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Old 11-03-2008, 01:59 PM   #11
[R-DEV]Masaq
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Default Re: is that real ???

Yeah, that's all they've done.

Pop the engine into neutral briefly, the boat will continue forward on momentum alone.

Then slam it into reverse, the engine bites hard and the bow comes down.

It's not good for props or the engine, but anything that basically runs on a big outboard like that will do it.


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"That's how it starts, Mas, with that warm happy feeling inside. Pretty soon you're rocking in the corner, a full grown dog addict, wondering where your next St Bernand is coming from..." - IAJTHOMAS
"Did they say what he's angry about?" asked Annette Mitchell, 77, of the district, stranded after seeing a double feature of "Piranha 3D" and "The Last Exorcism." -
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Old 11-03-2008, 02:03 PM   #12
thebusdriver
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Quote:
Originally Posted by [R-DEV]Masaq View Post
Yeah, that's all they've done.

Pop the engine into neutral briefly, the boat will continue forward on momentum alone.

Then slam it into reverse, the engine bites hard and the bow comes down.

It's not good for props or the engine, but anything that basically runs on a big outboard like that will do it.
right, i rly don't wanna be a smartass here, but assuming the boats work similar as cars ... well .. put in reverse when ur drivin at 30mph !?!

edit: kk ... what you posted seems somewhat logical
thank you
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Old 11-03-2008, 03:48 PM   #13
[R-DEV]Masaq
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Default Re: is that real ???

Boats don't work similar as cars - the propellor isn't in the kind of friction-based contact with the water is as a car's wheel. You can spin a prop backwards whilst the boat is going forwards just fine - the prop will shake and cavitate and it's not good for it, but it can be done - because the prop moves through the water as well as moving water through it, if that makes sense.

It's like reversing thrust on a jet, for example.


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"That's how it starts, Mas, with that warm happy feeling inside. Pretty soon you're rocking in the corner, a full grown dog addict, wondering where your next St Bernand is coming from..." - IAJTHOMAS
"Did they say what he's angry about?" asked Annette Mitchell, 77, of the district, stranded after seeing a double feature of "Piranha 3D" and "The Last Exorcism." -
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Old 11-03-2008, 09:37 PM   #14
Nick The Bubble
Default Re: is that real ???

you don't need to put the boat into reverse anyway, as long as it has enough weight on the front (a few men with fixed guns and ammo should do) the front will sink and it will stop very quickly. the cross section of the bottom of the boat is quite a large area and simply acts as an air brake would, as said earlier. think about the amount of water needing to be moved before and during while the boat is planing.
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Old 11-03-2008, 10:54 PM   #15
[R-DEV]Eddie Baker
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Default Re: is that real ???

Quote:
Originally Posted by [R-DEV]Masaq View Post
Boats don't work similar as cars - the propellor isn't in the kind of friction-based contact with the water is as a car's wheel. You can spin a prop backwards whilst the boat is going forwards just fine - the prop will shake and cavitate and it's not good for it, but it can be done - because the prop moves through the water as well as moving water through it, if that makes sense.

It's like reversing thrust on a jet, for example.
Those boats are powered by waterjets rather than props.
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Old 11-03-2008, 11:42 PM   #16
Pariel
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Quote:
Originally Posted by [R-DEV]Eddie Baker View Post
Those boats are powered by waterjets rather than props.
That is pure sex.

I forgot that they do that in the military.
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Old 02-17-2010, 04:36 AM   #17
hartbilt
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Default Re: is that real ???

Answer to the question of HOW DO THE BOATS STOP SO FAST?? FIRST, understand that the Special Operation Craft-Riverine (SOC-R) is a "Jet-Boat" meaning it is propelled by Twin Hamilton HJ292 waterjets that are powered in this case by twin 440 HP Cat. Turbo Diesels or by twin Yanmar diesels. Think of a "JET-SKI", same concept just biggie sized. Basically a water jet is a turbine prop inside a housing that moves the water, the benefit being that it can operate in shallow river environments without the worry of outboard propeller damage, the Water-jet can also provide precise directional control (steering) for the vessel by directing exit flow of the nozzle ( think of F-22 thrust vectoring if ur familiar). Now the way the SOC-R is able to go from a cruising speed of 40+ knots to a complete stop in about 1-1/2 boat lengths, is the BUCKETS SYSTEM. As the name implies, there are basically buckets located over each jet outlet, when activated the buckets drop down over the jet outlets acting like brakes or a sea anchor and redirecting the thrust of the waterjets. SO there you have it, A BOAT WITH BRAKES, as the SWCCs say.

This is the waterjet used on this craft
waterjet.jpg
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Last edited by hartbilt; 03-24-2010 at 03:28 AM..
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Old 02-17-2010, 07:04 PM   #18
master of the templars

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Default Re: is that real ???

um thanks... I have been totally killing my self since 2008 thinking about this

Make nukes, Not war

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