# Three Point Hydroplane Questions

Discussion in 'Boat Design' started by aaronhl, Aug 12, 2012.

1. ### FranklinRatliffPrevious Member

Air Trap

A clearer example of a hydroplane with an air trap.

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### aaronhlSenior Member

Any more tips? Anything else you think I'm missing?

3. ### FranklinRatliffPrevious Member

I'm about out of tips, but I don't see anything big you're missing.

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### aaronhlSenior Member

Still lost on how to set Angle of Attack for both the sponsons and engine tub. Is there a calculation for determining the engine carrier length behind the sponsons?

5. ### FranklinRatliffPrevious Member

3 degrees AoA for the sponsons INDEPENDENT OF ANYTHING ELSE. For prop-riders the prop is the third point of suspension.

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### aaronhlSenior Member

Where do I measure the 3 degrees from? What do you mean independent of anything else? And how do I set the tub angle of attack, measured from where?

7. ### tunnelsPrevious Member

need to read and take note !

After reading the information in the fast electrics hydropanes just about every question you have is answered in there ! almost everyting i have discribed is in there . you need to read and re-read very carefully . its dicribes just about every senario !

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### aaronhlSenior Member

Not quite, I still don't know how to measure the angle of attack. The picture on the website shows to measure from the water surface to the bottom of the sponson. How accurate can that be if the bottom of the sponson is curved and you can see a different degree from different spots on the bottom??????????

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### aaronhlSenior Member

Found this and if it is correct to read the angle of attack on the few aftmost inches of the sponson, I now know how to set it.

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WRONG!

11. ### tunnelsPrevious Member

this is all going no where !! interesting but !!!

With all the pictures is see aerodynamics are no where to be seen Its like a wedge shaped brick so to speak . square corners ,flats , sharp points trailing ends that are just cut off etc etc There no areodynamics !!! what dont you understand !!!

Make shapes that slips throught the air and it will go faster even if its touching the water!!!! make it fly so its not touching the water it will go even faster still .

NO mater how high you drop a brick from it will get to a speed and wont go any faster but give it smooth flowing lines and it will pass any brick that gets in its way !!

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### aaronhlSenior Member

Post some pictures of aerodynamic shapes. Have any designs/hulls you can refer to specifically?

13. ### tunnelsPrevious Member

Im fresh out of spoons at this moment !!

How bigger spoon do you need ???
go look at a family car !!:?:
Go look at a sports car back, front, side ,where ever !!:?:
how many flat square corners do you see?
go look at a motor bike they have flowing lines and beautiful shapes !!!
Find a aeroplane and look at it the wings where thy meet the fusklage the shapes everything is aerodynamic . even the little wing right at tha end of the wing has a purpose !!! its something new ! do you know why its there ?? take a guess and find out !!!
A model T was a brick and the brick shape stayed with us for many years . then as cars got faster the wind noise got louder . do you understand the shape of most new cars today ?? why are they down at the front and up at the back ?? the faster they go what happens ??what is the design shape of the car doing ?? guess !!
all these things are because of speed increase and the faster the car goes the more traction it needs ,so with design and areodynamics its ?? guess !!!use you imagination !! look around you

14. ### FranklinRatliffPrevious Member

AoA

Your own picture clearly shows where to measure angle of attack.

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### aaronhlSenior Member

What about steps on the tail aft end?

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