ltc

I know this was discussed a LONG time ago, but I just stumbled on some details on these harnesses...

http://www.schrothracing.com/info/9

mooty

i have seen this.
but i think you may really need someone to help you strap in with all those belts around you, no?
i dont know, just wondering.

fatbillybob

I got them. You can do it one person. Kinda a pain. Work o.k.. Not sure I wiould buy them again. Very expensive

mooty

thanx for the info, i will stay with my 3 to 2 hans belt then.

PedroNole

I've got this system as well. One person can definitely do the belts, even with a helmet and Hans already on.... I highly recommend it but definitely get the Hans (2") belts for shoulders

JBH

That is a pretty useful reference - the first time I have seen an explanation for the D-rings used in Formula cars. They are a PITA to fasten, but now I better understand the purpose and function.

Thanks for the post.

fatbillybob

Huh? You mean they make a 2" body belt with a 2" hans belt combo vs the 3" body 2" hans? Why use the the 2+2? Does it work beter or more user friendly in some way?

ltc

This is interesting (from the link referenced in the first post):

The only complications of this setup are in the installation. It is CRITICAL to install these belts correctly. Failure to do this correctly may result in driver injury. The body belt (3" shoulder strap) must angle down off the shoulders at an angle between 20 and 30 degrees down from parallel to the ground. The HANS belt (2" shoulder strap) needs to come off closer to 10 degrees and angle in more than the body belt does.

Please Note: the Schroth Double Belt can provide your driver with the state of the art in safety restraints. It can only do this if mounting geometry is Ideal. Modifications to a standard roll cage will probably be necessary, and failure to do these modifications correctly can result in serious driver injury.

When I was up at HMSMotorsport a couple of years back, they showed me an adapter, fabricated by Penske Motorsports South (NA$CAR group) to allow for both belts to terminate on a single horizontal rollbar/rollcage crossmember.
You simply located and welded this adapter at the proper spacing and proper position to get the proper termination/angles. Pretty neat idea.

FWIW and IMHO, as an engineer, I've always been fascinated by the evolution of the HANS, especially its interface to the harnesses.
I am still somewhat confused at all the recommendations/changes (and in some cases contradictions) regarding the shoulder belt interface; first 3" shoulder belts, no wings, then the 3-2: HANS specific shoulder belts, then the wings, then the 3" shoulder belts overlapping the wings, then H&D saying that there is no reason for a 3-2" HANS specific shoulder belt.
I am curious to see if H&D takes an (official) position on the double shoulder belt harness.

SundayDriver

I looked at using these belts when I replaced mine for this year. As ltc points out, the installation requirements were pretty severe and there was no way to do that in my car without a major amount of work to the tube structure.

How much extra roll cage structure did you guys have to do when installing for a production car? Seems very challenging to get the belt mounts at just the right heights. I would like to see photos if anyone has them.

SundayDriver

Yes (that is what I have in the formula car version). The latest info indicates that 2" laps fit better with the pelvis than 3". Combined with the HANS specific shoulder belts gives that combination. I have found the 2" laps to be far better fitting and more comfortable in my lay down car, than the 3" set ups. The HANS shoulder belts are easier to get mounted at a very narrow dimension. The result is a set of belts that fit me great.

PedroNole

Yep, however, I meant (as I said in the post) the 2" shoulder belts.

fatbillybob

I understand what you are talking about but the previous poster posts sounds like a 2" body belt shoulder with a 2" hans belt shoulder.

SundayDriver

Got it - I misunderstood.

fatbillybob

Item 1 was not in the last FIA 2005 hans set-up guide. I do not know if those words are now in the new one. There are all kinds of funky rules in the FIA guide. I have it as a pdf file but do not know how to post it here. I could e-mail it to someone if they want. fatbillybob@yahoo.com

item 2 I would like to see a nobrainer weld in mount.

item 3 A couple yrs ago I was at a seminar with Dr. Hubbard and he said if he raced he would use the 2x shoulder strap eventhough hans position is 3" is all you need and was the hans reccomended set-up at the time. For that reason alone I have stuck with these 2x shoulders.

fatbillybob

This is a 2x shoulder in a pro car

this is my car with the hanress bar at the right height for my shoulders

my sideview with belts

a rear view

and that's how it hangs from the front