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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)

DiamondPerformance 11-10-2011 08:04 AM

The only other big cat i can remember blowing over like Big Thunder is Cat Can Do in a Kilo Run back in the late 90"s.

TeamSaris 11-10-2011 08:19 AM


Originally Posted by GLH (Post 3546651)
You'll never perfect any vehicle (car, boat & plane) for all eventualities.

Go for a ride in a 1962 car with no headrest, no seatbelts, no airbags, no crumple zones and see how safe you feel. People still get wiped out in cars... Actually just ride a motorcycle...

Things evolve relating to protection with experience and technologies, sometimes expensive "feel good" legislation but I doubt we will cover all scenarios.

You summed it up perfectly.

Offshore Dreamer 11-10-2011 09:39 AM

These types of fin/ foil ideas had been in the back of my mind for a while, ( like everyone else, who hates reading the stories of these accidents)

While Im no aerodynamic engineer, and unfortnatley I have not mastered the CAD program, based on my remidial knowledge, I believe there are two computer controlled fin type systems With pressure sensors that could be developed.

Are there any resources or engineering firms willing to at the very least create a blueprint and CAD of these ideas?

Siide note, what/ When was the accident that mandated the hatch and oxygen systems?

Also, Perhaps a HANS device would be apllicable as well or a Leatt

Thanks, David

GLH 11-10-2011 09:53 AM


Originally Posted by DiamondPerformance (Post 3546660)
The only other big cat i can remember blowing over like Big Thunder is Cat Can Do in a Kilo Run back in the late 90"s.

The Victory Cat in december a year or two ago seems to have been in an accident/blow over very similar to this in the Middle East, with the same unfortunate results. There is cockpit video of that unfortunate accident.

I recall another I think with a 50 foot cat in Australia I think that went over crossing another boats rooster, that one landed upright and the guys where all set. There is outside and inside video of that.

kap328 11-10-2011 10:15 AM

Comment:

GLH your prior post was well said about no perfect scenario. The X-Cat series in Dubai, also had a boat kite over and both driver/throttleman were fine.

If you really want to address the safety issue then capsules would be the way to go. In drag boats no one would drive them without one. I have witnessed many horrific crashes with the driver walking away or having minor to moderate injuries. In drag boats you have speeds in excess of 150MPH on a frequent basis.

Capsules work and you do not have foils and the like to contend with. It is a static safety feature meaning it works as soon as your strapped in....from the first corner to the checkered flag.

I could see this feature incorporated into a big cat or even big v-bottom for that matter.

KAP

GLH 11-10-2011 10:17 AM


Originally Posted by Offshore Dreamer (Post 3546729)
These types of fin/ foil ideas had been in the back of my mind for a while, ( like everyone else, who hates reading the stories of these accidents)

While Im no aerodynamic engineer, and unfortnatley I have not mastered the CAD program, based on my remidial knowledge, I believe there are two computer controlled fin type systems With pressure sensors that could be developed.

Are there any resources or engineering firms willing to at the very least create a blueprint and CAD of these ideas?

Siide note, what/ When was the accident that mandated the hatch and oxygen systems?

Also, Perhaps a HANS device would be apllicable as well or a Leatt

Thanks, David

Another thing to remember also is that the more complex and expensive you make the basic equipment the less amount of boats you will see racing...

The number of racers are diminishing year after year at least in Key West already. (I'm sure the fact that they have to deal with that marketing major Carbonnel might be a big factor also... but let's not get off point!... That felt good!)

PARADOX 11-10-2011 10:18 AM


Originally Posted by BraceYourself (Post 3546646)
These cats at the speeds they're running are practically aircraft. I think the idea could easily be done. The weight and momentum is going forward. To change the pitch does not take much force. Look at airplane controll surfaces. Pretty small in comparison to the plane and can change all directions accept reverse in a split second. Computer controlled could work. The idea of a cat is to run level almost all the time. The wing could be constantly correcting for pictch. Just like an airplane does on auto pilot.
For instance... A wave smashes the bow up. Instantly the wing pushes it down but then can counter act if it senses it to be pushing the nose down to hard or "fast". Planes can change there pitch to go from a 1000fpm to 0fpm to capture an assigned altitude.
With todays WASS GPS and its (continuing to get better) the precision from the water could be there. Along with sensors to account for waves.
But like whats been said before... It takes money and this sport is to small to see the development come to life.

I agree & good points. I talked to several builders regarding this in the past few years. When you start talking about "packing air, etc" air dynamics as well as hydrodynamics comes into play. Some of the answers why it's not done to date, while the tech exists.:
As far as I know, the wing at the bow is not allowed in the race circuit. There is a cost to consider. Some of the big boys may have the $, many will not.
The same concept could be applied to tabs also. Software and a gyro, computer no biggie. The actual mechanics and speed of "wing" operation is the costly part. A stealth fighter would not able to fly with out computer control.
However. With added boat control, pitch, leveling etc. comes the attorney and insurance BS. Speeds may even escalate, and then a weekend boater have an accident and insurance co's, attorney would be all over the design.
Discussing this a few years ago with recent new boat builder they told me that the legal issues not worth the implementation.
Perhaps be in the race circuit above certain speeds/size, HP ? etc. should be allowed.

GLH 11-10-2011 10:27 AM


Originally Posted by kap328 (Post 3546756)
Comment:

GLH your prior post was well said about no perfect scenario. The X-Cat series in Dubai, also had a boat kite over and both driver/throttleman were fine.

If you really want to address the safety issue then capsules would be the way to go. In drag boats no one would drive them without one. I have witnessed many horrific crashes with the driver walking away or having minor to moderate injuries. In drag boats you have speeds in excess of 150MPH on a frequent basis.

Capsules work and you do not have foils and the like to contend with. It is a static safety feature meaning it works as soon as your strapped in....from the first corner to the checkered flag.

I could see this feature incorporated into a big cat or even big v-bottom for that matter.

KAP

Indeed your very right.

But all this lets not forget makes racing more and more expensive and out of reach of even more people than it is now...

You would entail needing new boats or serious mods to the boats currently racing.

Take out any boat racing in Key West older than three years or had not had a MAJOR refit and you will only have 5 boats left this weekend.. approximately.

kap328 11-10-2011 10:41 AM

Hello GLH:

The Unlimited Boats have Ron Jones building capsules for them and they are not a one time use item.

If you recall and I'm sure you do in the past all the offshore boats were open cockpit. Now mandated all boats to have full canopies.

The evolution of the offshore racing would also have a transition. This means that all new models would be required to have capsules especially in the 850 and above classes.

NOTE: This versus some nonsense computer controlled foil. The capsule works for all circumstances when the occupants are in trouble.... barrel roll, kiting, equipment failure.

The capsule could be a break away type which could be incorporated into an existing hull. The Drag guys destroy entire boats and engines and still would never dream about not having this feature.

As for costs let's face it the teams are not racing for money or purse.

The solution exists it is up to those that are involved to determine what levels of risk they are willing to accept and undertake.

KAP

iamjoe 11-10-2011 11:48 AM

You certainly don't have to go very far to see that a similar concept has been designed, perfected and has saved countless injuries and dollars.

Nascar adopted the roof-flap several years ago. While it is much more simple then what a device for a boat would need to be, it works every time.

I don't think Cats are designed to run the fastest when they are teetering on blowing over. The way I understand it is that a Cat will run the best if the tunnel provides lift to both ends of the boat. The bow will lift more because this is the point of entry for the air providing the lift. But, the aft is designed to lift as well, so the entire hull creates less drag and the speed increases. I think the trick is to control the aft lift so the props keep biting and the forward motion isn't disrupted.

On paper, it seems pretty simple, but in the real world there would have to be a lot of single components working together.

Regardless of how it happens, there has to be a particular angle of attack that is the point of no return, which is when the boat can't be saved. The trick is to design a device that senses both the angle of attack, wind velocity and the forward speed that can deploy and retract very quickly or slowly, depending on what condition it senses but ultimately deploy at a set angle less than the poit of no return.

For example, in yesterdays disaster, the device would sense that the boat had strong forward motion, a rapid change in wind-speed (assuming a gust of wind caused the blow-over) and reached the point of no return quickly. It would deploy quickly to aerodynamically place weight on the bow and bring it back down to earth, but would also have to retract fast enough so the boat doesn't stuff.

On the other hand, it would have to very particular as to when and how far it deploys. There was a post the other day about "hanging it way out" or something similar. That boat was certainly hung out there, and the last thing they needed was to be slammed nose-in to the wall of a swell.


Unfortunately, time and money is all it takes. I would think that a flap, hinged to thr rear/opening to the front, fairly large in size with the ability to sit flush with the surface of the tunnel, set with a series of very strong actuators that would be computer-controlled and hooked to quick sensing angle sensors, wind and speed sensors (and structurally supported) would do the trick. I don't know what you make the flap with (carbon fiber?) or where you get the actuators, but I'm sure that they can be had. As far as the computer, how hard could it be to program something so simple. As for the sensors, the aviation sector could provide those.

In my opinion, ALL of tha Cat manufacturers should put their heads and their money together and come up with something that will come as standard equipment. After all, with the kind money that the buying public who support these companies spends on these boats, it would be a gesture that would bring a ton of press and truckloads of goodwill (not to mention the creation of a most brilliant customer preservation program), it would pay off for them in the end.

Just think, a story about how a series of competitive businesses teamed up for the overall saftey of their customers? Forbes, Wallstreet, World-wide exposure for a "feel-good" story about competitors teaming up etc.

With disaster, sometimes comes opportunity! Maybe some of you guys that have the dough would like to enter into what could be a lucrative enterprise? I'm game for sure on this one!!!!

I wonder if theres an app for that?


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