[F500] Re: HANS (fwd)

[Jamie Clark]

Good explaintation of added benefits of HANS from the inventor.

        Jamie Clark

---------- Forwarded message ----------
Date: Wed, 28 Aug 2002 11:52:11 -0400
From: Dr. Bob Hubbard <hubbard at egr.msu.edu>
To: Jamie Clark <jamie at datakids.org>
Cc: info at hansdevice.com
Subject: Re: HANS

Jamie,

Thanks for the quick reply.  I'm glad that the HANS helped you.

Your understanding of head injury is not quite accurate.  While the brain 
is not securely fastened to the skull except across the lower brain where 
there are major nerves and blood vessels through the base of the skull, the 
brain is not free to move because it is filled and surrounded by fluid 
(primarily water).  The least motions of the brain relative to the skull 
possible are straight line motions and rotary motions are more 
possible.  The brain in the skull is somewhat like one of those winter 
scenes with the "snow" in them.  If you move it quickly in a straight line, 
the snow does not fly.  But if you rotate it quick, you get a snow storm.

The major action of the HANS is to keep the head from swinging.  This does 
two things: 1. it reduces the stretch of the neck which otherwise could 
cause a basal skull fracture, and 2. it reduces the rotation of the head 
which otherwise could cause brain injury.

A few other drivers have reported some discomfort in the front of their 
heads after a big hit with HANS.  As with you, this quickly resolves.  The 
medical people in racing tell me that this is minor relative to what would 
have happened without HANS.

In study of racing safety, we have learned that loads and accelerations on 
the driver are best reduced by coupling the body as well as possible to the 
chassis.  While it may be possible to reduce peak loads in some cases by 
adding some cushion or compliance to the restraints, this generally leads 
to higher loads on people because it allows a larger difference in velocity 
between them and the chassis before they are restrained.  In the case of 
the HANS, there is a lot of compliance in the restraint belt and body; we 
do not need to add more compliance in the HANS.

I hope that this helps you understand HANS.  I look forward to get the 
photos.  Please contact me with any other questions.

Dr. Bob Hubbard

At 10:09 AM 8/28/2002 -0400, you wrote:
>On Wed, 28 Aug 2002, Dr. Bob Hubbard wrote:
>
> > Jamie,
> >
> > We are aware that you had a pretty bad racing crash while wearing a
> > HANS.  I'm interested in the details of the crash and your injuries.  This
> > helps us understand real racing crashes better and the role of HANS in
> > reducing injuries.
> >
> > Please send me any information that you have: your description of your
> > crash and injuries, photos of the car, the helmet and HANS that you were
> > wearing, or ...
>
>Thanks for contacting me and I am very pleased to see great advances in
>safety for racing.
>
>It happened during the qfy session for Summit Point National (Summit
>Point, WVa) in first weekend of April this year.
>
>I was driving Formula Mazda and I was ready to go for the flying lap and
>before the last turn (turn 10 which is the fastest corner on that track,
>about 95 MPH).
>
>Right after apex, I see that FC has spun in the middle of track, I took
>off the accleration pedal and try to stay at outside of the track exiting
>the corner, but that FC rolled his car to the outside so I decide to go
>inside of track at last minute and my car oversteer and there was other FF
>behind me and he could not avoid me and hit me on the sideways then hit
>the tire wall with concrete retaining wall behind the tire wall at around
>80 MPH head on (I have Motec data logging and it showed around 80 MPH
>before dropping down quickly during crash).
>
>I was fine except for bit dazed.  I don't have any bruises at all. The
>only after-effects of the crash was my brain, the front part of brain is
>like "bruise" and I had light headache for a week, very light headache,
>but I can feel it is inside the front part of the brain. Bit groggly, you
>know, not feeling 100% normal inside the front part of brain.  But after a
>week or two, then I was back to 100% normal.
>
>Looks like the front part of brain slammed against the frontal skull
>result in light "brain bruise".
>
>Thanks to your device, it defintely saved my neck and baslar skull
>fracture thing.  But I was wondering if someone is going head on at like
>125-150 MPH, the brain would slammed against the base of skull very hard
>and would result in serious concussion...  But that is far much better
>than baslar skull fracture anyway.
>
>I was thinking of having special strap that connect between HANS device to
>helmet that would stretch some (like a rubber band) which would spread the
>loading of brain into skull more over time than currently...
>
>My Formula Mazda lost all three corners (LF, RF, RR) and nose of
>car was wiped out so do the support frame for nose, but the main chassis
>frame is fine.  Having a good single tire wall front of concrete retaining
>wall (it is pit wall) sure helps with spread the loading of G force
>and lessen the injury to me and lessen damage to the car.
>
>Let me know if you have any questions, thanks
>
>         Jamie
>
> > Thanks in advance,
> > Dr. Bob Hubbard,
> > HANS inventor
> >
> > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> > Robert P. Hubbard, Ph.D., Professor
> > Department of Mechanical Engineering
> > 2555 Engineering Building
> > Michigan State University
> > East Lansing, MI 48824-1226
> >
> > Office location: 4135 Engineering Building
> > Voice: 517 353 5013
> > Fax: 517 353 4472
> > Email: hubbard at msu.edu
> >
>
>--
>         Jamie Clark

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Robert P. Hubbard, Ph.D., Professor
Department of Mechanical Engineering
2555 Engineering Building
Michigan State University
East Lansing, MI 48824-1226

Office location: 4135 Engineering Building
Voice: 517 353 5013
Fax: 517 353 4472
Email: hubbard at msu.edu