curl@wjvax.UUCP (Jim Curl) (10/05/85)
I am fairly new to this sport (16 jumps) and was surprised to read in
this group about a non-static-line method of initial training in parachuting.
The method described seemed to me to be somewhat more dangerous than the
traditional static-line approach.
After reading about it, I came across this note in the October issue of
Parachutist magazine that I thought might be of interest to readers of this
group:
DEPLOYMENT TEST ENDED
The Palatka Parachute Center in Forida terminated its
experiment with jumpmaster assisted deployments for student
jumpers recently after a student trapped a pilot chute and
held it until the automatic activation device deployed at
about 1,000 feet. DZ owner/operator Don Yahrling had been
conducting the program under a waiver to the Basic Safety
Regulations from the USPA Safety and Training Committee.
The jumpmaster assist method involves the jumpmaster
extracting the student's hand-deploy pilot chute before
climb-out and deploying it immediately after exit. The
method is especially popular in Canada but is employed at
very few U.S. DZs.
( Jim Curl )
( San Jose, CA )kas@hp-pcd.UUCP (kas) (10/10/85)
> DEPLOYMENT TEST ENDED > The Palatka Parachute Center in Forida terminated its > experiment with jumpmaster assisted deployments for student > jumpers recently after a student trapped a pilot chute and > held it until the automatic activation device deployed at > about 1,000 feet. DZ owner/operator Don Yahrling had been > conducting the program under a waiver to the Basic Safety > Regulations from the USPA Safety and Training Committee. > The jumpmaster assist method involves the jumpmaster > extracting the student's hand-deploy pilot chute before > climb-out and deploying it immediately after exit. The > method is especially popular in Canada but is employed at > very few U.S. DZs. Ever since this subject got started, I've had a few nervous thoughts about it. The above article has justified my fears. While no mechanical system can ever be made 100% fail-proof, I've always thought that static lines came pretty close, in terms of positive deployment. Granted, the static line system as a whole has other undesirable traits, and for this reason I'm a strong believer in the AFF system. But quite frankly, I don't consider the jumpmaster assisted deployment to be an improvement over static lines. An additional problem that I predict will occur (if it hasn't already), is the pilot chute snagging on some portion of the aircrafts' anatomy, such as a tail wheel. If the jumpmaster releases his grip before there is a sufficient load on the bridle line, that pilot chute is going to get whipped by the prop-blast straight back into the tail feathers of the airplane. I once saw this happen when a static line broke loose prematurely, and the apex of the canopy snagged the tail wheel. Fortunately, the jumper-in-tow (a first time jumper, no less), had the presence of mind to execute a cut- away and deploy his reserve. If he had panicked and dumped his reserve first, the results would have been catastrophic. The easy cure for this problem was to use a stronger tie cord on the end of the static line. There is no easy fool-proof cure for the jumpmaster assist method. Another potential problem might be accidental release of the pilot chute in the aircraft, the results of which we're all too familiar with. This can't happen with static lines. I can understand the desire of both students and instructors who want to use "state of the art" equipment, rather than old military surplus gear. It eliminates the uncertainty of transitioning from one type of gear to another. The advantage to the jumpmaster assist method is that the student uses the same rig (or one just like it) for his first jump as well as his first freefall. I propose that this can still be accomplished by removing the pilot chute and attaching a static line for the first few jumps, and then replacing the pilot chute when it's time for the first freefall. Attaching a pilot chute is a 30-second job for a rigger who knows how to do it, so it's no big hassle. The bridle and/or static line can be secured with rubber bands or velcro loops to provide enough resistance to prevent premature pack opening until the jumper is safely below the aircraft. Thus, with proper rigging, all the problems mentioned above are eliminated, and the advantage of positive deployment is gained. So, all you jumpers/jumpmasters/instructors/riggers out there who are using the jumpmaster assist method, what do you think? Have I overlooked some major issues? If not, consider making, or recommending, the changes. * / \ |---/---\---| Ken Scofield C-9355 | Gone | Hewlett-Packard PCD | Jumpin' | Corvallis, OR |-----------| {ucbvax!hplabs, harpo, ogcvax}!hp-pcd!kas
brent@poseidon.UUCP (Brent P. Callaghan) (10/16/85)
I think the issue of the student trapping the pilot chute
is rather a red herring. There are many accident reports
already for static-line assisted pilot chutes being
trapped by the student after a poor exit.
I can see the rationale behind the jumpmaster assisted
deployment. Almost any hand-deploy rig would be suitable
and no special mods or preparation required. Static
lines are a hassle. You have to be sooo careful to check
that the hardpoint attachment is secure. Unless you want
a mess of S/Ls all over the floor you attach the static
line just before jump run for each student. That's
what I used to do. Less popped rigs that way. A fellow
jumpmaster had enormous guilt feelings when he once forgot
to check the attachment and totalled the student's main!
Also there is the fear of static-line hang-ups.
Despite all the above, I agree with Ken Scofield's comments.
I would MUCH rather have a static line flapping around in
the aircraft (and the attendant hassle) rather than a
pilot chute. There is a significant risk of the pilot
chute snagging the tail. We had an accident some time ago
where a student popped his rig in the door of a Cherokee Six.
The pilot chute went over the stabilizer as he fell away.
At line stretch the pilot chute was pulled free, but it
bent the stabilizer down at almost a 90 degree angle as
it came off. The aircraft entered a spiral dive with the
pitch controls jammed. The rest of the load exited before
the Gs became too much. The pilot managed to pull out of
the dive by winding full up-trim and landed using engine
power to control pitch. Wow!
--
Made in New Zealand --> Brent Callaghan
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