Side panels and other upgrades

[R. Pare]

A few people have inquired about adding side panels to their car for additional intrusion protection. Unfortunately, that other thread got locked just before I could respond.

Additional side panels attached on 6" or greater centers of various materials have been tried by different people many years ago and were rejected as being illegal, and the wording of the pertinent rules have not changed in the meantime.

Essentially, the current rules do not allow ANY additional add-on panels between the frame and the bodywork (regardless of method of fastening), nor any substitution of materials from those listed for the allowed methods, and the CoA ruling has upheld this opinion.

Because of that, even the suggested kevlar panels ty-wrapped in place would not be legal at this time - whether or not their use has been ignored is not relevant as to their legality.

We have suggested many times over many years that the side protection lower limits be raised, and even added a slight change to the wording in the rules proposal to at least allow BOTH methods to be used, but the proposal has been shelved by the CRB for the moment.

My suggestion is for the members to revisit this issue in a clear and concise manner as a group. Many possible methods are available to add side protection without adding anything to the chassis structural stiffness, IF that is desired in order to not obsolete the older cars. I hope by late spring to be able to set up and test a couple of such attachment methods (pendulum impact tests) to verify the soundness and viability as pertains to older designs.

Further, the rules can be rewritten so as to allow specific additional methods and materials, in which case it is up to the car owner whether or not to spend the time and money for such upgrades.

It's time for everyone to stop bitching and whining about what you cannot do and start working on revamping the rules so as to allow the long-overdue upgrades.

[Mike Foschi]

Richard, if your putting this up here for Jimmy, of JIMH3036 fame your wasting your time. The car that he bought from Burke had the best intrusion panels made by Kevin Klepher (spelling?) which, if I'm not mistaken, are the same panels that are used in the USF2000 series now, totally leagal and would prevent 99% of puctures that are seen in these cars. So... either Burke removed them before he sold the car or JIMH3036 is just fishing looking for the GOTCHA event of the year before time runs out.

Jimmy, for full disclosure, do you have involvement with the Radon Co. or put a deposit down on a car? Your extreme rantings on this site are a little frightening. I'm surprised that your from Easton, PA cause most people I know like this are from the New England area, everything northeast of NY.

[Peter Horvath]

Anti-intrusion side panels are permitted between the frame and the seat, correct?

[R. Pare]

You can draw your own conclusions about the legality of additional panels from this sentence in the final CoA document:

"The 2010 GCR 9.1.1.D.7.b. lists only two methods for cockpit intrusion protection."

With that sentence, they're stating exactly what has been stated buy us in the peanut gallery for years : If it isn't one of the two methods listed, it isn't legal.

Personally, if I were to add panels to the inside of the cockpit, the last thing I would claim they are for is intrusion protection.

All this fun stuff aside, the time is now ripe for getting the desired upgrades so that we all know what is and isn't legal.

[jimh3063]

Mike:
To address you acusations. As far as the side panels in Burkes car, it's not what I am used to. Have you ever owned any other xSR or any other high end Formula car. I have and the VD is pretty lame compared to my old Stohr, my Lola 9230 or the Dallara. I don't think it will ever be as good as the Dallara or the Lola because of the tub construction. I do think it can be as good as the Stohr though. As far as Burke's car being the best intrusion panels, the ones in there are a far from a Stohr. I'll be at Sebring for the winter nats. Come on by and look yourself.

I think you may something on the location thing. I live in Easton Mass. I have a hard time taking your slander about people from New England coming from a person from New York. I would appreciate you elaborating on the phrase " cause most people I know like this" I think your girth may be effecting the blood to your brain.

As far as being involved with Radon Co. Not at all.
As far as having a deposit. No once again. I will say if the car does well, I will.
I do have a Radon Front Plane kit on my VD.
I have met Nathan twice. Once at the Lime Rock Pro Race and once at his house.
I went to see the cars. I have been more outspoken than most because I was listening to people make comments and pass judgment about a car they had never actually seen. I thought that was insane. I would suggest that people go up there and take a peek. I would be a lot more willing to listen to someones comment on something they actually saw. Make any sense?

Richard, I welcome your thoughts. It's productive and at least acknowledges the shortcomings if the currents designs. I plan on calling Elan on monday. I would welcome any help in navigating the SCCA on this subject. I think most FC drivers would also welcome any other suggestions or ideas in this area. No one here is going to knock something that makes us safer.

Jimmy

[Wren]

I have been more outspoken than most because I was listening to people make comments and pass judgment about a car they had never actually seen. I thought that was insane. I would suggest that people go up there and take a peek. I would be a lot more willing to listen to someones comment on something they actually saw. Make any sense?

You do understand that there were pictures in that thread and that they were put up by Nathan? Does that somehow not count as seeing something?

As for side intrusion protection panels, you can put a lot more than the minimum amount of kevlar in your side bodywork, that is a great start.

[jimh3063]

Wren:
Sure they do. Maybe he should have posted more. Not for me to decide someone else's business strategy.

As far as the Kevlar, you're probably right. Maybe that end up being the path I take. I just don't' feel like there is anywhere near what I'm used to. Maybe it's just me and no one else cares. Who knows. I do like Richards idea of exploring it more. Maybe there is a solution out there we can all agree on.

Jimmy

[VehDyn]

It seems we may be drifting back to the old thread....

Richard,

Great idea. Toss something out there and lets word smith it. It would be great to add some panels in the interest of safety. At the end of the day, the vast majority of us need to go back to work on Monday and really would find it difficult to take the time off of life to recover.

[R. Pare]

Jim:

Everybody has always been free to increase the ply count of the allowed kevlar in their cockpit side panels. Some people may have already done so, but most probably haven't simply because they never read the GCR or haven't thought about it - some people still won't go purchase a H&N device in spite of all the publicity, so it is a bit tough getting them to think about a passive device that they don't ever look specifically at all the time. Most manufacturers will build to the minimum requirements simply to help keep the price of the car down.

From what I understand, the Elan panel is a 3/8" thick panel made from recycled plastic milk bottles. It apparently works quite nicely and is relatively inexpensive compared to kevlar. The unfortunate part if the thickness - on many cars it will be hard to incorporate without lots of body modifications, whereas adding another 4-6 plies of kevlar will be pretty straightforward.

What we don't have is real data on the influence that polyester or epoxy resin has on the anti-ballistic properties - there is plenty of anecdotal evidence that the impact is rather negative. Whether or not a method can be devised to lay it in loosely like in vests - no one knows at this time. My guess is that it may be possible, but damned difficult to do properly.

We've got the winter to look various methods over, as well as any other basic construction/design allowances everyone thinks are desirable.

[R. Pare]

It seems we may be drifting back to the old thread....

Only if people forget to keep their tongues in check.

I suggest that we go back and take a good look at the rules rewrite proposal first to see if we can all agree that most, if not all, of what is there is or isn't what the basic intent of the rules have been, even if badly worded to date (the existing manufacturers agree on 99.99% of it) so that we have a common point to start from, and then start looking at any desired changes.

Personally, I have no issue with an allowance for aluminum front bulkheads - they can indeed help on construction costs.

Allowances for additional side panels, of whatever for materials, is also acceptable, BUT, with pretty specific limits as to the methods of attachment.

There may be more that others can post - I've got some other ideas, but need to sort out the ramifications first before voicing them.

[Darrin Teeter]

Jim:
"What we don't have is real data on the influence that polyester or epoxy resin has on the anti-ballistic properties - there is plenty of anecdotal evidence that the impact is rather negative. Whether or not a method can be devised to lay it in loosely like in vests - no one knows at this time. My guess is that it may be possible, but damned difficult to do properly."

Richard,

You are correct that adding a matrix resin to Kevlar or other ballistic fabrics actually reduces ballistic performance, for a bullet. However, stopping a high velocity/low mass bullet and stopping a high mass/low velocity car (or portion of a car) requires totally different mechanisms.

In a bulletproof vest the relatively high specific stiffness of a ballistic fiber propagates a shock wave that distributes the relatively low total energy of a bullet over a broader area (for example, your entire chest instead of just a small bullet sized portion of it).
Adding resin restricts elongation and promotes fiber breakage, which reduces that shock wave effect.

Using that same technique to stop a low velocity/high mass object works about as well as a bulletproof vest stops a sledge hammer. The impact load must either be attenuated (by breaking or deforming) or it must be distributed over a larger area. To protect against a sledge hammer you want a hard, strong shell to distribute the load (think of a crash helmet).

The specific impulse, or deceleration of the hammer into your side would be a lot more comfortable with something that spreads that load over a larger time period, even converting some of that energy into another form, so an energy absorbing material would really help your chance of survival.

That's where the fracture and fiber pullout mechanism comes into play for a polymer matrix composite (Kevlar/epoxy or most any fiber) panel.
With literally several square miles of surface area in a small amount of composite material, they possess the ability to absorb significantly more energy than other materials. This is the main reason that even a simple composite panel is still better than metal.

It would be possible to create somewhat of a "webbing" of dry ballistic fabric. (By the way, Kevlar is a trademark of a para-aramid fiber and there are several different grades, some which are almost as stiff/strong as carbon fiber). However, you would have to attach it to the frame in a manner that would transmit the load into the chassis.
That would have the effect of stiffening the chassis (when the fibers are in tension only), much as cables would. Leaving the fibers "loose"
without any tension would require a huge amount of depth behind the panel (think of the space required between a trampoline and the ground).

I am very curious what alternative methods you might be considering for attachment that would not affect chassis stiffness. Attempting to use elastomeric bushings to partially limit the stiffness of a panel design (metal or composite) would be very difficult to accomplish, since that amount of energy would quickly tear out the larger hole associated with the bushing. I simply do not see how you can provide adequate impact protection without retaining the panel and affecting chassis stiffness in some way.

There is a large body of information and testing out there on this subject. I did a fair amount of research into the state of the art when building Formula 1 parts/aerospace parts, and my feeling is that even F1 methods could be improved. What you propose is a very interesting engineering challenge, and I'd like to contribute if I can.

Regards,
Darrin Teeter
Fiber Dynamics, Inc.

[HazelNut]

enough of this crap. It's the non stop BS bickering like this that is killing us and driving people away from racing.

I've had money in hand for months, that I've allocated to buying a new car, but the BS politics is making me think that the smartest move is to do something else to entertain myself.

I can't be the only one that is sick of all this ****!!!

[Darrin Teeter]

Richard,

I have been digging around in some of my documentation & found the F3 rules for the Euro series, which is spec, but it does contain the following:

15.4. Side protection structure
15.4.1. In order to give additional protection to the driver in the event of a side impact, a flat test panel of uniform construction, which is designed and constructed in order to represent a section of the survival cell sides, must pass a strength test. Details of the test procedure may be found in art. 15.4.2 and 14.4.3.0.
With the exception of local re-enforcement and/or inserts, the lateral parts of the survival cell must be manufactured to the same specification as a single panel which satisfies the requirements of art.
15.4.3. Parts to this tested specification must cover an area which:
Ø Begins at least 250 mm high at the front wheel centre line.
Ø Tapers at a linear rate to at least 350 mm high at the front of the cockpit opening and remain at this height to the rear of the survival cell Ø It’s no less than 100 mm above the reference plane between the front of the cockpit opening and the rear of the survival cell.
Any openings or cut outs in this area must be of a minimum size to allow access to mechanical components.
15.4.2. The test must be carried out in accordance with FIA Test Procedure 02/00 in the presence of FIA technical delegates and by using measuring equipment which has been calibrated by the FIA technical delegate.
15.4.3. The test panel must be 500 mm x 500 mm and will be tested by forcing a rigid truncated cone through the centre of the panel at a rate of 2mm (+/- 1 mm) per second until the displacement exceeds 150 mm.
During the first 100 mm of displacement the load must exceed 150 kN and the energy absorption must exceed 6000J. There must be no damage to the fixture or border before these requirements have been met.

I am in the process of setting up a load/displacement test rig on one of my hydraulic presses to do some nose cone & tail cone static crush tests. I may be able to set up a rudimentary version of this side impact test rig. It will by no means be "certified" but would give some good comparative data for materials/methods where data does not exist (& it is cheap). I do have some specific things I would like to test, but I am open to helping out if possible. I need to dig up the specs for the test fixture....

Darrin Teeter
Fiber Dynamics, Inc.

[carnut169]

How often are drivers being injured by intrusion? I know GR got a wishbone in his leg but his car did not have the "anti-intrustion" bar so.....

is this really a problem?

Or is the problem that someone might use "anti-intrusion" panels to actually just add stiffness? My next question is how much better would the car be? Seems like the most flex a VD sees is in the engine bay. Cockpit is pretty stiff already, no? Isn't it also true that completely stiff is not always faster?


Hazelnut- just get that car, and let's race. Lots of good deals right now.

[jimh3063]

Richard/Darren:
Both of you have far more knowledge on this subject than I. I just want to feel safe in my car. Look at the cockpit of a Stohr xSR. I'm sure that panel stiffens the chassis. There has to be a something with similiar protection that doesn't break the rules.

Jimmy

[Jnovak]

We have the "panels" being discussed in our FE car. Even though it is not an FC car the FE car is a spec car & they are not "legal". However we like to call them interior seat panels. Once in impound with several other FE cars also with the panels installed, the chief of tech wanted to know what they were. After some dicussion they were determined to be "seat panels"

I cannot envision that ANYONE IN THEIR RIGHT MIND would protest this as a competitor or have a tech inspector do a "request for action"

IMHO the panels serve the same purpose in FC. Put your "seat panels" in your car & stop worrying about this ***t.

Let's get some common sense here.

Thanks ... Jay Novak

[Mike Foschi]

I think you may something on the location thing. I live in Easton Mass. I have a hard time taking your slander about people from New England coming from a person from New York. I would appreciate you elaborating on the phrase " cause most people I know like this" I think your girth may be effecting the blood to your brain.


Jimmy

Wow! You're right, the location thing is uncanny. I guess the " cause most people I know like this" means that they are all very smart, caring, considerate, giving, humble, and most of all good looking. While all we have in NY is sarcasm.
You're also correct about the girth thing and the blood to my brain, when I'm fully aroused I get dizzy. My doctor told me if I were to take Viagra it would cause so many brain cells to die that I would only fit in to soceity if I lived in the New England area, who knew?

[dc]

Ok, no more warnings to ANYONE about personal attacks. I'm done with it. Next comment that is even remotely insulting to someone else here and you are DONE on ApexSpeed.


ENOUGH!

[Mike Foschi]

Thanks Doug,
Can you believe that guy, he sort of hurt my feeling there saying I was chunky.

[Hardingfv32]

Could the seat be a complex molding that went from the dash bulkhead to the roll-bar bulkhead, and from the top of one side of the cockpit opening around to the top of the other? Are there restrictions to how a seat is mounted?

Brian

[cooleyjb]

Could the seat be a complex molding that went from the dash bulkhead to the roll-bar bulkhead, and from the top of one side of the cockpit opening around to the top of the other? Are there restrictions to how a seat is mounted?

Brian

Interesting thought as the cf NASCAR seats look a lot like the carbon 'tub' of a stohr wf1.

[R. Pare]

Richard,

You are correct that adding a matrix resin to Kevlar or other ballistic fabrics actually reduces ballistic performance, for a bullet. However, stopping a high velocity/low mass bullet and stopping a high mass/low velocity car (or portion of a car) requires totally different mechanisms.

In a bulletproof vest the relatively high specific stiffness of a ballistic fiber propagates a shock wave that distributes the relatively low total energy of a bullet over a broader area (for example, your entire chest instead of just a small bullet sized portion of it).
Adding resin restricts elongation and promotes fiber breakage, which reduces that shock wave effect.

Using that same technique to stop a low velocity/high mass object works about as well as a bulletproof vest stops a sledge hammer. The impact load must either be attenuated (by breaking or deforming) or it must be distributed over a larger area. To protect against a sledge hammer you want a hard, strong shell to distribute the load (think of a crash helmet).

The specific impulse, or deceleration of the hammer into your side would be a lot more comfortable with something that spreads that load over a larger time period, even converting some of that energy into another form, so an energy absorbing material would really help your chance of survival.

i agree with you on this. However, I think the main concern for most people is in penetration of small diameter objects, such as the axle shaft that penetrated the side panel of Dave Weitzenhofs car a few years ago and was only prevented from penetrating his hip by the vertical steel tube located there. I would place this sort of impact (and I'm admittedly no expert on this!) as being somewhere in between the bullet type ballistic scenario and the sledge hammer you spoke of.

In that sort of case, I would think that the ability to spread the load as well as be strong enough to prevent penetration is what we would want to look at. Since non-resin-impregnated material would not be the answer (because of anchoring and depth issues) it leaves us to sort through the various resin-impregnated possibilities to get the one that has both decent resistance to the sledgehammer, but also gives us the least one-strand-at-a-time localized tearing that a too-stiff resin would probably give.

Have you come across such information? My own experience in this so far is only with polyester resin and epoxy (West Systems) resins, and there are a ton of other resin types out there that might be better for this purpose.

Or is the problem that someone might use "anti-intrusion" panels to actually just add stiffness? My next question is how much better would the car be? Seems like the most flex a VD sees is in the engine bay. Cockpit is pretty stiff already, no? Isn't it also true that completely stiff is not always faster?

All other things being equal, a stiffer chassis allows better fine tuning, which in turn will make the car faster.

Jim:

The Stohr panels are not only riveted (bolted?) to the tubes, but I believe bonded as well, since there is no rule in DSR about the frame/chassis being tube only.

Until the rules get changed in FF and FC, we are stuck with just the 2 methods allowed. In your case, the method used is kevlar in the body. You can relatively easily add another 4-6 layers to you body, which would effectively triple or quadruple the penetration resistance.

[R. Pare]

Could the seat be a complex molding that went from the dash bulkhead to the roll-bar bulkhead, and from the top of one side of the cockpit opening around to the top of the other? Are there restrictions to how a seat is mounted?

Brian

Yes, you could, and it would be an effective means of providing a final barrier to penetration - it wouldn't prevent blunt-object trauma, but that's a heck of a lot better than having the body penetrated.

In any case, the seat needs to have its back properly supported (or be properly designed) so at to prevent buckling into a hollow behind it in a rearwards crash - ask Craig Taylor about that scenario sometime.

As to mounting, someone could try to shape and mount it in such a way as to add substantial stiffness to the frame, but the restriction would be whether or not it added substantially to the frame stiffness - yes, a rather subjective term (and I have no good advice on this at this moment), but something that needs to be kept in check somehow in order to avoid the sort of performance and cost escalation that can quickly kill a class.

[Dennis McCarthy]

Richard regardless of the material being used, would you agree that the outside of the tubular steel frame is probably the most effective place to attach an anti-intrusion panel?

[R. Pare]

Yes. because the panel then also utilizes the tubes to help keep down the distance the panel will intrude into the cockpit (for the "sledge hammer" type impact) - the load will be additionally spread over the frame structure. As to penetration by a pointed object, that will most likely be determined by the absolute strength of the material (along with its "ductility" of course).

Panels on the inside of the frame cannot utilize the frame as part of the load spreading to as great a degree as an exterior panel, since that would be determined primarily by the strength of the fastening system.

Interior panels do have an additional benefit in that they smooth out the cockpit interior, preventing point contact against the small surface area that tubes have. This can indeed prevent a lot of blunt force trauma to the body in a crash, and are well worth adding to any car whenever allowed by the rules.

[Dennis McCarthy]

So what you are saying is that a combination of interior and exterior panels would provide for the safest car?

[R. Pare]

Yes, but as always, it has to be done correctly to get the potential benefits.

[Darrin Teeter]

In that sort of case, I would think that the ability to spread the load as well as be strong enough to prevent penetration is what we would want to look at. Since non-resin-impregnated material would not be the answer (because of anchoring and depth issues) it leaves us to sort through the various resin-impregnated possibilities to get the one that has both decent resistance to the sledgehammer, but also gives us the least one-strand-at-a-time localized tearing that a too-stiff resin would probably give.

Have you come across such information? My own experience in this so far is only with polyester resin and epoxy (West Systems) resins, and there are a ton of other resin types out there that might be better for this purpose.

In a crash, destruction of the composite through fiber pullout, fiber breakage and resin fracture absorbs a tremendous amount of energy. Once the resin matrix is "broken" a good ballistic fiber continues to stretch and prevent penetration. A decent structural epoxy (West Systems or others) should do the job just fine and nearly anyone can make good parts in their garage. We use the resin transfer molding process (dry fiber with resin infused into it). We have one resin system that we use a lot in wings and unmanned vehicles that has nearly the fracture toughness of high impact polycarbonate (think safety glasses) and is great for damage tolerance, but may not absorb much crash energy. A typical epoxy laminating resin is probably a decent solution. Beyond that, you likely have diminishing returns.

One material that the FIA, Formula 1 teams and others are excited about is Innegra polyethylene fiber (www.innegrity.com). It is made in the USA and is cheap. It is a weak fiber, but when coupled with carbon, aramid, or glass really improves penetration resistance. I have attached an FIA paper on this, but it is aimed more at debris reduction & does not show how it is used in side impact applications. We used that material with a very low cost carbon fiber to make very inexpensive panels for the.....dare I say it.....Radon chassis. The idea was to provide increased safety while at the same time reducing cost, but the subjective issue of chassis stiffening got in the way.

The crux of the matter is still figuring out how to add protection without stiffening the chassis "in any way." I think that's going to be difficult, given the laws of nature, and it also prevents combining the benefits of a substantial tube frame with any sort of modern materials.

Also, correct me if I'm wrong, but aluminum panels are allowed to be mounted to the outside of the tube frame on six inch centers, aren't they? That would actually provide more chassis stiffening than a Radon-like panel. People tend to assume that adding carbon fiber to a car will magically make it infinitely stiff, but the reality is quite different. If you lay up carbon fiber in a way that provides equal strength in all directions (quasi-isotropic) then it's actually less stiff than aluminum. It's just a lot stronger and absorbs much more energy. Hopefully we can all find a reasonable way to improve the sport (safety & cost) while keeping the playing field fair.

Darrin Teeter
Fiber Dynamics, Inc.

[Darrin Teeter]

So what you are saying is that a combination of interior and exterior panels would provide for the safest car?

Disclaimer: I am not trying to stir up things by mentioning the Radon chassis, nor am I questioning the decision of the Court of Appeals. It just happens to be a project in which I was intimately involved where some very talented engineers thought carefully about how they could dramatically improve safety while keeping cost under control. The final panel design was the result of hundreds of hours of design and analysis, so rather than let that go to waste, I thought I'd share the lessons learned.

When designing the Radon, we looked at a lot of configurations. We actually started with an interior-only panel. That would have helped to distribute load, which may be useful for minor impacts (small, sharp objects), but the panel gets shoved into the driver in larger impacts and may create more problems than it solves. It should be securely fastened to prevent this, but that runs afoul of the stiffness "requirement." Most crashes do not happen exactly like an FIA crash test, so consideration of what happens in real life (or death) crashes is imperative.

Adding an exterior panel improves impact resistance by reacting against the chassis, but that is one more part to design, tool and fabricate. That adds a lot of cost and complexity. According to some, you then have to figure out how to attach the panel without adding to the stiffness of the chassis. Hopefully Richard or others can come up with a cost effective way of doing this.

Even if they do, it may not be widely adopted. Racers are very reluctant to add cost and weight to their cars in the name of safety. Despite the proven benefits, there are still many drivers in club racing who don't wear a H&N restraint. If improved anti-intrusion panels just make your car cost and weigh more, few people are likely to choose them, at least until forced to do so by the rules.

The solution for the Radon chassis was to produce a single panel that performed anti-intrusion / impact functions, while providing a smooth cockpit interior panel. It served to mount the shift linkage, ARB adjuster, bodywork, head surround, etc, etc, all functions that would normally require a bunch of welded or fabricated brackets. It also made the complete chassis, including the panels, cost less than a conventional tube frame. And it looks cool. In sum, you get all the benefits of improved safety while actually reducing cost. By fastening the panel (which is less stiff than a comparable aluminum panel) at centers greater than 6 inches, many SCCA rules-makers, and the first court, agreed that the concept was legal. Apparently the final COA disagreed .

Since that is now the law, the question is how to move forward with a cost-effective, safe solution for FF/FC cars? The simplest (thus cheapest) design is to make one part fulfill as many functions as possible. How do we attach a single panel to the chassis without running afoul of the "intent" of the rules? Any suggestions anyone?

Richard, thank you for starting this constructive dialogue!

Doug, thank you for keeping it constructive!

Darrin Teeter
Fiber Dynamics, Inc.

[Wren]

I know there have been some pretty nasty side impacts lately, but how many of them actually resulted in a serious injury?

[Darrin Teeter]

I know there have been some pretty nasty side impacts lately, but how many of them actually resulted in a serious injury?

I am not aware of any myself, but I am really pretty new to the sport. I hear a lot of people who have survived some pretty nasty shunts. The thing that replays most in my mind is the video of my son going through the bus stop at Watkins Glen at 110 & having a car back across the track directly in front of him. As I watch him take the wall option, avoiding a t-bone of the other car by inches, I wonder what would have happened if he would have been .03 seconds slower. He would have had no place to go. The accident would have almost certainly killed the other driver & would have probably left my son with a minimum of broken legs. The VD brazed tubing & puny nose would have not met up very well I imagine.

That thought has driven me to make every practical effort to make a car as safe as possible.

[Jnovak]

I think that the simple solution that would probably fit within the current rules is to design a "seat & interior closure system" that is bolted to the chassis in an adequate number of places. Obviously care must be taken with materials & the design. Adequate stiffness of the "seat" would make it a great intrusion & side impact device.

This may also be a way towards a design fix that would allow the Radon to fit within the current rule set without too many mods to the chassis. I do imagine that some triangulation of the open bays may be necessary but as I have done zero analysis of this concept I am making a guess.

Thanks ... Jay Novak

[Josh Pitt]

I know there have been some pretty nasty side impacts lately, but how many of them actually resulted in a serious injury?

this is something that happened in my DB-1

http://www.apexspeed.com/forums/showthread.php?t=26135

the link is to the thread, and pictures of the car, and my hip.
had this impact been just a fraction lower, my pelvis would have been in a world of hurt.
the incident occoured in a group that has no tech, and does not monitor what type of equipment is used on the cars, crush structures, or in this case the rear of a FV. SCCA mandates a verticle bar on the rear of the FV ( and the cage mandated by SCCA to protect the shifter) so that the rear of the car will not penetrate into another cars' chassis. the car that went through my car just had what i would call the equivalent of a spear with a blunt tip.

my input is on FF, but i think the FF and FC cars are the same.
I was not seriously hurt, thankfully, but i do feel that i was fortunate not to have been seriously injured.

IMO, ANY side impact improvement is better than what is currently used; i believe that i did have kevlar inside the body panels on the DB-1, and it didnt do jack**** to protect me.
Josh

[Darrin Teeter]

Well, I guess I'm on a roll. Sorry for all my ramblings, but I have lots of questions.

In addition to coming up with a side panel, or other, solution for anti-intrusion, what about impact attenuation (energy absorption)? I am not sure, but I believe the Euro FC/FF rules require higher/deeper sidepods. I have not found those rules. I also understand that they are in the process of adding FIA side impact certification to the FF rules. Is that true? If so, what construction solutions are they implementing?


Given the current interpretation of the rules to effectively ban any additional anti-intrusion safety features, is the addition of impact attenuation devices in the sidepod, or elsewhere also illegal?

[Dennis McCarthy]

I'm curious can someone shed some light on the reason for not stiffening chassis with panels in the first place?

[S Lathrop]

I'm curious can someone shed some light on the reason for not stiffening chassis with panels in the first place?

Yes.

The rules that made a distinction between tube frame and monocoque chassis go back to 1969 and the Zink and the Bobsy FVs. The Zink FVs originally had a very simple tube frame. The belly pan was 20 guage galvanized steel sheet that was riveted to the bottom frame rails ( 1" x 1" steel tubing). The belly pan was then wraped around the sides of the frame and riveted to the top frame rails. The pan, and now body side pane, was also riveted to the sides of the frame as well. The front and rear bulkheads of the frame also formed the bulkheads for the side monocoque boxes.

That was OK for several years until Jerry Mong did the same thing but added inner panels to the structure of his Beech FV. Now you had a tube frame that was completely boxed in to form a monocoque chassis. A pure monocoque tub would have done away with the tube frame and just formed the separate panels to rivet to each other. Someone even went so far as to fill the void between the inner panels and the outer panels with foam.

The rules were rewritten for the frame and both cars were deemed illegal. All the Zink FV frames had to be replaced over the next few years and the Bobsy just died.

This ruling is the origin of the 1" deviation rule as well but in FV it is lateral. When the English did the rules for FF they made the deviation longtudinal because of an issue with a car over there. I think the 1" inch rule was for cars like the Cadwell D13 that had lower frame rails that were round tubes.

Good, bad or indifferent, the Radon is a victim of the same rule philosophy that got the Bobsy and the Zink. The Radon did nothing different than the Bobsy.

There is a principal that is implied by the tube frame requirement for classes that are required to have tube frames. The structure that connects the front suspension to the rear suspension and supports all the other major components of the car will be a tube frame construction with very limited concessions to other construction techniques. Interwoven in this design restriction is the safety requirements for the roll cage.

[Dennis McCarthy]

I understand monocoque construction having worked on various Ralt & March FAs and FSVees back in the early eighties. That being said, if a tube frame is retained within panels why not? Cost containment? If that were the case why was data and modern shocks allowed in? It would be much cheaper to skin a tube frame than to buy a set of triple Penskes.

[HazelNut]

quickly kill a class.

you know what else kills a class? incessant squabbling over BS.

Building the cars might border on rocket science, but driving doesn't. It's just club racers driving around in circles attempting to entertain themselves, because golf is boring.

[DanW]

It's just club racers driving around in circles attempting to entertain themselves, because golf is boring.

Amen.

On edit, I think most of us would like to see a rule that will help the manufacturers build a safer driver capsule, and allow those of us with older cars a means or guidance to retrofit a useful improvement without adding too much weight.

Agree about increased stiffness making fine tuning easier. It appears to a layman like me the lack of stiffness in a modern tube fame car is mostly between the firewall and the rear suspension pickups, not the roll hoop forward.

Unfortunately, most of my limited knowledge is intutive or anecdotal. I observed a very good FF driver spend over a year getting rid of a miserable push that he finally solved by additional bracing back to the gearbox.

Regards,
Dan

[S Lathrop]

I understand monocoque construction having worked on various Ralt & March FAs and FSVees back in the early eighties. That being said, if a tube frame is retained within panels why not? Cost containment? If that were the case why was data and modern shocks allowed in? It would be much cheaper to skin a tube frame than to buy a set of triple Penskes.

Then you know the amount of work it took to maintain those cars. The top FA teams would change out the tub at least once a season and re-glue and re-rivet the old tub. Look at the trouble we have keeping the belly pans on tube frame cars.

Not only does the performance of the car deteriorate as the joints fail but the safety also suffers. The area where the degradation is worst is also the area under the main roll hoop.

The problem is that the tube frame is quite elastic (springy) and the panels that you are attaching are very inelastic. Thus the joints are always under stress. You fix the problem by adding more panels and stronger joints until the panels are the primary structure. Then it is no longer a tube frame. But the rules require tube frames.

One idea for attaching safety panels to a tube frame structure that is being discussed or implemented in Europe is to have the panels bolted at the 4 corners only. Additional mounting is provided by "u" bolts or clamps in the middle of the tubes of the frame behind the panel. This allows the frame to flex as it does its job but keeps the panels in place to protect the driver. The fastening system retains its integrity over time.