A further thought I remember a photo(I think it was US ridge runner Karl Striedeck) this pilot had a 3" thick piece of fairly high density foam attached to the top of his hat for just this reason!
Game eh? Regards Dav ----- Original Message ----- From: "Simon Hackett" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Monday, July 29, 2002 5:27 PM Subject: Re: [aus-soaring] Many thanks to everyone > Its interesting just how much your head can 'rise' through some form > of in-flight turbulence. If you think about how (relatively) flexible > your neck can be in that axis, and how (relatively) heavy an object > your head is, it isn't hard to see the issue :) > > I've cracked the canopy on a Libelle some years back while ridge soaring in it. > > I know I had the canopy straps tight as they'd go - I had sinched > them down due to the level of turbulence encountered earlier in the > flight, and had even mentioned that on the radio to my colleagues on > the ridge as well by way of warning to them as well... and then, > seconds later, I ran into a patch of air that felt like hitting a > wall. > > Next thing was the loud sound of rushing air, from what (in my case) > had been a 'shoulder to shoulder' crack in the canopy - literally > from the frame by my left shoulder, all the way over the top to the > same spot on the right. > > I just curtailed the flight (obviously!) and landed normally (other > than it being somewhat louder than normal, and other than my flying > at the lower end of the safe speed envelope to avoid further damage > if possible). > > What it has done for me is made me aware that what we might normally > consider to be 'sufficient' clearance between the top of the noggin > and the canopy 'roof' may in fact not be sufficient clearance after > all - in the case of my own physical dimensions and those of a > libelle, I basically have trouble squeezing in under there with what > I consider 'enough' clearance to be comfortable about the issue - > especially after the incident noted above. > > Also, and perhaps worthy of mention, I believe (its all a long time > back, now) that the cap I was wearing at the time was a 'baseball' > cap of the sort that has a 'button' at 'top dead center' on the top > of the cap. I suspect that button functioned in a manner similar to > the sharp end of a chisel, and cracked the canopy rather than > distributing the impact load more widely (meaning the canopy might > not have broken otherwise). > > So it might be worth thinking about avoiding the use of that sort of > cap if you plan to fly while jammed right in under the perspex > without any clearance :) > > Even worse in some ways is the notion of your head jammed in just > under the canopy or cockpit -frame- of a glider, not under the > perspex - in a jolt sufficient to stretch your neck and head up > through the canopy and break it, think about the belt to the brain > you'd get if you hit the frame instead of the (relatively flexible) > perspex. > > Must be a serious potential there to get knocked out by that turn of > events, which is all rather less than fun to contemplate. > > It is a reminder, to us all, of just how much kinetic energy we're > working with inside the normal flight speed envelope, and how easily > it can be turned into an unexpected outcome by factors external to > the aircraft. > > Regards, > Simon > -- > > > Simon Hackett, Technical Director, Internode Systems Pty Ltd > 31 York St [PO Box 284, Rundle Mall], Adelaide, SA 5000 Australia > Email: [EMAIL PROTECTED] Web: http://www.internode.on.net > Phone: +61-8-8223-2999 Fax: +61-8-8223-1777 > > -- > * You are subscribed to the aus-soaring mailing list. > * To Unsubscribe: send email to [EMAIL PROTECTED] > * with "unsubscribe aus-soaring" in the body of the message > * or with "help" in the body of the message for more information. > -- * You are subscribed to the aus-soaring mailing list. * To Unsubscribe: send email to [EMAIL PROTECTED] * with "unsubscribe aus-soaring" in the body of the message * or with "help" in the body of the message for more information.
