wrote in message news:
G-LOC= "G force induced loss of consciousness" There's a fairly linear
relationship between time spent at positive Gs and loss of consciousness
for
any individual. (Vector pointing straight down or parallel to the
spine.)

The graphs at the site linked below are far from linear!

At any particular g load.

As another example, I just realized my kids pull more than 2 G's
every day on the swings (although a sub-second timeframe may not meet
my definition of "sustained" :-).

Five seconds is "sustained".

OK. What happens at timescales significantly above 5s?

Sleep.
http://aeromedical.org/Articles/g-loc.html


What is the baseline in the graph at the site? 0g or 1g? Note that
level flight is 1g, of course.

1G

It is mentioned that G-LOC has happened with as little as 2g. This
would mean 60 degree banking turn. I think even airliners allow more -
like, IIRC, Airbus flight envelope protection extends to 67 degrees.
What is the corresponding +g load?

About 3Gs.

And I suspect that this G-LOC at +3, +4, +2 concern pilots sitting and
staying seated in a pilot seat. Thighs horizontal, buttocks supported,
back somewhat supported (reclining enough not to slump forward or aside
on G-LOC). Right?

At which g would one suffer G-LOC while standing up in an aisle?
Walking along aisle?

At which g can one feel safe to get up suddenly and put a heavy item in
an overhead bin? Go and use a lavatory?

It really depends on the individual. Almost anyone can tolerate 2Gs for a
sustained period but moving about or lifting anything heavy would be
difficult. I think that the cutoff point for the average person (sustained)
is around 3.5Gs.


What would be the effect of 2g sustained for 5 minutes? Or for 5 hours?
I mean, I suppose circling at 60 degrees bank angle would be somewhat
wasteful of fuel, but the airliners do manage 18-19 hours level flight
nonstop and without tanking...

Over 30 degrees of bank angle is unusual for an airliner. If you're not
used to it, 60 degrees looks and feels like 90.

Can one sleep (and get up again) at 2g?

That's an interesting question. xposted for an answer.

moo