BRS Question

This is way more engineering than I can deal with, but it seems there could
be a way to gradually increase airspeed over the control surfaces before
cutting the chute loose, in the same way air is spilled from a chute to
control direction. Maybe a vent that opens in the chute - all theory,
anyway...

Michael



"G.R. Patterson III" wrote in message
...


Michael 182 wrote:

I'm thinking about floating down in a $400K Cirrus with chute deployed
in a
spin in IMC, then breaking out at 1500 feet looking at a suitable
landing
place and cursing the imminent destruction of the plane.

Well, you're not traveling forward anymore, and you have less than a
minute to cut
the chute loose and dive the plane enough to get enough forward speed to
get flying
again. With no airflow over the control surfaces. Doesn't sound real
feasible to me.

George Patterson
If you don't tell lies, you never have to remember what you said.

"Michael 182" wrote in message
news:f0hjc.43581$IW1.2174699@attbi_s52...
This is way more engineering than I can deal with, but it seems there
could
be a way to gradually increase airspeed over the control surfaces before
cutting the chute loose, in the same way air is spilled from a chute to
control direction. Maybe a vent that opens in the chute

The parachute used in the BRS isn't anything like the sport parachutes that
provide directional control and forward momentum. It's a basic round
parachute, designed to eliminate the airplane's forward momentum and then
allow it to descend vertically to a survivable landing. It would require a
complete redesign of the BRS, and would greatly add to the complexity.
Complexity is a bad thing in general (though is often unavoidable), and in
an emergency safety feature is to be avoided at all costs, IMHO.

Besides, even if you could theoretically design a parachute that provided
for a straight-down vertical descent, while at the same time being
convertible to something like a sport parachute, you'd be hard-pressed to
increase the forward speed to anything even close to the stall speed for the
airplane. Ten or twenty knots max, is my guess and then you'd still have
the same issue, with the airplane detaching from the parachute in a steep
nose-down configuration until it gained enough airspeed to actually glide.

The current system is nice and simple, giving the pilot no options once the
decision to pull the cord is made. The system you're proposing allows the
pilot to turn what should almost always be a survivable landing into a
potentially deadly situation, and significantly increases the overall
complexity of the system at the same time. I just can't see how that's a
good idea.

If you *really* want to be able to let go of the parachute, I'd say install
some sort of rocket canisters to the airframe. When you want to detach from
the parachute, you hit a button that ignites the rockets, and before the
pitch attitude gets dragged too high by the parachute dragging behind, the
system automatically detaches the parachute, leaving you in a
soon-to-be-unpowered rocket-propelled airplane.

But that solution, even if I think it's superior to the one you propose, is
still fraught with problems.

Pete

"Peter Duniho" wrote in message
...
"Michael 182" wrote in message
news:f0hjc.43581$IW1.2174699@attbi_s52...

If you *really* want to be able to let go of the parachute, I'd say
install
some sort of rocket canisters to the airframe. When you want to detach
from
the parachute, you hit a button that ignites the rockets, and before the
pitch attitude gets dragged too high by the parachute dragging behind, the
system automatically detaches the parachute, leaving you in a
soon-to-be-unpowered rocket-propelled airplane.

Hey, I like this idea. Always wanted a rocket powered 182...