What's minimum safe O2 level?

On Mon, 8 Nov 2004 11:31:46 -0500, "Icebound"
wrote:

It was a rhetorical question. The real question was:
Why would you want to fly for 3.5 hours at the edge of a condition which the
FARs state is only safe for 30 minutes or less? Since, technically, it
might not have been a violation if the altimeter setting was more than
29.92, I can see stretching it a bit... maybe 45 minutes or an hour. But
3.5???

Well, the way you initially phrased it was as a potential violation, which
it is not.

OTOH, there are many ways to be legal and not safe (as well as ways to be
safe but not legal). So, for me, anyway, I look at the two separately, and
I don't try to equate one with the other.

For example, flying for 3.5 at 12,500 is probably less safe than doing it
with oxygen. Especially for a sea level dweller who smokes 2 packs of
cigarettes/day. --Legal but not safe--

OTOH, someone who was born and bred and lived most all his life in
Leadville, CO, could probably fly with no problem (and no oxygen) at
13,000' all day long --Safe but not legal--




Ron (EPM) (N5843Q, Mooney M20E) (CP, ASEL, ASES, IA)

"Ron Rosenfeld" wrote in message
...
On Mon, 8 Nov 2004 11:31:46 -0500, "Icebound"
wrote:

It was a rhetorical question. The real question was:
Why would you want to fly for 3.5 hours at the edge of a condition which
the
FARs state is only safe for 30 minutes or less? Since, technically, it
might not have been a violation if the altimeter setting was more than
29.92, I can see stretching it a bit... maybe 45 minutes or an hour. But
3.5???

Well, the way you initially phrased it was as a potential violation, which
it is not.

Well, to be precise, we do not know whether it was a violation or not.

If he was 12,500 indicated, for the whole 3.5 hours, and the actual
altimeter setting was less than 29.92 along more that 30 minutes of the
route, then the "pressure altitude" would have been higher than 12,500 in
that portion, and it *would* be a violation. If the actual altimeter
setting was at or above 29.92 then it would *not* be a violation.

On Mon, 8 Nov 2004 19:28:20 -0500, "Icebound"
wrote:

Well, to be precise, we do not know whether it was a violation or not.

If he was 12,500 indicated, for the whole 3.5 hours, and the actual
altimeter setting was less than 29.92 along more that 30 minutes of the
route, then the "pressure altitude" would have been higher than 12,500 in
that portion, and it *would* be a violation. If the actual altimeter
setting was at or above 29.92 then it would *not* be a violation.


In either case, it would either be or not be a violation. I still don't
know what you mean by a "borderline" violation is.

I would always assume that, without information to the contrary, the pilot
was operating legally.

As I mentioned before, this does not imply that the operation was safe.


Ron (EPM) (N5843Q, Mooney M20E) (CP, ASEL, ASES, IA)