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Re: Parachute lines

To: "Dick J" <lsr_man@yahoo.com>, "Dave" <ddahlgren@snet.net>,
Subject: Re: Parachute lines
From: "Keith Turk" <kturk@ala.net>
Date: Tue, 7 Nov 2000 13:08:50 -0600
Dave I think I finally caught on to what you were saying... Try this....

FIXED mounting point of one end of the Rod.... Shock at the upper end with
a second rod hanging out the back... when you pull aft on the second
Parachute attaching rod you are pulling down on the Shock.....

don't know if that made a lick of sense but I understood it perfectly.... 

o------------  ------------ O
             s               I
             h               I
             o               I
             c               I
             k               I
                              I
                              I
                              O
                     parachute

now I wonder how that will come out on an E-mail

K
----------
> From: Dick J <lsr_man@yahoo.com>
> To: Dave <ddahlgren@snet.net>; Wester S Potter <wspotter@jps.net>
> Cc: Nafzger <nafzger@vtc.net>; land-speed@autox.team.net
> Subject: Parachute lines
> Date: Tuesday, November 07, 2000 12:47 PM
> 
> It would seem like a vintage 125 dirt bike shock
> would be just the thing for that.  They have nice
> long travel and a good progressive rate beginning
> the first inch or so of compression with about
> twenty pounds and increasing to 500+ pounds
> before they bottom out. Use a 2:1 arm and it
> should never reach bottom-out.  Migth be a good
> engineering experiment coming out of this.
> 
> Dick J
> 
> 
> --- Dave <ddahlgren@snet.net> wrote:
> > Thinking a little outside the box today.. I
> > wonder if a spring and shock
> > arrangement on a rocker system would soften the
> > hit of the chute.. If
> > you connect the chute line to a pull rod or
> > rods and then go through a
> > rocker arrangement you could push on a spring
> > and shock (coil over type)
> > and thereby take up the hit a lot softer. the
> > same as driving with a
> > solid suspension everything breaks or cracks
> > from all the instantaneous
> > loads.  i see no reason why this could not work
> > very effectively.. If
> > you know the speed and mass of the car and the
> > square ft. of the chute i
> > would think that an appropriate spring rate and
> > damping rate could be
> > calculated so the chute does not just bang open
> > and tear things up.
> > Might even make some of the hard to handle cars
> > a little smoother
> > too.... I am open for further discussion on
> > this.
> > Dave Dahlgren
> > 
> > Wester S Potter wrote:
> > > 
> > > Howard, List.
> > > The thing that disturbs me is that even after
> > several years there are still
> > > tethers that can't handle the stress and snap
> > so cleanly.  I'm aware of the
> > > programming Deist does and the results have
> > been impressive in stopping so
> > > many cars so many times, safely.  What scares
> > me is the fact that with the
> > > potental of eight or so 'liners capable of
> > 400 mph speeds this next year.
> > > This should bring the probable result of two
> > way record runs again.  On the
> > > South end of the course there won't be mud
> > for stopping.  We don't need more
> > > "Breedlove stops" in a pond somewhere or
> > someone running into a dike.
> > > As for a kevlar tether, the strength isn't
> > necessarily longitudinal from
> > > what I have been able to read ... the impact
> > resistance is based on a
> > > cushioning effect from the woven layers, of
> > which there are several (and the
> > > friction between them is the shock absorbing
> > quality), and the strength of
> > > the covering surfaces.  Ballistic nylon is
> > just that, ballistic, tough
> > > enough to slow the original hit
> > > What is needed is some strapping that will
> > hold up under the shock of the
> > > chute deployment jerk.  As an example,
> > Polypropylene rope is stronger in
> > > some ways than nylon for the same number of
> > strands and same thickness of
> > > strands.  There must be some composite that
> > could be core-spun or
> > > multi-fiber cording that could be manfactured
> > to handle the load.
> > > Just brainstorming and I'm probably all wet
> > but I'm very concerned about the
> > > potential for a dangerous situation.
> > > Wes
> > > 
> > > PS  ...  We once towed a '50 Chev 2 door for
> > thirty five miles on a very
> > > cold winter night using two strands of nylon
> > shroud line from a parachute.
> > > The stuff is great until it gets a solid hit,
> > as long as it can stretch a
> > > bit it's just fine.
> > > 
> > > W
> 
> 
> =====
> * * * * * * * * * * * * * *
> *         Dick J          * 
> *    (In East Texas)      *
> *         # 729           *
> * C/GRS   C/FRS    D/STR  *
> * * * * * * * * * * * * * *
> 
> __________________________________________________
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