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Ahhhh...25 feet per
SECOND is not 1,500 feet per MINUTE? What am I missing
here?
1) You are
absolutely right that starting in a Cirrus is not a good idea. The
150/172 approach is much better.
2) You are absolutely wrong,
however, in your characterization of the BRS. They are not designed to
lower the airplane at 1500 fpm, looking for a steep slope in order to
survive. The weight rating on those puppies is that weight
resulting in a 25 foot-per-second descent rate at an altitude of 5000
feet. I know this because last month I was in a telephone conference
with the two senior engineers at BRS. We were asking whether a light
sport amphibious airplane (1430 pounds) could use their chute intended for
land-based light sport airplanes (1320 pounds). This is when they
described how they rate the chutes. With our higher weight, we would
have a descent rate of 25.7 fps, which might be acceptable if other
impact-attenuation devices were used (such as crushable seats) but we'd have
to convince them of the survivability at this higher descent rate first.
3) You are absolutely correct that a last-ditch parachute system
which depends on having enough controllability to slow to 165 KIAS is a pretty
foolish and useless concept -- unusable unless maybe you're on fire over the
mountains. Myself, I don't believe in BRS's at all, but then I didn't
believe in air bags either until I head-on collision with a teenager driving
on the wrong side of the road last year. (70 mph rate of closure and me
in a Miata. I walked away. Maybe them things are useful after
all...)
And no, there's no farmer's daughter in this story
either...sorry!
- Rob Wolf
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