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  #1  
Old 01-30-2007, 12:07 PM
RatliffFranklin RatliffFranklin is offline
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Were these reverse three-pointers simply built too light?

The reverse three-pointers of John Cobb and Lee Taylor seemed to have solved the problem of blowover.

John Cobb clocked 204 mph through the kilo on his last run with Crusader.

John Cobb's Crusader

Lee Taylor clocked 269 mph through the kilo on his last run with Discovery II.

Lee Taylor Rocket Boat

The crashes occurred after the boats left the kilo.

Crusader was about 30 feet long and weighed around 5,000 lbs, but about 3,000 lbs of that was jet engine.

Discovery II was forty feet long and had an empty weight of only 2,500 lbs.

The designers had cautioned Cobb that the front planing surface needed reinforcement but Cobb believed if he ran conservatively enough the existing hull structure would be adequate. The consensus is structural failure of the forward planing surface caused the crash.

Aside from the fact Discovery II was being run in conditions too rough for the hull, the designers believe the rudder locked and submerged the left sponson enough for the stress to rip it apart.
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Old 01-30-2007, 04:38 PM
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Pericles Pericles is offline
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Location: The heights of High Wycombe, not too far from River Thames
Built by trial and error.

Pericles
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Old 01-30-2007, 05:13 PM
Dan Ellison Dan Ellison is offline
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Why aren't ATV's made as 3 wheelers any more? Because it is an unstable platform.
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Old 01-30-2007, 06:13 PM
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balsaboatmodels balsaboatmodels is offline
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Location: Boonville, MO, pop.8700; & 415 buildings on National Register
Built by Trial and Error

Is it just me, or does it some days seem more like "Error And Trial"?

FSW
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Old 01-30-2007, 07:17 PM
FranklinRatliff FranklinRatliff is offline
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Bluebird

Quote:
Originally Posted by Dan Ellison View Post
Why aren't ATV's made as 3 wheelers any more? Because it is an unstable platform.
I don't think it's quite that simple, but the fact Campbell's Bluebird achieved 200 mph not only with less effort than Cobb's Crusader but on less power and without destroying itself in the process probably says something about conventional three-pointers versus reverse three-pointers.
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  #6  
Old 01-30-2007, 07:20 PM
FranklinRatliff FranklinRatliff is offline
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WSR Boats

Quote:
Originally Posted by balsaboatmodels View Post
Is it just me, or does it some days seem more like "Error And Trial"?

FSW
I think with WSR boats most days are more error than trial.
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