"Greg Copeland" wrote in message
news
On Tue, 27 Apr 2004 18:58:11 -0700, C J Campbell wrote:


"Vaughn Simon" wrote in message
The occupants of a Cirrus can hope to "survive" a spin from 900
AGL

How so, if the Cirrus cannot recover from a spin and the parachute needs
more than 900 feet to deploy?

Ya, that's the point I brought up in another subthread here, which went
unanswered. Maybe you can help.

If the deployment requires 920, does that mean after 920 you can safely
touchdown or does that mean it requires 920 + however long it takes to
slow your velocity to proper touchdown velocity? I ask because, I don't
think a chute opening 10 AGL is going to help much.

I believe the POH says that is the altitude necessary to safely touch down.
Whether it could be of any help before that I don't know. Even partially
opened the parachute is going to add some drag, but what happens is that the
parachute is pulled out by a rocket. Instead of opening instantly (which
would destroy the chute) a Teflon coated ring slides down the shroud lines
to allow the chute to open in a controlled manner. The airplane continues
moving forward during all this process. Once the chute is opened, the
airplane swings down under the canopy. So dropping that last few feet just
as the parachute opens the airplane's rate of descent might not be slowed at
all.

All of that assumes that the airplane is in normal forward flight. The
Cirrus spins in a flat attitude and it might not have all that much forward
motion. I guess the actual altitude needed would vary some depending on just
what the airplane is doing at the time the CAPS system is deployed.