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Re: parachutes

To: "Nafzger" <nafzger@vtc.net>, "Scott Cowle" <scowle@mentorcollege.edu>,
Subject: Re: parachutes
From: "Nafzger" <nafzger@vtc.net>
Date: Mon, 25 Sep 2000 10:14:38 -0700
Scott,
 One additional comment, the chute clevis or mounting point should be at the
centerline of the car. (i.e., between the tread width).  That seems obvious
but I have seen it done other than that.  We actually reinforced the frame
rails on my car with 4x4's and balanced it in a piece of heavy wall well
casing but you could use jack stands or whatever.  We had the battery in,
fuel,water, chutes, and even a few 9" pumpkins etc. in the drivers seat to
simulate my weight. (those bathroom scales are handy).  I had some problems
with this on my first car so did the research on the new car and it works
flawlessly. (when the chutes come out, but that's another problem that I am
working on right now and must get out to the shop and get busy.
Good luck,

Howard Nafzger
448 B/FS

----- Original Message -----
From: "Nafzger" <nafzger@vtc.net>
To: "Scott Cowle" <scowle@mentorcollege.edu>; <land-speed@autox.team.net>
Sent: Monday, September 25, 2000 9:36 AM
Subject: Re: parachutes


> Scott,
>
>  If the parachute is designed properly and even more critically, attached
at
> the correct point on your car, it should not upset the balance of the car
at
> all.  You must first find the fore and aft balance point of the car
weighted
> as it runs, then do your best guess on the vertical center of gravity
(based
> on where you sit and how high the engine is mounted, etc). You attach a
> string to that point on the car where the vertical and horizontal CG's
> intersect, walk back behind the car with the string held at arms reach
over
> your head until the string intersects a point in the car where you can
> rigidly mount a chute clevis. That tells you where the chute will pull
right
> down thru the CG of the car and how long your tow line and shroud lines
> should be. I personally like a tow line of 40 to 50 feet on streamliners.
> If done this way, the car is safe and stable under the chute with no evil
> tendencies.
> If the chute is sized correctly, it will be noticible but not violent when
> it opens. Get expert advise from on of the chute builders.
> I hope this helps, it has worked well for me.
>
> Howard Nafzger
> ----- Original Message -----
> From: "Scott Cowle" <scowle@mentorcollege.edu>
> To: <land-speed@autox.team.net>
> Sent: Monday, September 25, 2000 5:03 AM
> Subject: parachutes
>
>
> >   To All on the List,
> > Next year I'll have to run a parachute and I have two Questions:
> > 1) Does the chute move the car around when it is opened and if so what
do
> > you do about it ?
> > 2) How much drag does it apply upon opening, is it dramatic or is it
just
> > noticable ?
> > Thanks for your help,  Scott
> >
>


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