Thanks, Tom.
I have the uttermost respect for your fea simulations and your work with the UIM but I have to disagree with the material test.

The four point bending test is a common test for composites. It's cheap but that is the only good thing about it as far as I can see.

I 'm sorry but I don't like it at all. I don't think it's any good for safety applications (but very useful for other applications).
In the four point bending test you measure stiffness of the material. In a safety application stiffness is important but ultimate strength is much more important.
The four point bending test will promote material with high stiffness rather then strong materials.

IMHO the test need s to be redesigned to fit safety applications. A 10000N material isn't necessary stronger then a 3000N material. Just stiffer.

We believe an independently certified "race pod"
Is the true answer to the dilemma we face. All new race boats would be required to incorporate the design. Miss Geico has done the best we can with what we have and there is always room for improvement

So who will fund, build and certify the pod remains to be seen. We are certainly willing to play a part if the sanctioning bodies are willing to stand behind it.

A joint venture, with all the major players and the racing bodies, once the design is solidified, a prototype is built and pressure tested, the hard costs will be known and unit cost can be assigned.

I agree that there are lots of disadvantages to the four bar test. It can be scammed by creating a layup with a thick core and thin skins, and it will be stiffer. There is also judgement involved as to when the panel fails. A thin skin panel can be deemed to fail when the skin wrinkles for example.

Another test UIM uses is the test they use for penetration where a steel penetrator is dropped onto a square panel. This one isn't very applicable to Offshore and is expensive.

Dropping a complete pod onto a surface has the problem of the repeatability as well as expense.

I would like to get suggestions for a standard test that could be done that would be more applicable to the accidents we are seeing. Perhaps a couple of different tests.

I would hope the boat builder would be knowledgable enough to go for a good balance between stiffness and strength.

I would sure like to see the results of Gripenland's LS-DYNA project. That software is out of my price range. It would sure be an advancement in our knowledge.

By the way, I too am in favor of a standard pod that drops in, rather than a canopy.

Tom Stanley

It should be built in an autoclave from Prepreg, so Test the completed unit in the autoclave, very controlled and ramp the pressure up with probes checking movement also a safety factor.

the single pod is the way to go, just don't see having one lone manufacturer as plausible.

a better solution might be a design criteria that each individual boat builder can use. this way they can use their existing canopy molds. i just see disagreements over costs from builder to builder.

the flat panel tests are atleast a basis to start with. honestly i dont see anyone spending 50k plus for full size destructive testing. although this would be ideal, we're talking about a bunch if guys that can't even agree to run in one class.

Component testing is always a good start.

The pod would be designed to deflect/mitigate energy not to absorb energy. Therefore a full size pod test would only be destructive if the pod fails.

Acceptance and open sourcing the pod/canopy models via something like GNU/GPL could promote implementation consistency, facilitate collaboration, and integrity of the models during continual iteration.

CFD engineering simulation software will run your FAE design (rapid prototype) in every potential physics/environment permutation, yes it is expensive. High end CFD simulation software companies and third party labs offer a cloud solution where you don't need to buy the software and pay only for the analysis/results of the model. Like renting, very reasonably priced, provides objective analysis and data from a third party.

Clearly, software simulations objective is not to remove real world testing, it's purpose is for rapid prototype, discovery and evaluation. Allowing one to have the model (facts) of what is being produced and tested a/w/a facilitate the sharing of the model.

Rocket parachute, cool! That's some great out of the box thinking. Moreover, building on your concept a well designed transom released progressive torque drag line apparatus into the water could potentially correct aggressive x, y and z axis.

For the pod, the shape of pressure vessels is kinda well known and an egg shape was mentioned, the composite calculations can be done simply, now the canopy should be one piece (thick) making itself watertight as well, being trapped upside down in a leaking cockpit is not cool.

Any ideas on how to preform a real world test?

What type of accident would generate the most force on a cockpit?

Stuff?
Flip?
High speed roll?