Parachute 20 year limit

Gosh, where to begin ...

Not a whole lot of direct comparison testing has been done to my
knowledge because it was always patently obvious to those using and
making parachutes that squares open a LOT faster than rounds. You can
pack a square parachute to open nearly instantly by leaving the slider
down -- this is what BASE jumpers do, for obvious reasons. It is
dangerous, and unhealthy, to deploy a square chute with the slider
down; it can break your neck.

Square chutes had only recently been around when I started jumping in
1980 and they were still perfecting the reefing systems. Broken
suspension lines and blown cells (in the canopy) were common problems.
If you wanted soft and slow openings, you jumped a military surplus
(round) T-10!

My third square chute, which I jumped from 1989 to 1993, was notorious
for opening fast. I tried every trick in the book to slow it down. It
wasn't diagnosed until 1994 but I did permanent damage to the nerve
channels in my neck over the 900 jumps I put on that canopy (4-way
team training will make you cut corners packing). (The neurosurgeon's
comment as he was looking at the x-rays and MRIs was classic. I had
not told him of my skydiving history. He stared at one image after
another and finally looked at me and said "You could not have been in
500 car crashes...")

Anyway, don't take my word for it that squares by their nature open
faster than rounds. Call any harness/container or parachute
manufacturer. My container was made by Rigging Innovations (the owner
is Sandy Reid, the same guy in the photo on the top left of page 236
in the book referenced by Gregg; he'll be happy to answer your
questions). My chute is a Performance Designs reserve; call their
factory in Florida. I believe Bill Coe, the company's founder, is
still the owner.

And ask yourself ... if you're going to jump off the New River Gorge
Bridge with the intention of surviving, would you choose to do so with
a round or square parachute?

Dang this eggnog is good

~ted/2NO

My comment at the end of the first paragraph applies only to
deployments at terminal velocity, of course.

2NO

Gregg Ballou wrote:

At 23:58 09 December 2008, Eric Greenwell wrote:

Are there published tests for opening times?

http://books.google.com/books?id=2Po...sult#PPA235,M1
Hope the link works. Read pages 234 and 235. There is info on
deployment
speed and reliability. I rest my case.

Now I'm confused. I don't have notes from my March 2008 calls, but
before I made my purchase, I talked to two major parachute
manufacturers, one of which makes a ram reserve, and also a well known
rigger. What I recall is they all encouraged me to stick with the round
parachute for my glider. One reason I recall was the round emergency was
more tolerant of body position during opening. These same people also
made similar comments to the ones made here about the advantages of the
round emergency for the untrained "jumper" (like me - I'm just a pilot).

Another issue I think recall correctly, was I could find only one
company supplying a ram air parachute that they claimed was suitable for
the "lightly" trained pilot looking for an emergency parachute. I wasn't
persuaded by what they said on their website that it's advantages were
small and might not actually exceed the disadvantages.

There was puzzling statement on page 235 of Poynters book:

"Round canopies blow up more often, possibly 30% in normal use."

This sounds incredible for certified emergency parachutes, and it makes
me wonder if he is even talking about the same thing I am, where "normal
use" is 20 years as a seat cushion, and very rarely, only one jump in
it's entire service life. My perception is round emergency parachutes
function properly with failure rates far less than 30%.

--
Eric Greenwell - Washington State, USA
* Change "netto" to "net" to email me directly

* Updated! "Transponders in Sailplanes" http://tinyurl.com/y739x4
* New Jan '08 - sections on Mode S, TPAS, ADS-B, Flarm, more

* "A Guide to Self-launching Sailplane Operation" at www.motorglider.org

Eric,

Poynter's statement was about round parachutes in general, not
reserves, and by 30% he was comparing the malfunction rates to each
other; he did not mean to say that round parachutes malfunctioned 30%
of the time.

I would very like to know who you spoke to in March. Though I am not
surprised that a manufacturer would encourage you to stick with a
round chute -- they make money selling you either kind, and think that
they assume a liability risk if they do anything but tell an
"untrained jumper" to use a round parachute.

The fact is, "square parachutes require training". But consider the
target audiences -- just about anybody can go make a parachute jump.
Licensed glider pilots have a FAR higher general compentency level
than your average yahoo. (At least in Arizona And I can assure you
that operating square *reserve* parachutes is an EASY thing for glider
pilots to do.

2NO

I don't buy the stable body position argument either. Students have been
deploying square parachutes from all sorts of unimaginable body positions
for over 20 years. I've seen some doozies- the parachutes always
worked. It does have an effect but it is rather small and I doubt there
is an advantage round/square. Body position does matter for deploying
high wing loaded elliptical main parachutes used by experienced jumpers
but those are a different beast. FYI Skydiving students are taught:
1. To Pull
2. To pull at the proper altitude
3. To pull with stability(not to compromise #2)
I'm not saying burn your rounds but anyone in the market for a new
parachute should seriously consider going to a square.

At 04:06 10 December 2008, Eric Greenwell wrote:
Gregg Ballou wrote:

At 23:58 09 December 2008, Eric Greenwell wrote:

Are there published tests for opening times?

http://books.google.com/books?id=2Po...sult#PPA235,M1
Hope the link works. Read pages 234 and 235. There is info on
deployment
speed and reliability. I rest my case.

Now I'm confused. I don't have notes from my March 2008 calls, but
before I made my purchase, I talked to two major parachute
manufacturers, one of which makes a ram reserve, and also a well known
rigger. What I recall is they all encouraged me to stick with the round
parachute for my glider. One reason I recall was the round emergency was

more tolerant of body position during opening. These same people also
made similar comments to the ones made here about the advantages of the
round emergency for the untrained "jumper" (like me - I'm just a
pilot).

Another issue I think recall correctly, was I could find only one
company supplying a ram air parachute that they claimed was suitable for

the "lightly" trained pilot looking for an emergency parachute. I
wasn't
persuaded by what they said on their website that it's advantages were
small and might not actually exceed the disadvantages.

There was puzzling statement on page 235 of Poynters book:

"Round canopies blow up more often, possibly 30% in normal use."

This sounds incredible for certified emergency parachutes, and it makes
me wonder if he is even talking about the same thing I am, where "normal

use" is 20 years as a seat cushion, and very rarely, only one jump in
it's entire service life. My perception is round emergency parachutes
function properly with failure rates far less than 30%.

--
Eric Greenwell - Washington State, USA
* Change "netto" to "net" to email me directly

* Updated! "Transponders in Sailplanes" http://tinyurl.com/y739x4
* New Jan '08 - sections on Mode S, TPAS, ADS-B, Flarm, more

* "A Guide to Self-launching Sailplane Operation" at
www.motorglider.org

At 14:30 09 December 2008, Gregg Ballou wrote:
Smoke jumpers switched to squares. Technology marches on. Rounds are
still the best parachute for those little estes model rockets.

If I go to one of the local jump schools that does static line
jumps for beginners, what sort of chute should I expect?
I did that years (and years and years) ago, about the time
I started flying gliders, and did three static line jumps with
round parachutes that had panels removed to make them
steerable (as I recall). That was at Sky Manor in NJ.

Jim Beckman

On Dec 10, 7:30*am, Jim Beckman wrote:
If I go to one of the local jump schools that does static line
jumps for beginners, what sort of chute should I expect?


You will receive instruction for, and jump, a ram air (square
parachute) and will have, but hopefully not use, a ram air reserve.
That assumes a USA USPA affiliated drop zone. Someone may find a
third world country where they'd give you a round.

Andy

On Dec 10, 6:30*am, Jim Beckman wrote:
At 14:30 09 December 2008, Gregg Ballou wrote:

Smoke jumpers switched to squares. *Technology marches on. *Rounds are
still the best parachute for those little estes model rockets.

If I go to one of the local jump schools that does static line
jumps for beginners, what sort of chute should I expect?
I did that years (and years and years) ago, about the time
I started flying gliders, and did three static line jumps with
round parachutes that had panels removed to make them
steerable (as I recall). *That was at Sky Manor in NJ.

Jim Beckman

Hope it goes better than it did for this guy:
http://news.aol.com/article/skydiver...ot-fall/272955 ,
but then again, he did survive after all...Hmmm, is that good luck or
bad luck. Cause if he were lucky, wouldn't his chute not have gotten
snagged on the jump plane?... But if he were unlucky, wouldn't...

In a vain attempt to maintain thread relevance, I have no idea if his
rig was 20yrs, but I bet it was square. Is a square more likely to get
snagged on your glider :-)

-Paul

I'm having trouble figuring out a couple of things about this story.

One -- why/how did his chute get caught on the jump ship?! That's
almost unheard of. Almost certainly it was an accidental deployment
that probably started inside the airplane when the door was open, or
when he was in the process of climbing out. Regardless, round or
square wouldn't make much difference -- blowing fabric will make its
way around anything.

Two -- there's no mention of his reserve or whether or how he tried to
use it.

Tuno Squarepants

"Tuno" wrote in message
...
Eric,

Poynter's statement was about round parachutes in general, not
reserves, and by 30% he was comparing the malfunction rates to each
other; he did not mean to say that round parachutes malfunctioned 30%
of the time.

I would very like to know who you spoke to in March. Though I am not
surprised that a manufacturer would encourage you to stick with a
round chute -- they make money selling you either kind, and think that
they assume a liability risk if they do anything but tell an
"untrained jumper" to use a round parachute.

The fact is, "square parachutes require training". But consider the
target audiences -- just about anybody can go make a parachute jump.
Licensed glider pilots have a FAR higher general compentency level
than your average yahoo. (At least in Arizona And I can assure you
that operating square *reserve* parachutes is an EASY thing for glider
pilots to do.

2NO

OK--is there a way to get the needed training without jumping from a major
height?
i.e. risking your neck (literally, apparently) to learn to save it, may not
be the ideal equation.

Hartley Falbaum