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Flying boat hull design

Flying boat hull design

Flying boat hull design

I am involved, with a friend, in the design of a two place flying boat for recreational purposes. I have some experience in aircraft design but nothing to do with flying boat hull design (and even do not know if and what university has a flying boat design course!).
I have looked around and found something on my books and on internet (some very old NACA reports and guidlines on step position), my question is: is there any book and/or software which gives a complete rendition for this kind of design, which cover all the aspects of hydrodinamic design and eventually of the accompaning loads on water surfaces?
Thanks for helping

RE: Flying boat hull design

The bottom is not part of an airplane; it's part of a boat.

So that's where you look.

I'd start with most any book by Dave Gerr.  His stuff is accessible to both engineers and civilians.


Mike Halloran
Pembroke Pines, FL, USA

RE: Flying boat hull design

Thank you looking for his work.

RE: Flying boat hull design

 Look into FAR 25, you will find how to calculate waterloads according to FAA standards.
Simple and conservative.


RE: Flying boat hull design

Robonave Look for:



NAS807 Specification - Twin Seaplane Floats (Rev. 1)  

Regards, Wil Taylor

RE: Flying boat hull design


Long time ago I read a very interesting ERNEST STOUT´s article about a modern flying boat design.


Some improvements however have been demonstrated by the use of high length-to-beam ratio hulls and this was researched in some depth prior to 1950 and is well reported in "Development of High-speed Water-based Aircraft", by Earnest G Stout in the Journal of the Aeronautical Sciences Vol. 17 August 1950. This discusses tests on hulls with length/beam ratios of up to 12 though the advantages indicated were little exploited as there has since been little seaplane development work. The U.S. Navy's flying boat XP5Y-1 (first flown in 1950) had a length/beam ratio of 10. However, it had all the above-mentioned features of a conventional seaplane.


RE: Flying boat hull design

Hello robonave,

I think that the Roskam books have it.
For shore I know that they have some WIGs analysis. So, you can find some "wing in ground effect" data



RE: Flying boat hull design

wing in ground effect is worth looking at, unless you truly need the altitude to pass over obstacles.

RE: Flying boat hull design

if you want to call it somthing its a flying vessel, flying boat just doesnt sound right

RE: Flying boat hull design

Wing In Ground Effect probably has some recreational potential.  It has/had commercial potential, too, in the USSR mostly.

Google 'ekranoplan' or 'ekranoplane' for a lot of interesting reading and photos of really strange looking vehicles, not quite flying boats, some small and some very large.


Mike Halloran
Pembroke Pines, FL, USA

RE: Flying boat hull design

Mike- A ground effect aircraft for recreation is just asking for lawsuits.  All sorts of enthusiasts crash their homebuilt/experimental aircraft due to errors exhasberated by low flying.   

RE: Flying boat hull design

Please note that I didn't say it was a >good< idea.

My limited reading of ekranoplan history says they even have some unique ways of crashing, in addition to all the usual airplanc and boat crash modes.

So, yes, any commercial endeavor would necessarily include substantial insurance coverage.

Sure sounds like fun, though...


Mike Halloran
Pembroke Pines, FL, USA

RE: Flying boat hull design

Um, I'm pretty sure I've seen WIGE racing or similar on TV, not sure if they were all home built or what.  The test guy at my last employer was building one, or a scale model or something.

I will say these were more 'boat like' than 'plane like' but did rely on 'wings' lifing them off the surface to reduce drag although I think the propellor maybe hung down into the water, I can't remember for sure.


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RE: Flying boat hull design

 As long as the propeller (or whatever) reacts with the ground or water it is not an airplane, legally.  

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