Phil,


You are mostly correct, but the critical thing in deployment is the time factor and hand deploy cannot match ballistic ejection.


I feel I am somewhat qualified to comment, I survived an inflight catastrophic failure, and hand deployed. It is 4 to10 seconds to get a hand deploy out, my spinning glider was wrapping up the bridle and shroud lines faster than the chute was deploying. It never had time to inflate.


The weight to deployment time ratio makes a rocket well worth the extra weight of a positive deployment device.


Russ how well do you throw a parachute spinning amid the wreckage? All the practice in the world will not prepare you for the event, but your body will go through the motions, the question is will it clear the wreckage and inflate in time? At 60 miles an hour 10 seconds eats up 880 ft of altitude. With a rocket you lose 88 ft before line stretch and canopy opening.


Regards,


One Sky Dog
Charlie Johnson
Ogden, Utah

Sent from my iPad

On Dec 20, 2012, at 4:05 AM, "Philip Lardner" <This email address is being protected from spambots. You need JavaScript enabled to view it.> wrote:


2 Videos - www.ihpa.ie/carbon-dragon/index.php/videos Coup Icare 2010 - Archaeopteryx breaks up in loop.
BTW - the pilot admitted exceeding both Vne and the max G-loading when this glider broke up - it's still a perfectly safe design.

Take a look at just how fast the Archaeopteryx spins around after it disintegrates after exiting that loop and tell me you'd have the presence of mind (let alone the strength to overcome the G-forces involved) first to release the canopy and then remove your hand-deployed parachute from its container, look for a clear spot and throw it. I don't think so! Give me a 'fire and forget' rocket deployed 'chute any day.

During our hang gliding parachute repack sessions, pilots are suspended in their flight harnesses from a roof beam in a sports hall and swung vigorously from side to side of the hall. When they have built up enough speed someone steps in and spins them around by the feet at high speed to simulate the disorientation and G-force involved in a HG break up. The pilot's arms, which start out in the normal bar position for flying, are flung out straight by the G-force, which he then has to overcome to first locate and then to deploy his reserve parachute. It's not an easy task - and nothing like as difficult as a real emergency deployment under a high G spin that pilots have reported following their gliders breaking up (usually due to them flying beyond Vne in rough air during competitions.)

The Swift Lite and Archaeopteryx both use ballistic reserve deployment systems, as does Yasushi Akahori in his own Carbon Dragon - www.ihpa.ie/carbon-dragon/index.php/cd-b...yasushi-akahori-s-cd.

Phil.

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From: This email address is being protected from spambots. You need JavaScript enabled to view it. [This email address is being protected from spambots. You need JavaScript enabled to view it.] On Behalf Of russell wilson
Sent: 20 December 2012 01:09
To: This email address is being protected from spambots. You need JavaScript enabled to view it.
Subject: Re: [Carbondragonbuildersandpilots] Re: 3 Piece Wing



i belive balistic reserve is too heavy for this aircraft,i recomend a hand thrown reserve.
...

the arkopterex has failed doing airobatics,there are real stories of sailplanes being broken up in rotor tubulance.