Torque Roll
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Torque Roll
Can anyone explain torque roll in a quick easy way. I have reviewed several past posts and just can not figure out a way to explain it to non airboaters. I'm sure some of our experienced members can do it in simple terms.
Thanks,
Swampsaver.
Thanks,
Swampsaver.
- SwampMatt
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Re: Torque Roll
Easy. FOR EVERY ACTION THERE IS AN EQUAL AND OPPOSITE REACTION.
So when your motor spins your prop one way, it also tries to spin/roll the boat the other way.
It don't get more simple than that!
So when your motor spins your prop one way, it also tries to spin/roll the boat the other way.
It don't get more simple than that!

- Whitebear
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Re: Torque Roll
Its basic for every action there is an equal and opposite reaction. Remember old science class in school? When you spin up ethe mass of the prop and motor the hull has to resist the spin in the water. Since water is a liquid the hull will roll to the opposite side from the prop spin up. It can VERY pronounced or bearly perceptable depending upon several things. Prop length and bite, hull width and chine design as well as overall weight, prop and engine acceleration as well.
Know how if ya put your hand on the fender of a car and stomp the gas you can feel the car rock? Thats exactly whats happening in the boat, except the car is on wheels and the boat is in the water and moves in the water.
Scotty
Know how if ya put your hand on the fender of a car and stomp the gas you can feel the car rock? Thats exactly whats happening in the boat, except the car is on wheels and the boat is in the water and moves in the water.
Scotty
"The Constitution is not so the government can restrain the people, it is so the people can restrain the government." Patrick Henry
The government cannot give anything --
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The government cannot give anything --
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Re: Torque Roll
There was a video of waterthunders boat torque rolling here a few months ago that I have been looking for. A picture is worth a thousand words and will explain it fully. Hopefully someone can repost it.
Tim
Tim
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- SwampMatt
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Re: Torque Roll
Oh yeah, the motor.
The motor has parts that are spinning also, (not just the prop) so there is some torque roll for that too. But I think most of the "torque roll effect" we see in airboats comes from the spinning mass of the prop.
If a boat is direct drive, then the torque roll is the total of the prop and motor (since they are both spinning in the same direction)
Same with a belt drive.
BUT, with a (normal) GEAR drive, the motor and prop spin in opposite directions - so you get less torque roll because the torque roll from the motor CANCELS OUT a little bit of the torque roll from the prop.
You've got some inquisitive non-airboating friends!!! LOL Hats off to you for educating the non-airboating world out there.
The motor has parts that are spinning also, (not just the prop) so there is some torque roll for that too. But I think most of the "torque roll effect" we see in airboats comes from the spinning mass of the prop.
If a boat is direct drive, then the torque roll is the total of the prop and motor (since they are both spinning in the same direction)
Same with a belt drive.
BUT, with a (normal) GEAR drive, the motor and prop spin in opposite directions - so you get less torque roll because the torque roll from the motor CANCELS OUT a little bit of the torque roll from the prop.
You've got some inquisitive non-airboating friends!!! LOL Hats off to you for educating the non-airboating world out there.
- Whitebear
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Re: Torque Roll
Can anyone explain torque roll in a quick easy way.
I fear we have WAY overdone it. Sorry about that
Scotty
I fear we have WAY overdone it. Sorry about that

Scotty
"The Constitution is not so the government can restrain the people, it is so the people can restrain the government." Patrick Henry
The government cannot give anything --
that they have not first taken from someone else.
The government cannot give anything --
that they have not first taken from someone else.
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Re: Torque Roll
Prop and boat playing Tug of War, Boat is winning barely. 

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that likes to have fun !

http://www.jollyrogeradventures.com
that likes to have fun !

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- Waterthunder
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Re: Torque Roll
Simple physics just as with everything else water, electricity and fluids. Everything always takes the least path of resistance if it’s easier to roll a boat on it’s side then it is to go forward it will roll till the point it’s easier to go forward. Torque roll is a challenge to manage or overcome!
THE PROOF IS IN THE PROP!
"If you copy someone you will only achieve what has already been done."
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"If you copy someone you will only achieve what has already been done."
http://waterthunder.com/
321-508-5316
- airduds
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Re: Torque Roll
Think what a conventional helicopter would do without a tail-rotor
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- SwampMatt
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Re: Torque Roll
And if you wanted to do the math, it's probably the good ol' f=ma equation Force = Mass x Acceleration
but it don't get much more simple than: for every action there is an equal and opposite reaction.
but it don't get much more simple than: for every action there is an equal and opposite reaction.
Re: Torque Roll
here is a pic of torque roll.




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Re: Torque Roll
Thanks to all of you. I have some good answers now.
SS
SS
- Waterthunder
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Re: Torque Roll
Here is a boat that has a slight torque roll problem!

THE PROOF IS IN THE PROP!
"If you copy someone you will only achieve what has already been done."
http://waterthunder.com/
321-508-5316
"If you copy someone you will only achieve what has already been done."
http://waterthunder.com/
321-508-5316
- MYDIXIEWRECKED
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Re: Torque Roll
Dave, you ought to install a self leveling seat system for Jimmy! then he could ride it out!



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Owner camp 9 1/2 in beautiful 3A south, Everglades