RedlineMan

Ummm... as a matter of fact;



Nothing against you at all Plavan. I was not lumping you into my criticism of the photo that was posted.

But Halos are not the point. Would all here not think it a little more enlightening to see an apples-to-apples comparison of an offset hit using both devices? Would all not say that this type of "advertising" is extremely disingenuous... once you note the glaring inconsistency?

Do HANS devices sometimes escape the belts? Yes, quite obviously. In that circumstance, they don't provide much of a reduction in neck tension. We can safely assume the numbers are not good here. That is all this photo "proves."

Do R3s do a better job in the offset scenario? We don't know that because we have no numbers and it would be folly to guess at them. Numbers don't lie. Not like photos can. It might be fair and accurate to assume that the R3 stands to be superior because it does not directly rely on the belts. Assumptions can get you killed, of course.

Personally, I think the R3 probably does give some advantage here, but not as much as might be assumed if you dig a little deeper. There are other factors at work in an offset hit. The neck is much more prone to catastrophic damage in an offset because it does not have nearly the lateral range of motion or flexibility as with a frontal impact. The range at which restraint can be helpful and must be applied must therefore be reduced significantly over that of frontal impacts.

Assuming the HANS stays put under the belts, it's functional length as a restraint device is limited to the length of its tethers. Your head/neck will only move the 6" of tether length before negative tension against neck extension is realized.

The R3's functional length is that of its tethers (short), but also that of the yoke itself. In a frontal impact, it being a non-maleable material, it will not add any length to the overal restraint before negative tension is realized. In other words, the yoke transfer load immediately. I seem to recall it's neck tension numbers are "quite a bit higher" than HANS or Isaac. This is assumed to be the result of how it "attaches" to the body. It relies - and "falls victim to" - the same phenomena as the other strap devices (Hutchens, D-Cel). Straps stretch, slide on the body and clothing and skin before hard skeletal points are met and retention takes up in earnest. Having said that, the R3 offers numbers well within the surviveability range. Injury range is another measure altogether, and quite variable.

However, because of the way it "attaches" to the occupant, it seems to now be reliant on a couple of other factors. Will the load on the yoke press it into the body hard enough to keep it from slipping sideways? I personally doubt it. Will the "head rest" portion of the yoke catch on the belts and thus prevent it from swinging sideways? Now IT IS relying on the belts, if this scenario is true. Maybe it will catch, maybe not? We know the belts are stretching. Will they stay taught enough to provide assitance to the R3?

If they do not, then the whole assembly would seemingly stand to effectively "pivot" where the chest strap is attached, adding this much extension to the previously discussed lag in taking up on hard body points. This swinging sideways and drastically increasing the amount of head extension would seem to render it less than effective in an offset. That is... unless there was a halo there to stop the lateral movement of the head... like in the photo.

Blah, blah, blah... A lot of theorizing The photo proves that HANS devices can come astray. It also proves that side nets are worthwhile, and head halos are very effective. It doesn't show any advantage of the R3 over the HANS. Not in my book. Wouldn't it be nice if someone gathered all the H&N devices and did apples-to-apples testing for us?

I just wanted people to dig deeper and think more critically!

fatbillybob

GBaker,
Perhaps that's why Dr. H prefers the 4 shoulder strap method? Perhaps if you loose the HANS then you "may" still have belts but better "hope" the 2nd impact does not have an "injury threshold" forward componant??

gbaker

FBB,

Good point. Four belts would seem to help.

gbaker

...and it's only worse with videos.

Someone has already volunteered to do that:

http://www.headrestraint.org

Our understanding is that these guys are planning on collecting crash data infomation, distilling it, and presenting it to racers without it passing through some marketing department. A lot of data already exists, but if you have a specific test in mind they could contract the side-by-side testing of the Isaac system, HANS device and the R3 if everyone on this board kicked in, say, $20.

If you are serious about evaluating your choices, throw your lunch money their way and make it happen.

Plavan

John, no offense taken. This is a free country . I just thought that you being an instructor, would really see the benefits of using the R3. From jumping from car to car. Anyway, alot of Cart racers are taking to the R3 as well, because they do not have seat belts.
When you put on your R3, the shoulder portion does get pressed down by the harness, so in-fact the belts do help the R3, it just does not rely on them. You do not have to think, worry about, or preform and harness changes with the R3. In the test collision your whole body (Neck, torso, head) maintain the same relationship while moving forward after an impact. That may be the reason why you see broken collar bones with the Hans after some impacts. The Hans device can "dig in" when moving forward after impact, kinda like a lever.
Anyway- both devices will work, and they have +'s and -'s. These are the devices that any racer should look into purchasing.
Coke and Pepsi..... There is a market for both. Hans is not the only company making items for our safety now, we all have an advantage because of that.
Cheers-

fatbillybob

I wonder if the inventor of the R3 saw his girlfriend put on a HANS backwards and say "how does this think work"? Then has a forehead slapping moment and voila the elegant design of the R3. I wonder if crash crews who would normally put a back board on an injured driver would just save the time, cut the helmet straps, remove helmet and tape the forehead to the R3? It looks like it could be a real advantage to emergency crews and thus drivers.

RedlineMan

Thanks Chad;

I definitely DO see some advantage to the R3. I think it is a fine product, and remain somewhat torn between getting one and keeping my HANS. The extra versatility may more than make up for the lesser ultimate performance. Unfortunately, they did not exist when I bought my HANS.

By the by... Look for my Ultra Lap order soon. As soon as I can get my client's security code!