glassdave

I think OL uses finite element analysis

Steve 1

Dave Thanks, My problem was I did not have my Dad (even at my age) for a counsel to get my mind right! And had to make that journey alone a long ways from home and family, But I spent a LOT of time A LOT on that very subject,(keeping a customer alive) Before I came back, I had a VERY cool project worked out for a Sheik, ready to go upon my return, But 9/11 put the whammy on it.

The Autoclaved stuff is a different world, Fascinating is an understatement (but just working in that tunnel is claustrophobic) and the new prepregs are amazing, I have always used a lot of Uni’s in my work and this fits right in. There is a big Clave in your neck of the woods I think.

40FlatDeck

If you did not know what you are looking at, you would think this was a road race accident. You really understand the violence of water, and what it can do at speed. I thought I remember hearing this boat was running around 100mph when this happened, forgive me if I am wrong about that. That is cruising speed, nothing near top end. These poor guys had no chance.
I guarantee this exact thing happened to Big Thunder, only the water had 2 cockpit hatches and 4 engine compartments to shoot through. What good is onboard air if the face mask get ripped off or you can't use if you are knocked out? If you think the guys were concious after water hydralics through, I have news for you.......

Really, the only way I can think of water not trying to come in, is making a cockpit without and escape hatch on top, drivers only entering through the bottom, but I know that is not feasible. I also think a big part of it is the engine compartments, and water blowing through the rear, or, aft bulkhead. I don't see many people talking about that. Is that not as much of a problem as I think it is?

I would love to get a round table discussion with Steve1, GlassDave, Jim(Freedom), and of course, T2x. If I were building a race boat, these are the guys who would build my cockpit structure.

God Bless those who we have lost........

Gripenland

There are many different materials and techniques to increase the material properties of the outer shell. Autoclaving is certainly one of them. Is there actually autoclaves that can do 1000 psi?

But material properties are only one half of the solution. The shape/thickness is the other. A thicker but weaker material can be just as strong as a high tech material. It will be heavier but usually cheaper.

If weight is the issue, one alternative is to autoclave other parts, putting the crew on a diet etc, etc.

Don't get me wrong. Autoclaving, zylon fibres etc are great but does the increase in cost justify the performance? Maybe it does, I don't know?

But drag boats and unlimited hydroplanes achieve good safety with low tech (but well engineered) materials.

There are many ways to skin a cat so I guess each designer and client needs to make their own compromises.


I'm using finite element crash software to simulate a cockpit crashing in to water. It is a work in progress but the possibilities are endless. It is very expensive though and I'm not sure it's feasible for a single boat manufacturer to spend that much cash?
It would be nice to see a joint venture between a group of manufacturers.


@40FlatDeck: According to the report they were going 125 mph before the flip and 109 mph at contact with water.

glassdave

40 the other thing btm had going against it is the open four many canopy with no bulkheads. Very bad idea in a race boat, far to many ways for that to fail. They calculated the Victory boat was going just over a hundred at the time they were upside down and coming back into the water. You are correct and i agree, i also believe a somewhat featureless canopy would help but the hatch would be the tricky part.

glassdave

I have seen drag boat capsules mentioned in this and other threads and i think it is important to note that the reason they have worked so well is in there ability to detach themselves from 90+% of the mass in the system. Only having to deal with with itself and its own energy is what allows them to stay together. When you move into a larger platform with greater masses it gets much more difficult to carry these concepts linearly. The instantaneous violence of a drag boat in a snap roll or a hydro many times affective catapults the driver/capsule out of the danger zone to skip along scrubbing off energy. I am sure there are elements that can be used but i am still thinking robust well engineered protection is the key.

I would love to see how your simulations go.

Gripenland

I'm very glad you mentioned this, glassdave. It's very important to get the physics behind a crash right.

1. A body's drag through water is not dependant on mass. Please look it up if you don't believe me. Drag will generate the forces on the shell.

2. Submersion (exposed drag area) is dependent of mass.

3. Deceleration is dependant on mass

4. The human body is highly affected by deceleration over certain levels.

I'll see if I can write some sort of an example...

glassdave

good point, i guess i am speaking of maybe more of a the multiple components. I dont think any drag boat crashes are submersion atleast not like we see. Detaching themselves relieves them of the ability and mass to submerge them i guess was what i was after in my head. Without the rest of that boat attached it lacks the mass to push itself through any high drag environment and will decelerate. I am sure you know more then me how delicate the balance is. Thanks

Gripenland

You are totally right! They skipp over the water and therefore submerging very little area. But if they his a wave in more offshore like conditions the accelerations would be extremely high since they have so little mass. That is enough to kill a man.

Steve 1

1000 PSI? Yes they go much higher; they have 200 foot length and 32 foot diameter with 8" steel thickness that are claimed to do 3000 PSI and 1500 F ,there are others claiming much more, I have had a piece if fighter jet control surface in my hands before, Impressive, when viewed through a magnifying glass.

I do not understand the reluctance here to rent clave time?

It is a sound investment for the huge return and pieces of mind, No short cuts everything done as well possible.

As for different the combinations of material, I have used about everything available at one time or another, especially back in the day trying to glean every gram out of the hull shell and internal structure in the race equipment.