On Sep 6, 2009, at 11:48 AM, Brian Mury wrote: > Nate, > > On Fri, 2009-09-04 at 09:39 -0600, Nate Duehr wrote: > > > We (AF6IM and KF6WRW) have been keeping our toggles stowed until > we > > > get to about 3000 ft. > > > > If you pulled at 3000' MSL here, well... you'd be dead/underground! > > 1. Unlike pilots, skydivers always use AGL, not MSL. When we are > headed > straight at the ground at 120 mph (or possibly a lot more depending on > body position), we really want to know how far away the ground is > without having to remember and subtract the ground elevation. Since we > almost always land at the same location we took off from, and are > not in > the air long enough to worry about significant barometric pressure > changes, it makes sense to use AGL.
Ah, gotcha. > 2. When Mark says "keeping our toggles stowed", he is not talking > about > deploying the parachute. The toggles are the steering controls. > Parachutes are packed with them locked partway down in order to > improve > the deployment. Once the canopy is open, the jumper releases the > toggles > to allow the canopy to go to full flight. Leaving them stowed will > result in slower flight and a lower descent rate, useful to give Mark > more time to play with the radio, as well as reducing wind noise that > the mic will pick up. Fascinating, I never knew that. Thanks. -- Nate Duehr [email protected] facebook.com/denverpilot twitter.com/denverpilot
