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single rudder?

Slidin Gator

Well-known member
Rudder picture to remember Daddy and Momma Feb 06 2016 Lake Okeechobee
Army,

I do remember the story of your folks, I love watching eagles soar, two definitely deserve a canvas like a big ole single airfoil rudder.

But first, I want to say that this boat in the classifieds has the correct set of dual airfoil rudders. It's a tradeoff, but these things work well for sure.

ffd63416-79b7-4606-b010-72d0ede8430d-6950b2d4-1024x768.jpeg
 

Slidin Gator

Well-known member
So I busted out an old book from the 70's. The pictures are still stuck in my mind and remain valid, so I might as well share.

Fluid Mechanics Cover.jpg
 

SHEPHERD OF CHRIST

Well-known member
Aerodynamics is a very interesting subject I appreciate the kind words also the inspiration for the picture is from Isaiah 40:31 and I always say to people peace be unto you which is to say let God give you rest in your times of trouble
 

Slidin Gator

Well-known member
Vacuum (lift) is how wings works, it's how airplanes fly. It's how airboat props make thrust. My rudders are 4' tall by 42" long. That is 2,016 in^2 of rudder area. Ambient air pressure at sea level is 14.7 PSI. If I draw just 0.1 PSI of vacuum on average on the back side of my prop I net 2016 * 0.1 = 201.6 lbs of force.

Now look at where that force is applied. With smaller rudders the turning force is closer to the transom. The larger the rudder, the further stern of the transom the rudder applies it's force. That is the leverage part. It's the same reason these rudders suck in a cross wind.
 

Slidin Gator

Well-known member
I idle when the frogs are thick, and frog on a plane when they are not. And I'm not talking about tearing the rudders off the boat, just feeling stuff hit them hit them. I think it's sporty to get them when running in at cruising speed. I admit I don't get as many at that speed but I am usually done by that time.
I do understand, I own 4 rudders and only 2 of them don't have any dents, because I haven't run em yet. I hit more trees and trailers in my yard moving crap around than I do in the woods though.

IMG_9696.jpg


IMG_9700.jpgIMG_9698.jpg
 

Slidin Gator

Well-known member
Aerodynamics is a very interesting subject I appreciate the kind words also the inspiration for the picture is from Isaiah 40:31 and I always say to people peace be unto you which is to say let God give you rest in your times of trouble
Army,

Thanks for the opportunity to cover a subject of interest to me. Everyone can see the same thing for themselves by running up a boat near a leaf fire. Visual aides are always best :)

Isaiah 40:31 is important to you so it should be included that in your rudder graphic.
 

SHEPHERD OF CHRIST

Well-known member
A couple of pictures I done a while back I think represents very well hopefully one day 🙏✝️ the boat will be called Riding with Jesus
 

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SHEPHERD OF CHRIST

Well-known member
The day I receive my dad's flag I've been trying to figure out a way to put the picture of his flag on a set of rudders one day can't seem to come up with an idea
 

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