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Old February 12th 04, 02:02 PM
Jim Harper
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Mike Borgelt wrote in message . ..
snip
I once saw a movie of the BRS drop test on a C150 simulating its
arrival under a deployed BRS chute. I doubt that the Cessna was
useable again even though it was a symmetrical level attitude when it
hit with no drift. I'd hate to hit at a similar descent rate in a
glider. In Oz we've had a few people do hard landings in the last
couple of years. Some are considered lucky to be walking but the
gliders are repairable. Air bags may be essential.


Of course I would expect that the glider wouldn't be reusable after
using the BRS...I would only pull the thing is a situation that would
lead to me leaving the airplane, should I have had a parachute. In
that case, the airplane is a write-off. As I have previously
recounted, I have the thing set up to lower the airplane nose down
somewhat...one hopes that the forces will be somewhat dissipated by
the landing attitude. Of course the risk of injury exists for a
successful bail-out as well. It's interesting that in this dialogue
folks worry about hitting under canopy IN the glider, and don't
discuss the myriad of risks associated with hitting under canopy OUT
of the glider.

I parachuted in the military and in sport. I have seen more than a few
broken bones, broken backs, internal injuries and others. And those
were with trained parachutists jumping under controlled situations and
the best possible conditions, with prepared...or at least
planned...drop-zones. I don't think that to be the case for the
typical emergency bail-out from a broken glider.

We've had this debate on this board more than once and in each case,
it seems to me that we set a double standard...somehow we assume that
the guy who leaves the glider and deploys a round canopy for his first
parachute jump ever will arrive on the ground unscathed...and the guy
who pulls the BRS lever is subjecting himself to an extraordinary
amount of risk, because he _might_ hit the ground in a manner that
_might_ lead to injury.

The reality is that when the decision to deploy either your personal
canopy OR the BRS is made, your only other option is very likely
death. If I can fly the airplane, I am going to fly the airplane. If
my airplane is damaged beyond the point that I can fly it, I am going
to deploy. If when I land I am injured, I still firmly believe that I
am going to be far better off than if I had ridden the glider to the
ground without a parachute. And no question...if I had room in the
cockpit/no weight constraints, I would ALSO wear a square emergency
parachute for those cases where I AM high enough to choose that
egress. I think that I would STILL have the BRS, though, for the
collision in the pattern or the like. And I have far more experience
under a parachute canopy than 99% of glider pilots.


Are your gliding club members smart enough to avoid inadvertent
deployment of a ballistic chute in the hangar? At one club I used to
belong to the new ASW20B got wheeled up twice in a month or so - in
the hangar as people said "what does this lever do?". In the chute
case you would hope nobody else was standing behind the wing looking
into the cockpit.


The BRS system has a remove before flight safety pin. With the pin in
place, the BRS cannot be deployed. If some yahoo starts playing with
my glider and REMOVES the safety tag/pin and then pulls the handle? I
would, under those circumstances, hope he DOES have his face in front
of it. He will certainly have exceeded any reasonable "what does THIS
lever do" level of curiosity in my book.

About 12 years ago we did a precision altimeter project for an RAAF
test project. The chief aero engineer of the research and development
unit was building an ultralight of his own design. I asked if he was
fitting a BRS chute. He said he was designing the aircraft basically
to high enough standards that like a FAR 23 power plane it was
reliable enough in its structure and control systems that flying
without a chute was a good risk. His opinion was that the whole ship
chutes at the time couldn't meet their claimed descent rates with the
chute sizes used. His first job had been with a parachute manufacturer
so I had to take some notice of his opinion.

Mike Borgelt


One hopes one's glider isn't going to go poof in flight. However,
certificated gliders HAVE gone poof in flight. Further, our sport has
a much higher (at least theoretical) risk of collision in the air than
the usual spam-can. My glider is better built than most of them out
there, and I don't carry the BRS in expectation of a wing
spontaneously folding up. Nor do I plan on running into someone in a
gaggle. But if it happens, I am comforted in knowing that it's there.

BRS parachutes DO meet their claimed descent rates. Look at their
data. They have tested these things extensively. I would suggest that
an aero engineer who had worked for a parachute manufacturer may have
had a bias just like any other fellow...and that WAS 12 years ago. I
guess that if you are making a decision based on one person's opinion
during the last millenium, no matter how experienced, well, more power
to you. I prefer doing a bit more research than that. Once again, with
all due respect, and no offense intended.

Jim