>> ...even though Patty, Dale, Dave P, and many others
>> could answer much better...
>
>Not to mention our own Ben Chiu! Thanks for directing us
>to that great article you and Patty wrote on G forces. I
>read it in Sport Aerobatics, but I didn't know you had it
>available on line.
>
>Tom P. I rarely get involved in discussions on this topic but .... There is much good material in Sport Aerobatics magazine. (I was unaware of the online Ground School here - it deserves to be publicised more).
A few of us in Australia have been active in trying to get our local draft Advisory Circular AC 91.075(0) on track. See it at
http://www.casa.gov.au/avreg/newrules/casr/091.htm
It was derived from the USA AC which I believe to be way outdated. AC91-48, from memory at
http://av-info.faa.gov/dst/ACreference/090-099.htm
My friend, Hilton's comment on this subject was posted a couple of years ago - its copied below for info. (Hilton is a medical doctor and former member of the Australian aerobatic team)
Also, this link to a USN powerpoint slideshow is about the latest military word on the subject and seems to be closer to Hilton's view than earlier work.
http://www.nomi.med.navy.mil/NAMI/GTIP.PPT
If you don't have Powerpoint take a peek at Google's html version at
http://216.239.51.100/search?q=cache:yj3mN-XnBHoC:www.nomi.med.navy.mil/NAMI/GTI\
P.PPT+g+TOLERANCE&hl=en&ie=UTF-8
or download Microsoft's free Powerpoint Viewer at
http://office.microsoft.com/downloads/2000/Ppview97.aspx
One of our local universities is undertaking some research on this subject - a "Survey of G-induced visual
and cognitive disturbances in pilots of high-performance aircraft". Australian Aerobatic pilots were requested to take the time to complete the survey. I must check with them and see how they're going.
http://www.flightmed.com.au/
Go to the What's New page then research project.
Finally, I see that Patty has neatly avoided part of the original question.
' it's not very difficult to stay "conscious" '
I believe that we all do as Hilton says, for positive g manoeuvres. For negative g, just try and relax - but watch out for a sudden change to positive g.
Regards,
Dave Pilkington
__________________
From: "Enid Selvey" <enids@ozemail.com.au>
Date: Mon Jan 31, 2000 10:17 pm
Subject: G-loc cont.
David,I am as supportive of CASA going the same way as the FAA as the next man and more so than most with regard to the Experimental Category.
But I won’t support CASA when their advice about +G forces is so obviously wrong! The draft A/C on aerobatics was written, I was told, by laymen. By that I understand that the authors were neither aerobatic pilots nor doctors. This is to me very alarming and absurd and should be so to every pilot in Australia.
The advice given to counter the effects of +G may well be the cause of G-LOC accidents and I urge all pilots in Australia to have none of it.
The correct advice is to take up endurance training and when under G stress contract the lower limb and abdominal muscles and BREATHE AS NORMALLY AS POSSIBLE. DO NOT DO THE VALSALVA MANOEUVRE, THE M MANOEUVRE OR ANY OTHER MANOEUVRE BY WHAT EVER NAME WITH THE EXCEPTION OF THE S MANOEUVRE WHICH CONSISTS OF A RAPID DEEP INHALATION AND A NORMAL EXHALATION IF A-LOC IS EXPERIENCED.
You will notice that this advice is the direct opposite to that given under "conventional wisdom". Conventional wisdom is not synonymous with correct wisdom.
A-LOC is the latest, it stands for almost G-LOC! It is the experience of feeling slightly off as if the world has become unreal, everything slightly out of focus. This feeling is followed by black out if the stick forces are not relieved or the S Manoeuvre is not done.
Regards,
Hilton