In message <001301c1acff$6b2af5a0$a1a81e3e@adrian>, Adrian Fogarty
<[log in to unmask]> writes
> The g-forces must have been considerable, 60 to 0 in less
>than a second. That's probably around 4 or 5G I think (any mathematicians out
>there?). I've never been sure if such blackouts represent a pure neurological
>phenomenon, i.e. concussion, or merely a cessation/redistribution of blood
>supply, i.e. a type of cerebral "syncope". Anyway, I agree with Duncan; such
>blackouts are pretty innocuous. I had no neurological symptoms or sequelae of
>any kind.
>
60 to 0 in less than a second is a lot more than 4 or 5G. My aircraft is
stressed to +6/-3 and it is not as battered as your motor would have
been, and I do like to fly the arse off it!
60 mph is a very credible survivable crash (and landing) speed in an
aircraft if you slow it down enough (recommended technique). Data in the
aviation medicine literature shows deceleration of 48G peak and 24 G
mean over 0.054sec in a surviveable accident. Ouch!
>
> In motorsport medicine where you can get to motorcyclists within 60 to 90
>seconds of the accident, there are a number who have a high delta v, or change
>in velocity that are unconscious when you get to them. With airway support and
>some oxygen, they come round and are neurologically "normal" in a minute or two.
> Full assessment can fail to reveal any external evidence of head injury
> These people obviously have some transient brain malfunction and are "knocked
>out".
I went up and seriously mishandled a manoeuvre last weekend. I started
to grey out. There is no question of me hitting my head. It was
'orrible.
If a motorcyclist decelerates or accelerates abruptly, then I have no
doubt that cerebral bloodflow is transiently interrupted. If the head is
not struck, the insult is perfusional rather than traumatic. It is
rapidly reversible. That is, I believe, what Duncan is pointing out and
I must say that I agree with him.
>
> ----- Original Message -----
> From: Adrian Kerner
> Sent: 02 February 2002 22:43
> To: [log in to unmask]
> Subject: Re: Grey out
>
> Andy - I like the tem 'grey out'!
>
> Regards
>
> Adrian
>
Forget it. It feels like Sh*te!
>
--
Stephen Hughes SpR Aerobatics and Everything.
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