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That jacks with your brain huh? Look at the boat and the nozzle is 80% out of the water when it goes by.

Goes to show the work moving the boat is inside the pump. Or were only going 20% as fast as we could be lol
 

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Time to review the theory of jet propulsioin. Equal and oposite reaction.

You want the water discharge to be in the air so the discharge water exits the pump at the maixmum velocity to obatin the maximum thrust.

If the pump discharge exited in the water, the discharge would lose velocity and provide less thrust.

I think...... :)Unsure

Doug
 

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Kind of kills droop sales huh? :D
 

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In thrust we trust

No matter where the discharge is, the boat speed is dependent on thrust. The thrust is the same whether the discharge is under water, in the air or where ever. Thrust is the result of squirting all that water in the same direction. The water doesn't need to "push" against anything to generate thrust. The fact that the water is accelerated in the pump is what develops thrust. After the water leaves the nozzle, it doesn't matter what is hits, the work was already done in the pump.
 

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Friend just sent a pic. Yep I knew that was the case but it just screws with the brain. It's all the way out of the water and looks like the boat is on the ride plate.

Once we get this thing to load some water it should pick up quite a bit.

 

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21 Daytona
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hence the term JET:)devil Like you say it does seem a little freaky the first time you see it. On my first jet boat
I had someone drive so I could look to make sure
I didn't have any leaks on the diverter. I crawled back
over the engine cover and was like WTF??
 

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Discussion Starter #7
Since that was such a big file it zooms well.

 

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Well you can say you have no pump drag! Thats for sure! WT:)devil
 

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Discussion Starter #13
You guys need to install winches on those things.
 

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E-7 Sheepdog (ret)
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so would there be a need to have a droop AND ride plates?
They serve to entirely different purposes.

The ride plate acts as a fixed "stop" position for ride attitude, holding the hull at the desired angle.

The droop lowers the thrust line from something like centered 8" above the hull lower surface, to centered just a few inches above the hull surface, almost pushing right along the friction surface height.
 

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Yea when you step out of the boat and the tops of your feet dont get wet you know you are truely and thoroughly f^%$ed

:D

I got stuck up a little river/creek last weekend on a little exploring mission. I knew I was making progress getting the boat back to where I could jump back up on step to get out of there when I could no longer see the nozzle lol

p.s. Pushing by yourself suuuuucks
 
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