From: jerrys@umiacs.umd.edu (Jerry Sobieski)
Newsgroups: rec.skydiving
Subject: Re: AAD Question
Date: 6 Apr 92 16:34:54 GMT
Organization: UMIACS, University of Maryland, College Park, MD 20742

In article <2APR199221302350@uhdvx3.dt.uh.edu> 0632cs03@uhdvx3.dt.uh.edu (Andy Calistrat) writes:
>[stuff about Canadian skygods doing something stupid deleted.]
>
>Question:  Does this incident make you more or less likely to use an
>           AAD personally?
>
>

I love a good debate...(:-)

What do YOU think was the problem with the jump?  I don't think it was the 
AADs.  THEY seem to have worked just fine.  I find it very hard to
believe that the 7 Canadian Team jumpers and Norm Kent could have a 
burble problem at 3000' that they could not resolve in 10-12 seconds.  

First, why were they still doing RW at 3000'?  This is below the 
BSR limit for breakoff.  Now, we all know the 3500' breakoof is
routinely ignored by experienced jumpers.  But by doing so, the jumpers
take on an added risk of opening low, or dangerously close to one another.

Secondly, at 3000', what was NK doing upside down underneath a formation?
This IMO was stupid.  Even for Norm, and even for the team.  If Norm was
trying to get a novel shot, they certainly didn't need to be that close to
the ground to get a camera angle towards the sky.

Third, how do 7 world class jumpers in a donut get taken out by a single
burble? Even from a large jumpsuit of a camera man?

Fourth, if these guys lost track of altitude, why?  Don't they have
paralerts or dytters?  Did they ignore them?  I know of no cameraman
who doesn't religously wear an audio altimater.

This article sounds a bit fishy to me.  Particularly when it is a 
*Press Release* from the manufacturer of the AADs.  

IMO, the AADs firing was good in that they worked as promised.  However,
I don't think the publicity for the Canadian Team was something I would
want for MY team.  These guys weren't heroes, they were lucky.

Now...as the the AAD debate...

I think the argument that AADs are more of a risk than the problem
they attempt to solve has been pretty well decided.  AADs can and do
prevent fatalities and the odds of them firing prematurely are almost nil.
The real question each jumper must ask themselves is whether they feel 
they are at greater risk without one or with one. I.e. do you feel
that the odds of finding yourself below 1500 feet in freefall is worth
the cost and maintenance of an AAD.  

I have seen AADs fire prematurely.  Twice.  Once on a level 5 AFF student at
7000', and once on a Level 1 student- under a good main canopy- at about 
1200 feet. Both instances were traced back to improper maintenence where
the device had gotten wet and should have been overhauled.

I have jumped with many rw folks with AADs with NO adverse problems.  The
most frequent problem I have witnessed with experienced jumpers and
AADs, has been when they were taking it too low.  They dumped too close to
the activation altitude.

Student AADs see MUCH more use and abuse that AADs of experienced jumpers.
The DZs are generally pretty good about AADs and their maintenance.
The experienced jumpers I know who use AADs will send them to the factory
once a year (or every other year) for recalibration and testing.  
And I've not seen those units malfunction (Sentinals).

The point I am making here is that AADs are expensive to buy, expensive
to install, and must be maintained correctly and conciensiouly.
Jumpers wearing them must be more cognizant of the altitudes and manuvers
they are doing - i.e. dumping low, crew below 1500 feet, descending in the
aircraft, etc.  But the risk to other jumpers is almost non-existant.

Dale's friend who admonished him for wearing the AAD should be the one
to beware.  He is blaming someone else for a risk he is about to take.
If a jumper has problems with other jumpers who use AADs, that jumper should
not jump with them.  That is commen sense.  I have seen far more reserves
dumped prematurely on jumprun or climbout due to careless movements and external
pins than all the AADs that I've ever seen fired at all.  Like so many other
aspects of jumping (and life in general), it is more likely human
error will cause an accident than mechanical failure of the properly
maintained machine. 

So: Know thy fellow flyer.

Sorry to ramble so...

Jerry

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