ScottMellor

As someone who has used the front of a full face helmet as a road-grinding device on a round-about in Coventry right in front of the Jaguar factory, (damned Laverda 750 SF2 exhaust balance pipe high centered) I'd rather it was the helmet than my face.

JCP911S

Ditto on FF... airbags are not "soft"... just softer than the windshield. Also the FF should not "hit you in the face" unless it is about 5 sizes too large.

I'd be interested in the actual dynamics of how a FF "breaks your jaw"... sounds like a lot of crap to me... but wierd things happen in real crashes

Bob Rouleau

Guys, I read a note elsewhere that the concern over the use of a full face helmet in a airbag equipped car is different from what we've been talking about. I read that that Ford Motor Co was the source - the risk they describe is a serious neck injury caused by the air bag deploying and hitting the lower front of the full face helmet and levering it up and back. I can see how this could cause a serious (broken!) neck injury. This makes a lot more sense to me than having a broken jaw which none of us could understand.

Rgds,

Geo

Yes. Someone on Bimmerforums has read the FIA report and says covered the use of airbags in a F1 car with a driver using the HANS.

Beware of people making safety decisions based upon poor testing and/or analysis. That is how we got the stupid 2 year belt rule. God only knows what's next. I'm so convinced that the 2 year SFI belt rule is a ploy to sell more belts that I've become cynical enough to wonder who has a hidden agenda here. And I'm not one to get cynical.

JCP911S

Bob R... agree... that was what I was describing...the energy in the airbag is scaled to match some percentage of the energy in your body in a relativley unrestrained crash (e.g. 3 points).... in order to to slow it down... that a whole bunch of energy.

However, If I have already lost most of my forward energy to 5-points, the airbag hitting me is putting more energy into me than I need and in the wrong direction.

Similarly, if the airbag hits the helmet at the wrong angle, the helmet does create a lever effect on your neck...

My sense is that airbags are designed as a system with an unprotected driver in 3 points.

5-Points, helments, race seats and H&N devices are a system.

Both have a pretty good track record by themselves.... I am very suspicious of "mixing and matching" elements from one system to another with no clear proof of effectiveness...

I don;t see airbags in race cars... is this just ingnorance or is hter a damned good reason for it....????

JCP911S

Geo.... any conclusions from that FIA report? I don;t see airbags on the F! cars today.

Also... two year rule may be overkill, but it certainly doesn't reduce your safety... in the overall scheme of things, $200 every other year is a pretty small portion of the average track/racing budget... I see guys at DE with belts that are so old they have mold on them...

Geo

I personally didn't read the report. All I have to go on for an answer is what I've heard in the media, i.e. that currently technology does not lend itself to F1.

People running really old belts are nuts.

But, your reaction to the 2 year rule is, IMHO, what SFI was counting on. I mean, come on, who is going to question a quest for greater safety? Well, perhaps we should.

The data SFI based their conclusions on was 40 years old and involved excellerated weathering of a type of nylon that is not even used in motorsports safety belts. Furthermore, I wrote to SFI and got a copy of their testing procedures and even as a layman monkey I can say their testing procedure is pretty lame. In SCCA's Sports Car it was reported how SFI tests belts, but it didn't wash in any way shape for form with the documents sent to me by SFI. The documents sent to me by SFI indicated the only tests they do are static. ABSOLUTELY NO SLED TESTING. Furthermore, the US military does not replace belts in any time limit. They are a replace as needed item. Helicopters live in a much worse environment than race cars (sun, salt water, etc) plus they get considerably more use and crashes are just as or more violent. We got hoodwinked. I did a lot of research on this when the SCCA announced their plans and unfortunately couldn't get my response into them before they finalized their decision. I can only hope everyone buys FIA homologated belts leaving SFI belt manufacturers desiring to change their minds.

Bad testing and/or analysis should NOT be acceptable where our safety is an issue. Again, I'm usually not cynical, but I think there are those with their own agenda pushing some decisions.

I think the only thing keeping helmet rules rational is the fact that the Snell Memorial Foundation is independent. I wish all safety product testing was done by independent groups. SFI is absolutely NOT independent. It's run by and serves the industry.

JCP911S

Geo... much bigger picture here than a 2-year replacement rule... which is a prety CYA thing anyway...
Interesting info on the testing procedures... its easy to assume folks know what they are doing.... maybe not..... so the FIA does a better job, you think? I've heard some lackluster things about the FIA testing of seats... that they set a "pass" limit at 20Gs.... which seems pretty low for some of the hits folks can take in these cars.... and they are focused more on keeping the seat intact than on the ablity to protect the driver... two different things.

Appreciate you putting out the effort to check up on this stuff

Geo

I definitely trust the FIA more than SFI. I trust Snell more than anyone.

I'll try to see if I can scare up the SFI testing procedures. IIRC (but it's been 2 years and my memory could be a bit fuzzy) they do a static test with a set force for a period of time (less that 30 seconds IIRC) pulling along the length of the belts. It's really insanely stupid. I'm not an engineer, but understand physics and engineering enough to not place any faith in such a test.

What really bothers me is the article in Sports Car, the testing claimed for SFI in the article had absolutely nothing to do with the procedures they sent me. I do not trust SFI in the least. The problem is, who else is there to do testing? Snell has their hands full with helmets. The FIA, while not always state of the art at least is independent.

And while there may be issues with FIA seat testing, they are the only ones doing any independent testing that I know of.

fatbillybob

FWIW,

Dealing with airbags is not difficult. I am no mechanic but Some cars have a dedicated fuse to these systems you can just pull before a race or DE. Some cars have different colored connectors like blue to denote airbags so mechanics do not play with them by accident. You can pull a plug here and kill the system. Just be careful to not have statically charged hands upon removal and keep your head body away from the bag just in case.

YMMV

JCP911S

Geo... what about Simpson.... do they do testing? Yes, I know thay are not independant, but that does not mean scientifically proper results are not valid.

Geo

I don't know what Simpson does. I am not so sure manufacturers have our best interests in mind always.

I'd rather see independent testing of all safety gear.

RedlineMan

Hmmmm...

I think I tend to be with Geo on this, in that I want to see testing before I believe that air bags cause "excess rotation" of the head forward with a full face helmet.

Watch any film of a sled test depicting a forward impact. The reality is that rotating forward is exactly what the head does already in such cases, and it is this phenominon that the HANS device (and I might imagine ALL H&N devices to some degree) exploits to reduce neck tension and transfer it through the helmet into the forehead, which is struturally the strongest portion of the skull as I know it.

If anything, I could surmise that the deploymewnt of an airbag might DECREASE this forward rotation of the head. If it did so, might that not also DECREASE the effectiveness of a H&N device in transfering loads into the forehead?

Yep... I wanna see the physical data on this one!

JCP911S

So what happens if I throw half a ton of apples into a tornado?

Too many variables here to speculate. Airbags desiged to work with specific combination of pretensionsed 3-point belts seats and body crushzZones and interior space. The timing is critical to thousands of a second.

Scenario A: Say I hit something head on and I stretch the 5-points to maximum, the H&N to max and am full at a stop when the airbag goes off... this is like having a second collision and causes the exact sort of rebound impact that most people agree causes maximum brain and spinal injury.... BAD NEWS.

Scenario B: Say I hit something head on and the airbag deploys just as I begin to hit the harnesses... in this case the airbag works in conjunction with the belts to reduce impact...

The difference between A and B could be a few thousands of a second...

Scenario C: I have a 1/4 frontal impact on the left front... now my head and body are twisting when the airbag deploys, hitting the chin guard of the helment from the side and accellerating the rotational impact dramatically... it is these shearing impacts that most people say are the most damaging...

Who knows... but it seems like with full race safety equipment, the airbag throws a huge unknown into the equation with alot of independant energy an deployment timing that is not synchronized with the performance of the rest of the elements

Geo

Hopefully you'll duck and cover.