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Old 12-02-2008, 08:38 PM   #1
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What causes this?

At about 29 seconds into the run.....
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Old 12-02-2008, 09:08 PM   #2
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Drag from the Sponsons (At least that's what I think - for whats its worth - Which may not be much - but who cares)
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Old 12-02-2008, 09:36 PM   #3
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Could it be a side wind or overcorrection,
Jon will know.
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Old 12-02-2008, 09:38 PM   #4
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It could simpley be a gust of wind, at those speeds only a few inches are in contact with the water surface, so running with onl props semi emersed the craft will wander at the slightes bit of wind!!!!!!!!!!!! me tinks
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Old 12-02-2008, 10:18 PM   #5
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Watch the back of the tunnel, looks like the tunnel tab comes down and lifts the back a little too much.

Alan
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Old 12-02-2008, 10:23 PM   #6
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It Happens to me at that sort of speed - its sponson drag - trust me - im a Lawyer
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Old 12-02-2008, 10:46 PM   #7
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Looks to me like he runs across a slight 3/4 swell, maybe from a spectator boat.
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Old 12-02-2008, 11:30 PM   #8
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80% or so of the boat's lift could be aerodynamic at those speeds.
There ain't much sticking in the water, so only a minor disturbance (swell as suggest by Jon for example) is needed to unbalance the rig. Especially if one of the "dart flights" (skegs) momentarily breaks the surface.
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Old 12-02-2008, 11:34 PM   #9
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What you're talking about is the classic cat getting big air, coming down 1 side, sponson drag massively decelerating that side which puts the boat into a sharp turn & high side. Unsure what impact driver input would have to save it, but my theory is keep yer foot down and steer into it.


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It Happens to me at that sort of speed - its sponson drag - trust me - im a Lawyer
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Old 13-02-2008, 07:34 AM   #10
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It Happens to me at that sort of speed - its sponson drag - trust me - im a Lawyer


Trust me?... Lawyer?...Hahahahahaha....
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Old 13-02-2008, 10:27 AM   #11
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Prop Walking
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Old 13-02-2008, 01:20 PM   #12
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Looks to be one hell of a ride!
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Old 13-02-2008, 05:17 PM   #13
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Me think it has to do something like Alan said ,it looks like it is packing so much air , the whole boat was pushed upwards so much that all the weight was just overcome by the pressure in the tunnel,and causes to lift the lightest sponson first ,and lifted possibly the prop out of the water which causes that strange unwanted change of direction.....

When driving on the edge ,you just want your props in the water ,if the prop comes out ,it can make your day real bad.

It could also that they were testing propellors with different stern lifting abilities,or changes in the drive height ,dunno what sort drives ,could be #6 ,s or BPM drives .

Was that the boat that ran 202 mph ?
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Old 14-02-2008, 12:31 AM   #14
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Was that the boat that ran 202 mph ?
It's the Bacardi Silver boat
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