Woooo Hoooo! Let's go break something!!

[gsbaker]

Now really, next to your favorite activity of racing, what would you most like to do in your free time? A little gardening, perhaps? Bird watching, maybe? Oh, oh, I know! Knitting.

Get real. Any racer worth his salt knows that in those moments of solitude, when his life resembles the cover art of Rod Stewart's "Never a Dull Moment" (ya there DB?), what he really wants to do is blow something up. Yup, admit it. If you can't hear the sound of the crank bumping up against the rev limiter, smell the brakes getting cooked or feel the ABS kicking in, you would love to experience the soothing, all-enveloping sound and feel of a good explosion.

Well, too bad, we can't offer that.

However, there is an excellent substitute which is not only non-destructive and politically correct, it can be scientifically justified. How good is that, eh? It is called a (Dr. Evil air quotes, please) "crash test". So, just for the heck of it, how about a crash party.

We could use the 50G sled at Wayne State, the 70G sled at Delphi or the 100G sled at MGA. (We could also use one of the European sleds, but why make the trek.) We could test anything or nothing, it's up to you. We could make it casual and just for grins, or we could go semi-formal and present it to the SAE for publication. We could keep it within IT.com or spread the word to other racers.

So, given all the safety issues involved in racing today, if you could have your own crash test, what would it be?

[ddewhurst]

***So, given all the safety issues involved in racing today, if you could have your own crash test, what would it be?***

Lateral test each H & N restraint system at 100G with a normal race seat, no lateral head support built in seat, no side nets or other H&N lateral support systems. :birra: :birra: :birra:

I would believe these videos would make one hell of a tool to re-kick your sales effort showing what some H & N restraints do not do. I would believe the videos would also kick off a real thought process for the SCCA CRB & BoD.

I was at the Farm this weekend for a National race & put a HANS on just to see. My first comment to the owner was that the HANS offers minimal lateral support as compared to the Isaac. The owners words, thoughts were a shrug of the shoulders. The owner is a pretty bright young man with many accomplishments in WKA Karting, SCCA Pro Spec Miata & SCCA FC. Monkey see, monkey do. I really don't believe many people who purchase H & N restraint research the details. They buy because the HANS is IRL, Champ car, NASCAR, F1 mandatory.

As a marketing consultant my fee is quite reasonable. One Isaac to go please & it will match my cap.

[Dave Burchfield]

Gregg,

Ummm.............lemmie see........how 'bout we crash the 009 Aston Martin like they did this weekend? Only rather than launch it backwards at turn 7 for a reported flight of 147 feet into China Beach, we crash it into something really good like the 30 degree offset at Delphi? I'll be there!!!! ..........or maybe we could crash some narrow minds into a concrete wall late one evening......... I could go on, but I am afraid it would go downhill from here........

[MMiskoe]

How about a pair of 2800 pound cars going nose to driver side door?

Or same car landing on its roof?

LF wheel intrusion into the footwell?

I've often wondered what the weakest point of the type of roll cages that we use would be. The mounts? Would it deform to the point of crushing the driver? Would the tubing rip apart at the welds?

Pretty morbid thoughts.

[924Guy]

Ah, if only the sled could do a multiple-impact test... throw a couple of obliques or the like at some H+N restraints... :cavallo:

[Despr8dave]

I think we should take a class A motorhome and drop it from a crane on it&#39;s nose, from say a height of 4 feet. Yes, only 4 feet. This should scare the hell out of anybody driving one of these potential bombs. Oh, wait a minute, I sell these for a living. ......Hey, what the hell, RV really does stand for "rolling volcano". Of course, the federal government may get involved and actually create laws for safety items on RV&#39;s. Will only save lives and cost $$$$$$$$$$!! <_< Lots of money.

[Knestis]

As a die-hard fan, I keep hearing the theme from Mythbusters as I read this. The quote a couple of weeks ago was, "If it&#39;s worth doing, it&#39;s worth overdoing" - right before they blew Buster up with a pair of explosive pants, I think...

The lateral impact is a good suggestion but it would be cool to see it looking at a number of permutations, combining parts into systems. It&#39;s been suggested that "wing" seats without off-side nets might actually be less safe in some offset situations, than would be non-wing seats, for example.

K

[gsbaker]

Since this thread was initiated solely for the purpose of amusement, my personal favorite thus far is Dave&#39;s idea of dropping the motorhome on it&#39;s nose. If he can find one headed to the scrap heap we might be off and running--well, certainly "off". :)

One of Dave B&#39;s offerings conjurs up pleasant images also. ;)

However, you guys may have stumbled onto something. Hmm. Let us do some checking...

[jamsilvia]

***So, given all the safety issues involved in racing today, if you could have your own crash test, what would it be?***

Lateral test each H & N restraint system at 100G with a normal race seat, no lateral head support built in seat, no side nets or other H&N lateral support systems. :birra: :birra: :birra:

I would believe these videos would make one hell of a tool to re-kick your sales effort showing what some H & N restraints do not do. I would believe the videos would also kick off a real thought process for the SCCA CRB & BoD.

I was at the Farm this weekend for a National race & put a HANS on just to see. My first comment to the owner was that the HANS offers minimal lateral support as compared to the Isaac. The owners words, thoughts were a shrug of the shoulders. The owner is a pretty bright young man with many accomplishments in WKA Karting, SCCA Pro Spec Miata & SCCA FC. Monkey see, monkey do. I really don&#39;t believe many people who purchase H & N restraint research the details. They buy because the HANS is IRL, Champ car, NASCAR, F1 mandatory.

As a marketing consultant my fee is quite reasonable. One Isaac to go please & it will match my cap.
[/b]

I would love to see lateral side tests - both with and without HANS/R3/Issac. When I was shopping, I looked around for some concrete data for all of the systems. There&#39;s just not a lot of good non-marketing type data there. This could be a chance to get some 3rd party data that wouldn&#39;t be given out with whatever spin the advertisers want it.

Dropping an RV on it&#39;s nose, though.....that would be damn cool! (scary, but cool)

joe

[gsbaker]

Geez, I try to have a little fun and within eight posts you guys turn it into work. Gosh, thanks! ;)

Back soon.

[gsbaker]

You guys are geniuses. Seriously, you have just come up with a great idea for getting around a huge problem inherent with lateral testing. I&#39;m jammed for time now and need to confirm something, but I&#39;ll try to get back with more details later.

Someone should revoke my engineering license for not having thought of this.

[benracin]

We&#39;re going to need to cranes for this one, but take the motorhome dropping on it&#39;s nose, now add a second motorhome above that one and give it a good following gap. This will help test the RV train crash. The first guy tried to stop but the second guy was too busy watching his big screen tv to see the first guy.

DOUBLE BLAM!!!! :035:

Oh, and then blow the whole thing sky high like they did to that cement mixer on myth busters.

[lateapex911]

Having just crafted my letter requesting a stay of execution for the 1/1/07 Head and neck restraints must be SFI certified requirement, I ,ight be a bit grumpy.

So I would request that whatever test you do, meets the stupid SFI requirements.


Or put the entire organization on the sled and test them...sans anything for protection. And maybe toss on an SCCA lawyer type or two, just so they can feel what it will be like after I hit something having been required to take my Isaac off.

Lawyers: 1
Common sense: 0

and another loss for personal responsibilty on the slipperly slope ........

[gsbaker]

Relax Jake, we&#39;re pedaling as fast as we can.

Hey, it might be a good idea to have the BoD at the tests.

[gsbaker]

As is obvious from the replys, there is significant interest in lateral testing of head and neck restraints. This is a serious issue that has not been adequately researched, IMHO. Within the past six months we conducted some testing that addressed this question, among others, but it has not been published. Personally, I&#39;d prefer dropping an RV on its nose to see if the microwave dislodges, but that&#39;s just me.

We have always wanted to conduct a complete lateral impact test series but there are problems desiging a valid test on the big-hit sleds. For one thing, the Hybrid III dummy is designed for frontal impacts and is not instrumented to measure side body loads, plus the arms and shoulders on the impact side tend to get damaged. For lateral testing you need a SID dummy. Unfortunately, these do not have arms, which raises questions about the validity of the results. Also, lateral testing tends to blow up seats like there is no tomorrow. This is why some people like to perform lateral testing--or any testing with a lateral component--using bench seats. We appreciate that that keeps things simple, but who races with a bench seat?

I love Dave D&#39;s idea of smacking the living snot out of everything at 100Gs. Unfortunately, we&#39;d be picking up pieces for a week after each test and someone is going to have to pay for a lot of seats and dummies. (A fully instrumented dummy runs about $100K; replacing the upper neck load cell is about $10K.)

For all the above reasons no one has performed comparative testing of H&N restraints in pure lateral impacts on high G sleds. There have been tests of side nets, but nothing that tests H&N restraints alone. Doing so is difficult and the results are questionable given the need for a dummy with no arms. Great idea; too bad we can&#39;t do it. The closest anyone has ever come is our recent work which isolated the lateral head torque in the 30 degree offset SFI test at Delphi.

Kirk&#39;s suggestion of considering the various combinations of H&N restraints, seats and nets brings into the equation the valid question of degree, i.e. at what level of G load do you need a side net, head surround seats, etc? Food for thought.

So, step back, take a deap breath and think about this for a minute. If you want to know how well a head and neck restraint works in side impacts, what do you want to measure? You want to measure head loads compared to a driver who has no protection. If you do this for all products, you have an idea of how well each product works. Simple.

But if that&#39;s the objective, why smash everything at 5 billion Gs just to produce sub-atomic particles and learn nothing? Why not put a real dummy, with arms, into a real racing seat and crash it on a real sled in a pure lateral impact and measure the head loads without blowing everything up? If we want to know about relative performance, why be concerned about absolute impact? Why not dial down the impact enough to keep all the pieces together? Hit everything at a lower G and still determine the relative performance.

We&#39;ve been working the phones. Both Wayne State Bioengineering Center and the Delphi lab are good to go.

[lateapex911]

Cool, I knew you were up to something, as usual.

But, if you go lower impact loads, will the results translate up the scale? In other words, how can you predict the linearity? Some designs would, I imagine, not react in a linear fashion. Perhaps a set of three hits, at different lower levels, just shy of the &#39;damage stuff&#39; point, to try and get some points that could be extrapolated from?

[gsbaker]

But, if you go lower impact loads, will the results translate up the scale? In other words, how can you predict the linearity? Some designs would, I imagine, not react in a linear fashion. Perhaps a set of three hits, at different lower levels, just shy of the &#39;damage stuff&#39; point, to try and get some points that could be extrapolated from?
[/b]
An excellent point, sir.

Testing has shown that head loads are not a linear function of impact, but it&#39;s close enough that proportionality is used frequently as a rule of thumb for estimating absolute levels. For comparative purposes it&#39;s a non-issue, i.e. if a product has a certain head load reduction at 50Gs, say, it&#39;s reasonable to see the same general level of performance at different impacts.

There is plenty of precedent. At both the 2002 and 2004 SAE conferences Melvin, Begeman and Foster authored papers comparing the performance of various H&N restraints on the 50G sled at WSU. Because the issue was relative performance, there was no question of absolute load levels at different impacts.

You would be doing exactly the same thing here, with the same sled and the same dummy. The only difference is that you rotate everything 90 degrees and dial down the impact.

[Eagle7]

Testing has shown that head loads are not a linear function of impact, but it&#39;s close enough that proportionality is used frequently as a rule of thumb for estimating absolute levels. For comparative purposes it&#39;s a non-issue, i.e. if a product has a certain head load reduction at 50Gs, say, it&#39;s reasonable to see the same general level of performance at different impacts.
[/b]
I&#39;ll be Earnhart&#39;s belts would have worked fine at 20G, but failed at a higher level. If the SkullSaver Supreme slips out of the harness at a high G level, isn&#39;t that a major non-linearity which a low-G crash wouldn&#39;t demonstrate?

[Doc Bro]

[quote]
...a dummy with no arms.

:happy204:

I&#39;ll leave that one to just sit for a while.....


R

[MMiskoe]

Well seeing as how we IT guys are driving considerably slower cars than those w/ the Big Money, what G&#39;s should we expect to see in a typical incident? We won&#39;t have 180mph impact w/ a fixed concrete wall (well maybe in ITR??)

I&#39;m thinking that you can&#39;t prepare for the absolute worst w/o just staying home. So what sorts of forces are invovled in a "typical" crash of an IT car (if there is one). This then gets back to where Kirk was going of at what point does a XXX type of restraint come into play. Do we play in a world where things like NASCAR softwalls even have an effect?

On the subject of side loads on H&N restraints, I unfortunately know that the seat plays a big part in a side impact. Case in point a side impact where the driver had left his Hans in the trailer did not survive, but unclear if the neck injuries or the abdominal injuries from the seat were to blame. Side load tests should include some testing to see where the seat becomes a bigger player than the H&N.

I am guessing that most of the frontal impact testing has shown how to restrain a body adequately, now the other directions need to be explored.


Dropping RV&#39;s on their nose sounds like way more fun the considering what could become of you in a racecar. How fast do you think the sled would need to be going to cut a 40&#39; motorhome in half when hit side on?

[gsbaker]

I&#39;ll be Earnhart&#39;s belts would have worked fine at 20G, but failed at a higher level. If the SkullSaver Supreme slips out of the harness at a high G level, isn&#39;t that a major non-linearity which a low-G crash wouldn&#39;t demonstrate?
[/b]
It could be, but that probably depends on the seat. The SSS slipped out of the harness at Delphi at 68Gs using a bench seat. But that was a 30 degree offset test, meaning the lateral component was 34Gs (sin30 = 0.5). If you can get as high as 20Gs (just guessing) you may see the same thing.

Seat selection will be critical, and I doubt anyone here wants to use a bench seat.

[lateapex911]

. How fast do you think the sled would need to be going to cut a 40&#39; motorhome in half when hit side on?
[/b]

7MPH?

Those things are such tin cans, LOL.

[Daryl DeArman]

So I would request that whatever test you do, meets the stupid SFI requirements.
Or put the entire organization on the sled and test them...sans anything for protection. And maybe toss on an SCCA lawyer type or two, just so they can feel what it will be like after I hit something having been required to take my Isaac off.
[/b]


Amen.

FWIW, I know my motorhome isn&#39;t exactly the safest thing on the road, but unless I get t-boned by something as big or bigger they are going to go right through the basement storage and hit a VERY beefy frame. I have a feeling they would be in worse shape than I, (not the vehicles). I&#39;ll escape through the large windshield that will surely pop out after by only other exit door is now inoperable.

Besides I have one of those really safe and strong Class A&#39;s that the salesmen tell you has the front cap constructed of 16ga steel instead of fiberglass like most of the competition. Great, sounds strong(er) because it has the STEEL word in its&#39; description, but an almost verticle section of 16ga sheet steel isn&#39;t exactly a crumple zone.

[Geo]

Since this thread was initiated solely for the purpose of amusement,...
[/b]

Well shoot Gregg, if this is purely for amusement, I&#39;d like to see a sled test with the dummy unbelted and unhelmeted. We could see just how far he&#39;d fly, or perhaps the farthest some pieces would fly. Bonus points would be to somehow add gasoline to the mix w/o Nomex.

Yes, I&#39;m a sick puppy..... :P

Actually, I like Jake&#39;s idea (I always like Jake&#39;s ideas) even better of putting the SFI organization on the sled sans belts or helmets. Of course you could still call it the Dummy Toss.....

[gsbaker]

Well shoot Gregg, if this is purely for amusement, I&#39;d like to see a sled test with the dummy unbelted and unhelmeted. We could see just how far he&#39;d fly, or perhaps the farthest some pieces would fly....[/b]
With or without a cup? :)


Yes, I&#39;m a sick puppy..... :P[/b]
Roger that. ;)


Actually, I like Jake&#39;s idea (I always like Jake&#39;s ideas) even better of putting the SFI organization on the sled sans belts or helmets. Of course you could still call it the Dummy Toss.....
[/b]
Those who write safety specs should be required to ride the sled.

[tderonne]

MMiskoe (Sorry don&#39;t know your name, and your profile has your website, but didn&#39;t work) post reflects what I hear the most, we just don&#39;t go fast enough, nor do we have such hard things to hit as the big boys.

I even make that argument myself. My 95 MPH Festiva is safer than a 135 MPH AS car.

Not sure how it relates to anything you could do on a sled though.

Tim.

[JIgou]

Man, the "We don&#39;t go fast enough to get hurt" statements really make me cringe.

Jarrod

[jake7140]

"And maybe toss on an SCCA lawyer type or two, just so they can feel what it will be like after I hit something having been required to take my Isaac off."

Perhaps a bucket filled with head cheese would replicate that sufficiently.

[gsbaker]

Man, the "We don&#39;t go fast enough to get hurt" statements really make me cringe.

Jarrod
[/b]
That&#39;s because you&#39;ve "crashed" without ever leaving the track. The car-hits-car scenario can get ugly.

I&#39;m going to get in trouble regardless of which why I go. If I acknowledge (which I do) that the probability of a severe impact is less in road racing than in circle track I could leave someone with the impression that protection is not needed; if I go the other way we&#39;re accused of fear mongering. So I&#39;ll offer a couple of quick facts and one opinion:

Fact 1. It&#39;s not how fast you go, it&#39;s how fast you stop. The 50G sled at WSU (which is nearly twice the lethal limit) runs at 35 mph. Earnhardt&#39;s velocity change was less than 50 mph, IIRC. Most drivers who crash will tell you that it feels worse than it looks on video.

Fact 2. If you lose your belts in a side impact you no longer have a head and neck problem, you have a body problem--especially in a multiple-impact scenario.

Opinion: Personally, I&#39;d rather crash the motorhome.

[tderonne]

Kind of had to cut that short, you bet it makes me cringe, wasn&#39;t saying it&#39;s a proper argument. Of cours everything is relative.

Here&#39;s something to think about.

35 MPH crash into something immobile is more than likely surviable in a modern car with a three point belt and an airbag or two.

Same 35 MPH crash in most of our racecars is NOT survivable without some sort of H&N restaint.

[lateapex911]

Well seeing as how we IT guys are driving considerably slower cars than those w/ the Big Money, what G&#39;s should we expect to see in a typical incident? We won&#39;t have 180mph impact w/ a fixed concrete wall (well maybe in ITR??)

[/b]


THis is a relevant point....

A recent helmet study showed that helmet specs that required protection to the skull in super high impacts were actually imparting higher loads on the skulls in lesser load crashes that were the statistical majority, than helmets designed for lesser specs.

In other words, certain helmets that were designed to pass the super slam test, did. But, the loads on the heads in those same helmets were much higher in lesser hits, than the loads on heads in helmets designed for other, less stringent specs.

As statistics show that most crashes were significantly less that the stricter spec prepared for, the conclusion is that that higher standard would actually cause more injuries than a lesser standard in most cases.

Helmet-wise, it would be good to have a helmet that could do both...be compliant enough to cushion the blow in lesser hits, yet resilient enough to protect in the huge hits.

The larger lesson here is that the basic thinking that "more is better" isn&#39;t always the case.

On of the reasons I like the Isaac is the "auto adjust" nature of it. The fluid dampers respond to the force present...more damping when needed, less when not. I think that for guys like us, in closed cockpit cars, it has several important advantages.

I am saddened by the relative blindness of the spec writing system.........

[Daryl DeArman]

A recent helmet study showed that helmet specs that required protection to the skull in super high impacts were actually imparting higher loads on the skulls in lesser load crashes that were the statistical majority, than helmets designed for lesser specs.

<SNIP>

Helmet-wise, it would be good to have a helmet that could do both...be compliant enough to cushion the blow in lesser hits, yet resilient enough to protect in the huge hits.
[/b]

Good points. An easy to relate to example is the cheap vs. good roll bar padding. The cheap stuff won&#39;t hurt you at a very low velocity (punch it with an easy jab), punch it hard and you wouldn&#39;t even know it was there. Worthless for our needs. The good stuff--doesn&#39;t feel like it would cushion much but I am pretty confident that if you whack your arm on it one good time--you&#39;ll be thankful it was there.

Helmets--how about a progressive density liner--or will the soft compliant stuff leave too much air space for secondary impacts?

[RacerBill]

"Those who write safety specs should be required to ride the sled."

For those who remember the good ol&#39; days at the Glen.....

THE SLED WANTS A LAWYER! THE SLED WANTS A LAWYER! THE SLED WANTS A LAWYER!