We are often asked which is the best parachute folding
technique. The problem is there really is no "best" procedure
for all situations. A lot depends on how much the parachute
needs to be packed, what the resulting size and shape needs to
be and how fast you want it to open. There are also a wide
variety of parachute shapes and sizes. What works for one does
not necessarily work for another. A parafoil for example is
packed very differently to a parasheet.
One of the main criteria though is that it should open
cleanly, and so careful preparation is necessary.
Existing Tutorials
There are quite a few tutorials available already on line.
Here are just a few examples of the variety of styles:
http://www.youtube.com/watch?v=dN5LzZJmP10 - posted by
MartySchrader. Folding a plastic chute for a model rocket.
Folding and shroud lines on the inside. Lots of useful tips.
After initially using the simple wrap the shroud lines over the canopy
technique, we suffered the occasional tangle or getting caught
up on on part of the deployment mechanism. We were then
introduced to the following procedure:
http://ausrocketry.com/forum/viewtopic.php?f=9&t=480.
An almost identical procedure is also described in this video:
http://www.youtube.com/watch?v=dN5LzZJmP10
Since we have started using the above technique we've only
had very rare tangles. This was often the result of the parachute
getting caught on a fin during deployment when the shock cord
was too short. The following procedure describes how we pack our
parachutes made from ripstop nylon for use with the side
deployment mechanism:
Procedure
0.
Pack your parachute just prior to
launch. Don't pack your parachute the night before.
1.
Shake out the parachute holding it by
its shroud lines. Make sure you fully inflate it by
swinging it around. This makes sure sections of the
canopy aren't sticking together. You should always do
this before each launch. Also check if any of the shroud
lines are crossed over, and untangle them. This is often
the result of a landing when a parachute can be inverted
and thread through some of the lines.
2.
Grab the end of the shroud lines and
the tip of the parachute and pull it out straight.
3.
Lay the parachute on a flat surface and
bring all the shroud lines together.
Go through each
of the sections of the parachute and make sure they are
all sitting flat and do not have any folds in them.
4.
Fold the shroud lines in half and
neatly lay them in the parachute.
5.
Fold the parachute over in half so that
you can't see any of the shroud lines.
6.
Fold the opposite side over. You can
fold it again to get a thinner pack.
7.
Fold the tip of the parachute over.
8.
Now depending how tall you want your
packed parachute to be, you may want to vary the number
of folds. Another one or 2 folds are normally good
enough.
9.
Fold the bottom of the canopy over
(where the shroud lines are) so that the shock cord
sticks out the middle.
10.
Fold it over again so that the shock
cord sticks out at one end.
11.
Wrap the shock cord over the canopy
pulling it tight to make the package smaller. When you
wrap your shock cord rotate the parachute rather than
winding the shock cord over it. This helps prevent a
twist developing in the shock cord.
We usually only wrap the parachute about 5-8 times. A
lot more turns means that the parachute will take longer
to open. We try not to cross over the shock cord loops.
I'm not sure if that's important or not, but it makes
the parachute neater and compact. Having folded the
parachute this way means there is less chance of the
bottom of the shroud lines getting caught up on anything
in the deployment mechanism.
And that's it.
Hints and Tips
If your parachute is wet either from
spilling water on it, or dew from landing on the ground,
make sure you dry it as best you can before packing.
People recommend using talcum powder on plastic
parachutes to help prevent them clinging together during a
deploy.
Don't store your parachute folded up. Store it
hanging by the shroud lines.
