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From: gnosis@fluke.UUCP (Chris Villani)
Newsgroups: net.auto
Subject: Re: Harnesses vs. plain old seatbelts
Message-ID: <1474@vax3.fluke.UUCP>
Date: Thu, 19-Sep-85 19:24:49 EDT
Article-I.D.: vax3.1474
Posted: Thu Sep 19 19:24:49 1985
Date-Received: Sat, 21-Sep-85 04:41:28 EDT
References: <2778@harpo.UUCP> <149@emacs.uucp> <226@twitch.UUCP> <429@aero.ARPA>
Organization: John Fluke Mfg. Co., Inc., Everett, WA
Lines: 45

>  I find a lap belt adequate at keeping me in my
>seat in place while turning my fwd gerbil box with long tread life radials
>(which I occationally drive somewhat hard).  However, I question the security
>of a conventional lap belt/shoulder harness system.

The primary purpose of the shoulder strap is to keep you from needing dental
work after swallowing your steering wheel |-) and it will hopefully keep your
passenger from encountering the windscreen.

>    o Are the inertial seat belts less safe than the kind that remain static.
>      (they are certainly more convienent some of the time).

I have only heard of one instance in which an inertial type system failed in
an accident.  This was due to pilot error.  The vehicle was a BMW 5 series.
For some reason the owner had rerigged the system so that the strap exiting
the inertial reel was not vertical which is required for proper operation in
this case.  The result was some very sore ribs and a dent/bruise with a 
radius of curvature equal to the steering wheel across his forehead.  Lucky.
Also noteworthy:  when I was flying light aircraft in the Air Force we used
a 4 point harness system with the top 2 points attatched to an inertial reel
above and behind my head.  I personally prefer a static system with the
shoulder harness adjusted to allow unimpeded steering in an emergency
situation or competition (autocrosses and track sessions).

>    o Is the added confinement of a four point harness valuable in a
>      collision?  (i.e. can you fall out of the should part in a sideways
>      impact,  can the shoulder belt cause injury from bad placement?)

The more points the better as long as your ability to respond safely is
not compromised.  A snug static system will be of more benefit in a 
"sideways impact".  Proper placement of the shoulder strap is an absolute
must when small children are using them to prevent potentially fatal
neck injuries.  In fact it is often better to not use the shoulder strap
(runit behind the seat) with kids.  Generally kids are short enough
so they will not impact the dash.
>    o Is there any reason to use a five point harness in a street car?

I've never heard of such a thing.  Enlighten me!


In general the only reason we have inertial type systems is that people
bitch about the little extra hassle involved using static systems that 
are a little less comfortable but superior from a safety point of view.

Chris Villani