wrote:
In the USA, there isn't really any life span of canopies set for by
the FAA. However, some manufacturers are limiting their life span of
canopies, or harness/containers systems. For example, National limits
their life span to 15 years, Paraphernalia Softie is doing the same,
but Strong Enterprises rigs are good to use as long as they pass the
canopy/canopy fabric tests.

Do the manufacturers give a reason for this, such as discovering
parachutes that are no longer safe after 15 years, or industry tests
that shows fabric deteriorates in a manner that can't be found by
inspection? Or is this simply a convenient way to limit their liability?
Without knowing more, I see no reason to buy anything but a Strong
parachute. Why buy a parachute that's worthless (or maybe unsafe) after
15 years?

From what you say below, there are many stress factors on a parachute,
and the implication is the industry (or at least some of it) doesn't
know to test for potential problems. What puzzles me is these packing an
usage stresses don't seem very demanding for synthetic fabrics. Sport
parachutes get much more handling and use (jumping a parachute seems
like far more stress than using it as a cushion!), so it's hard to
understand why our chutes should degrade significantly in 15 years.

On the other hand, Performance Designs
wants to see reserve canopies in their factory after 40 repack cycles.
If the canopy passes the tests they will return it back to you and you
are good to go. Having said that, me as a rigger, I am not repacking
parachutes that are older than 15 years. And in general, if I remember
correctly, the PIA (Parachute Industry Association) also agrees that 15
years is the "life span" of a canopy but I am not quite positive on
that. I'll check with them and let you know. The problem with
parachutes is not the age alone. There is some other factors playing
important role in the fabric degradation. The main factor is the repack
cycle. According to the FAA, if your canopy is made of synthetic fibers
the repack cycle is 120 days and 60 days in a case on natural fibers
but that is history. The main degradation of fabric comes from handling
and repacking the canopy. When the rig is due for a repack the canopy
is pulled out of container or deployment bag in a case of sport
parachute. Then the rigger inspects the whole system, let the canopy
dry up and if everything is a OK it goes back into the container or
deployment bag. This insertion into the deployment bag or container is
the biggest stress for the fabric. And then you fly in it. You sit on
it. It works in some cases as a cushion. And after your are done
flying, you leave it in the direct sunlight, high temperatures and then
when you put your glider away in the trailer the poor rig is being
cooked. In some cases people will take them home....well, at list they
were attempting that, because the rig rides in a trunk of your car in
heat and cold. There is a push from the industry with the FAA to change
the repack cycle to 180 days. That will help with multiple issues. I
jumped a main sport parachute that sit in a deployment bag for over 2
years. It worked just fine. Still, I believe that a good parachute is
worth spending the money and it is worth of having and flying with it.



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Eric Greenwell
Washington State
USA