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-   -   Can a cat boat be built with a blow out hinge flap to prevent a blow over? (https://www.offshoreonly.com/forums/general-boating-discussion/265483-can-cat-boat-built-blow-out-hinge-flap-prevent-blow-over.html)

Gripenland 11-11-2011 12:53 PM

I didn't say it was useless. I said I didn't see a reason for crumple zones.
Please enlighten me of the benefits?

I also wonder if a experienced racer and boat designer automatically becomes a good safety engineer?

Is there any photos of the new MIT safety cockpit?

schnydo 11-11-2011 01:12 PM


Originally Posted by Gripenland (Post 3547595)
I didn't say it was useless. I said I didn't see a reason for crumple zones.
Please enlighten me of the benefits?

TO CRUMPLE

Raylar 11-11-2011 01:13 PM

If as many race boats do, the boat rolls instead of blow over or does an end to end swap as many times occurs in crashes this type of device might not solve all the problems as neither would a air release flap only So the Need for Roll Protection structure and reinforcement or Crumple Zones will many times be needed. As it is usually occurs in lots of crashes the type of control loss does always foretell the injuries or severity of injuries to the occupants.

Best Regards,
Ray @ Raylar

Gripenland 11-11-2011 01:19 PM


Originally Posted by schnydo (Post 3547604)
TO CRUMPLE

I see :lolhit:

PhantomChaos 11-11-2011 10:33 PM


Originally Posted by schnydo (Post 3547604)
TO CRUMPLE

Nice way to discuss. :bigbird::bigbird::bigbird:

WildThing47 11-12-2011 01:18 AM

this is an insult to the lives lost in this weekend's events...we had people lose their lives doing what they love, do not make jokes or go on about what YOU would've done to prevent it...it's in poor taste...god bless and take a moment of silence in your day to remember those who push the envelope , they sacrifice, we didn't, a post doesn't count....give some RESPECT

BROWNIE 11-12-2011 06:09 AM

Catamaran aerodynamics
 
When the boats finally got past 100, Cougar spent some time on the subject. Back then we had rules which kept engine HP down to a reasonable level, since we had to go a couple of hundred miles sometimes. We built a new 38' aluminum cat for Ted Toleman to break the "Ton" (100 mph). It was the first cat with the last bottom panel parallel with the datum line, which allowed the boat to "trim" by rotating on its center of balance. It was possible to raise the bow without raising the entire boat. Still didn't make 100. We built a 12' wide, 4' long slot/flap, end plate NACA 29 aluminum wing to mount above the CG. We ran the boat at its best performance, 98 mph, with a broom stick with lints taped to it, and discovered that the lowest level of 'clean air' was 7 feet above the deck. We mounted the wing there, and set the wing at 3 degrees plus angle, and the flap at 20 added degrees, down. According to the NACA book, that wing would provide 1260 pounds of drag, and 4,400 pounds of lift. We considered supplying oxygen to Smitty and Ted for the record run, since they might not be able to breathe at those speeds. It ran 99. Sonny Levi, who has an aero degree allowed as how the only benefit of the wing was raising the drag center.

In my opinion (bear in mind that my earlier training was skipping flat rocks on the Wabash river), aerodynamics of a big fast cat 'in trouble' is more akin to ditching a plane than regaining any semblance of control, man, computer, automatic or whatever. Chris Hodges solved that problem a long time ago. CAPSULE.

thirdchildhood 11-12-2011 07:18 AM


Originally Posted by BROWNIE (Post 3548070)
When the boats finally got past 100, Cougar spent some time on the subject. Back then we had rules which kept engine HP down to a reasonable level, since we had to go a couple of hundred miles sometimes. We built a new 38' aluminum cat for Ted Toleman to break the "Ton" (100 mph). It was the first cat with the last bottom panel parallel with the datum line, which allowed the boat to "trim" by rotating on its center of balance. It was possible to raise the bow without raising the entire boat. Still didn't make 100. We built a 12' wide, 4' long slot/flap, end plate NACA 29 aluminum wing to mount above the CG. We ran the boat at its best performance, 98 mph, with a broom stick with lints taped to it, and discovered that the lowest level of 'clean air' was 7 feet above the deck. We mounted the wing there, and set the wing at 3 degrees plus angle, and the flap at 20 added degrees, down. According to the NACA book, that wing would provide 1260 pounds of drag, and 4,400 pounds of lift. We considered supplying oxygen to Smitty and Ted for the record run, since they might not be able to breathe at those speeds. It ran 99. Sonny Levi, who has an aero degree allowed as how the only benefit of the wing raising the drag center.

In my opinion (bear in mind that my earlier training was skipping flat rocks on the Wabash river), aerodynamics of a big fast cat 'in trouble' is more akin to ditching a plane than regaining any semblance of control, man, computer, automatic or whatever. Chris Hodges solved that problem a long time ago. CAPSULE.

There it is. From a boating legend. Great post.

PhantomChaos 11-12-2011 09:02 AM


Originally Posted by thirdchildhood (Post 3548109)
There it is. From a boating legend. Great post.

I agree. Great post. Thanks Brownie.


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