatalk.zdwebhosting.com/pic...ater/Page.html

http://vulatalk.zdwebhosting.com/pic...ane/index.html

http://vulatalk.zdwebhosting.com/pic...fish/Page.html

I did study aerospace engineering and have had success
in designing planes, but I am brand new with the boat
hull activity.

Sadly, Maxsurf is over my budget for this one time project.
What a beautiful job it does however.
Thanks again
Scott