The front of the car didn't held up to well! Can anyone explain?
I'm not a scientist, but shouldn't carbon fiber absorb more energy then that? I Hope Billy gets better!!!
https://www.youtube.com/watch?time_c...&v=ghz4HmIwJP8
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The front of the car didn't held up to well! Can anyone explain?
I'm not a scientist, but shouldn't carbon fiber absorb more energy then that? I Hope Billy gets better!!!
https://www.youtube.com/watch?time_c...&v=ghz4HmIwJP8
It was a very serious crash.
More discussion here: http://www.apexspeed.com/forums/show...ghlight=Monger
Fortunately there was a generous fundraising campaign and his spirits are good.
The energy that has to be dissipated goes up as the square of the speed - meaning that at 100 mph the tub has to withstand 4 times the forces that it would have seen at 50 mph. It's hard enough designing and making a vehicle that can withstand a 50mph crash without the tub being compromised, and damned near impossible for 100 mph.
Add to that this thought - to keep the g-loads the driver sees to levels below that which will kill him, you need crush space, and a car designed for 100 mph crashes would need double the crush distance ( assuming perfect crushing) of that of a 50 mph crash, and a bit more than 3 times the distance that the cars are designed for.
Further, testing is done against a nice wide and flat barrier, maximising the probability of the forces being dissipated through the structure correctly. Crashes into a gearbox are far from ideal.
Has a safety cell/ cage roll cage been designed and or tested? Just guessing, maybe the cage absorbing some energy and the tub takes the residual energy!Quote:
Originally Posted by R. Pare
Yes. The cars have been designed to perform to at least the levels required by the FIA.
As stated above the massive deformation of the tub could have saved his life. Obviously non of us know what's happened exactly but the damage to the tub was energy not fully tranmistted to the driver. Bear in mind the F1 nose crash test is performed at something like 30mph.
Chevy: That deformation of the tub showed the need for greater crush length with that speed - while it unfortunately allowed intrusion into the divers legs, it also kept the g-loads low enough to not instantly kill the driver. Even with that extra crush distance, he probably saw g-loads well over 100 g's, which, depending on the length of time he was subject to those forces, could have easily turned his whole body into a mass of jello.Quote:
Originally Posted by SEComposites
Quote:
Originally Posted by chevy 1011
Famous last words.
Perhaps an energy absorbing crash box on the gear box would help ?
That COULD help a bit, but only if the nose of the car hits it perfectly. Rear crush boxes are really for backing the car into a barrier.
I am not trying to start an argument here and I do understand everyone's logic. But I have noticed trends with racecars, especially with formula cars; sacrifice this for speed or this to save most of the car. Now, the car did absorb an ideal amount of energy. But looking at the video, the energy traveled instantly from the point of impact in a direct line to the drivers cockpit. Now I do understand it was a 100 mph crash. Take a look at this design for a car!Quote:
Originally Posted by SEComposites
Attachment 71149
I do think it's lacking in some areas, but would this help in this incident?
The cage taking residual energy and transferring it around the driver; combined with the carbon fiber! And the steering shaft causing further injury reminds me of Ayrton Senna's crash!!!
And I also agree, where the H-E Double hockey sticks were the yellow flags being a pro series! ( and from my experience and watching races PEOPLE DO NOT SLOW DOWN DURING A YELLOW FLAG!
If only there was some odd tech for exploding foam or some odd material!
Firstly Senna's injuries were not caused by the steering shaft.
The image you posted is a front engined GT or prototype car so bears little relevance to open wheel single seaters unless you want to re-define what a formula car is? A steel structure over the cockpit of a single seater wouldnt do much in this accident accept make driver extractions even harder.
As as mentioned earlier in this thread an FIA crash test is performed in controlled conditions and bears little resemblance to an actual accident. This is simply because there is no typical accident so you do need a baseline test which all cars need to pass. It's up to the rule makers to ensure that these tests are as relevant as possible to the real world.
We don't know how this F4 car performed in this nasty accident but I'd like to think the chasssis will be studied by the manufacture in case there are lessons to be learned. There are ways to help direct loads away from the driver but generally you need a bigger car to do that successfully. It's much harder in a narrow single seat tub.
Honestly Im not sure what what detrimental trends you are talking about with modern formula cars? F4 is the successor to Formula Ford in the U.K. In this case the 'trend' has been a move to carbon chassis and impact structures. Who here would rather be in a tube frame car in that particular accident?
Not slowing down under yellows is a problem but not relevant to this particular accident as the unfortunate series of events happened very quickly from what I've read.
Chevy:
If I am interpreting what you are saying correctly, you seem to believe that a steel tube structure around the driver (or over him) would somehow negate any intrusion into the cockpit area. Such is not the case, unless the kinetic energy left to dissipate has already been reduced to below that which would deform the steel tubes.
In any structure with a driver in it, the crush structure - if you want to eliminate any intrusion into the cockpit area - has to be fully contained outside of the cockpit area, and the amount of kinetic energy to be dissipated depends on the speed and the mass of the vehicle. The greater either is, the longer the crush area needs to be to keep the loads the diver sees below that which would kill him. Yes, a structure can indeed be provided that would stop a 1200 pound car at 100 mph in 15-20 inches, but the driver would probably be dead from the deceleration forces imposed on his body.
In talking with Lee Dykstra once about his time engineering the Ford Safety Car project ( late 70's, If I remember correctly), they gave up on it as being doable as a steel tube structure - tube structures are too unpredictable in how they deform. With modern street cars and a very complex sheet steel structure where the deformation is more easily controlled ( and can be predicted very nicely with FEA nowadays), they still are relying on crush distance and predictable deformation.
In this particular crash, the object against which the car hit - the other cars gearbox - was far from ideal in imparting the forces into the crush structure - think of slapping your hand against a flat table top verses slapping it against a pencil point. An extreme example, yes, but it should give you an idea of what happens when the loads are concentrated over a small area verses a big area. Look at the difference in cockpit intrusion in street car crash testing of full-contact frontal crashes against a barrier verses the front-corner impact test.
When I said senna's crash; I was relating to the a arm swinging around in the cockpit like you see in his crash video. And I'm not talking about reverting back to a tube frame; I am saying a hybrid frame in a sense, like in the above design minus some features in it. The cars would keep the same shape of course, just with some reinforcement that's all.Quote:
Originally Posted by SEComposites
This would explain allot. Just adding some input. Like I said, I'm no scientist!Quote:
Originally Posted by R. Pare
"You can't build a car with one person"
I don't believe it has much to do with there not being a typical accident, but rather they just need a baseline that all constructors feel is reasonable. They don't want to set a spec that only their competitor can meet. Same thing with SFI.Quote:
Originally Posted by SEComposites
When a big time racer dies in a fiery wreck people will realize just how piss poor our fire protection really is. It's just a matter of where we've determined that bar to be acceptable. Same thing with these crashes. Many folks, including me, are just ignorant of what type of structure(s) would be required to survive an incident such as this unscathed. We ignorantly and gullibly believe that the FIA or SFI is looking out for our best interest.
Isn't that exactly what I said?
Based on how I interpreted your post, not quite. I don't believe the reason(s) safety standards (FIA or SFI) are what they are has much to do with there not being a "typical accident" but rather they want to set the standards high enough to give the racer some sense (false or real) of safety, but yet low enough that the manufacturers are on board. The SFI for example, allows the manufacturer members to create the standards for the tests they are going to undergo.Quote:
Originally Posted by SEComposites
in crush structures, the SFI has nothing to do with them. The FIA and other standards have all be based on actual crash testing, with the requirements based on what the consulting engineers found was necessary for driver survival. Those standards and any mandatory construction techniques hav increased over the years as more and more real world information and materials have changed.
Quote:
Originally Posted by R. Pare
I was speaking to safety standards in general. But, to clarify, it would depend on what one considers a crush structure: SFI cage/tube padding is certainly a type of crush structure. All NHRA chassis for classes under a certain ET have to meet a SFI spec. Drag boat capsules have to meet a certain SFI spec as do the capsule class cages.Yes, standards have evolved, no argument there.However, those consulting engineers establishing the FIA standards are dictating what would be necessary for driver survival at deceleration rates that are well below real world potential....as in F1 front impact test is done at 33mph, rear at 25mph, and lateral at 22 mph with no more than 60g's to the analog 3ms after impact.
I still think exploding foam is a good idea! Thanks for the info guys.Quote:
Originally Posted by Daryl DeArman
http://www.grandprix.com/ns/ns36520.html
...at Monaco.....modifications to the jack-supports at the rear of the car.
- only a month after Billy Monger's accident