0
skydiverek

Stowing slider in a rubberband: any downsides?

Recommended Posts

I wrote PD about it, and they only said they do not advocate it. Any downsides to this method???:

"UPT
September 5, 1986
Effective Immediately. Please stow main canopy slider in a rubber band which you have attached to the
center "B" line attachment point. (Do not stow it to the tail.)
Reason. Occasionally, during main canopy deployment, the collapsing drogue exerts so much force on the
deployment bag that some or all of the stowed suspension lines "slump" out of the rubber bands prematurely
causing a reverse sequence (canopy first) deployment.

A canopy first deployment usually works out OK. The
main problem is that if the slider is not stowed, .it too might slip down the suspension lines before line stretch
causing a hard or off center opening. An off center opening can concentrate opening forces on one portion of
the canopy or one line group. We believe this is responsible for several broken main rear risers which have
recently been reported to us. Broken risers are obviously not very common. This problem took many thousands
of drogue jumps to show up and we believe stowing the slider should prevent it.

I am working on a bag modification which I think may prevent line "slump" and will let you know as soon as
it is "perfected". In the meantime, I urge you not to experiment with other "solutions" such as using bungee
cord locking stows instead of standard rubber bands. In some instances, this could cause a bag lock which is
a far worse problem than already exists.

Sincerely,
William R. Booth
President"

Source:
http://unitedparachutetechnologies.com/PDF/Support/Product%20Service%20Bulletins/09218.pdf

***AND***

JUMPSHACK
TANDEM CANOPY ASSEMBLY
All canopies should have a rubber stow band attached to the line attachment point of one of the inboard “C” lines. The center of the slider should be
stowed in this retainer during packing. The purpose
of this retainer is to prevent the slider from coming
down the lines prematurely. It is a good idea to do
this to any canopy.

Other canopies may require that the stow band be
located on the “B” line. This may be determined by
pulling the center of the slider up into the center of
the air channel with the slider grommets firmly
against the slider stops. Observe where the point 3
to 4 inches from the center point of the slider falls,
and locate the stow band on the nearest line attachment point.

SOURCE, page 8:
http://www.jumpshack.com/download/Canopy_Owners_Manual_May_2008.pdf

Share this post


Link to post
Share on other sites
Quote

I wrote PD about it, and they only said they do not advocate it. Any downsides to this method???:



It is standard procedure within the competition to refute anything developed by Jump Shack. There is no down side to the procedure. We have been requiring it, in our manual to use a rubber band on all canopies since the beginning of Ram-airs in the 70's. I believe most manufacturers do now endorse the concept.

Having said that let me caution you to the fact that while the rubber band on the slider will keep the slider from "falling" or inertially being pulled down the lines during opening it will not hold/help if the canopy begins inflation (spreading) and forces the slider out of the rubber band and down the lines before you reach line stretch. This can only be prevented with a bag which will not allow line dump/strip.

Share this post


Link to post
Share on other sites
***I wrote PD about it, and they only said they do not advocate it. Any downsides to this method???:

"UPT
September 5, 1986
Effective Immediately. Please stow main canopy slider in a rubber band which you have attached to the
center "B" line attachment point. (Do not stow it to the tail.)
...............................................................................

Yes,
I remember when that was announced. A fellow TI stowed his slider - too tight - in a rubber band. The slider never came down. He cutaway and deployed his reserve. We never stowed another slider in a rubber band.

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

0