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Parachute lines

To: <land-speed@autox.team.net>
Subject: Parachute lines
From: "John Beckett" <landspeedracer@email.msn.com>
Date: Tue, 7 Nov 2000 20:10:10 -0500
List

Been busy thinking outside the box, so now I think I have it all figured
out. The issue is one of ballast. Almost none in a drag car and perhaps
thousands of lbs. in some LSR vehicles. Well accelerating the mass is a
factor but keeping the tires glued to the salt is the other major issue.
Ballast is the preferred method of maintaining that contact as it doesn't
cause aerodynamic drag.

Now the problem comes about when trying to slow all this mass. LSR vehicles
weigh 3 or 4 times what a drag car weighs. Consequently when the chute is
opened at high speed the strength limits of the materials used are quickly
reached and things start to fail.

So after discussions with another well known racer the following seems to be
the answer. LSR vehicles need to be built with a rear door similar to a
C-130. Ballast is positioned on a skid which is placed inside the vehicles
rear compartment. A drogue chute is attached to the skid, and when deployed
will pull the skid and ballast from the rear of the vehicle. In this way the
car may cut its over all mass by perhaps one half and therefore when the
regular parachute is deployed the stress on the chute is considerably
reduced as well as the distance required to stop.

A proper driving technique may be required as it is possible, depending on
the skid and drogue design, that the skid may slide faster and further than
the car itself. Therefor it would be recommended that drivers pull to the
left dump their load and move quickly to the right and out of the way before
pulling their main chute.

Just some thinking way outside the box.

JB

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