O2 and Cypriot airliner crash

"Bob Moore" wrote in message

My thoughts on yesterday's accident.

My thoughts were tending in the same direction, Bob. Speculation on the
availability of O2, or the system integrity, is fine, but the first and most
obvious question to me was as to why the airplane was still at altitude.
Job 1, superceding all others, is to get the craft to breathable air. What
was going on? All it takes is one body in the cockpit to initiate the
descent.

JG

George Patterson wrote:
Shawn wrote:


You should check Bruce's Lat/Long in his sig before you start quoting
him US FARs.


My original post stated that "the FAA requires that a pilot use oxygen
if they spend over 30 minutes above 12,500'." He said that was wrong.
Doesn't matter where he happens to live, the FAA *still* requires that a
pilot use oxygen if they spend over 30 minutes above 12,500'.

Guess you read it differently than me. I read it as him stating his
experience, rather than correcting you. Usenet you know, it happens.
I know you're correct re the U.S. regs (unless they've changed since
April). I suspect Bruce is correct re the NZ regs given his previous
posting history on ras.
Both sets are really irrelevant in this case. Greek regs would apply.

George Patterson
Give a person a fish and you feed him for a day; teach a person to
use the Internet and he won't bother you for weeks.

That's funny.

Shawn

In article ecxMe.681$wb.595@trndny09,
George Patterson wrote:

Bruce Hoult wrote:

I don't see a section 91.211 in the New Zealand regulations.

I didn't say there was. *You* said the FAA didn't have this requirement.

I did not mention the FAA at all. I mentioned the training I received.

--
Bruce | 41.1670S | \ spoken | -+-
Hoult | 174.8263E | /\ here. | ----------O----------

"Bruce Hoult" wrote in message
...

I did not mention the FAA at all. I mentioned the training I received.


Yes, in response to a comment on the FAA requirement.

The pilots do not have drop down masks and separate O2 system designed
to last at least twice as long as the passengers.
Michelle

wrote:

In accounts of the crash of the Cypriot airliner in Greece, all I've
read say that loss of cabin pressure could not, by itself, incapacitate
the pilot. Yet, I was once told by an ATP that at 40k feet (admittedly
this plane was at 35k) O2 supply by itself will not suffice to keep you
conscious and that the drop down masks only give a false sense of
security. He said that the ambient pressure is so low that even 100% O2
does not provide enough to keep you conscious without a pressure
breathing mask. If he's right, that could explain the crash, especially
given that all it would take is 20 seconds of distraction (i.e., not
donning the mask) to knock out the pilot as indicated in the table
below. On the other hand, I checked and a standard atmosphere at 35k
feet is 7.0 in of Hg, which is more than the partial pressure of O2 at
sea level (6 in = 20% of 30 inches), which would seem to contradict the
info given by the ATP. Any thoughts or corrections to my reasoning?


Tlme of useful
consciousness
Altitude (ft) without oxygen

40,000 15 seconds
35.000 20 seconds
30,000 30 seconds
28,000 1 minute
26,000 2 minutes
24,000 3 minutes
22,000 6 minutes
20,000 10 minutes
15.000 Indefinite

For those who want to read about the medical aspects of Hypoxia, see United
States Naval Flight Surgeon's Manual: Third Edition 1991: Chapter 1:
Physiology of Flight, http://www.vnh.org/FSManual/01/03Hypoxia.html .

Also, have a look at Dr. Daniel L. Johnson's web site
http://amygdala.danlj.org/~danlj/Avi...ine/index.html .

For those who want to read about actual incidents of hypoxia which did not
lead to an accident, see:

Boeing 737 Incident 98.08.13 Report June 99:
http://www.aaib.gov.uk/cms_resources...pdf_501410.pdf

Jet Provost Incident 02.08.18 Report Aug. 03:
http://www.aaib.gov.uk/cms_resources...pdf_023414.pdf

W.J. (Bill) Dean (U.K.).
Remove "ic" to reply.


wrote in message
oups.com...

In accounts of the crash of the Cypriot airliner in Greece, all I've
read say that loss of cabin pressure could not, by itself, incapacitate
the pilot. Yet, I was once told by an ATP that at 40k feet (admittedly
this plane was at 35k) O2 supply by itself will not suffice to keep you
conscious and that the drop down masks only give a false sense of
security. He said that the ambient pressure is so low that even 100% O2
does not provide enough to keep you conscious without a pressure
breathing mask. If he's right, that could explain the crash, especially
given that all it would take is 20 seconds of distraction (i.e., not
donning the mask) to knock out the pilot as indicated in the table
below. On the other hand, I checked and a standard atmosphere at 35k
feet is 7.0 in of Hg, which is more than the partial pressure of O2 at
sea level (6 in = 20% of 30 inches), which would seem to contradict the
info given by the ATP. Any thoughts or corrections to my reasoning?


Tlme of useful
consciousness
Altitude (ft) without oxygen

40,000 15 seconds
35.000 20 seconds
30,000 30 seconds
28,000 1 minute
26,000 2 minutes
24,000 3 minutes
22,000 6 minutes
20,000 10 minutes
15.000 Indefinite

The chart is for time of USEFUL consciousness. The part where the pilot
starts thinking "I feel really great. Look how beautiful the scenery is.
The cold is my friend...." isn't useful consciousness.
"Bucky" wrote in message
oups.com...
wrote:
40,000 15 seconds
35.000 20 seconds
30,000 30 seconds

I don't get it. Can't a person stay conscious for longer than 30
seconds without breathing? Most people can hold their breath for over
a minute.

In article et,
"Steven P. McNicoll" wrote:

"Bruce Hoult" wrote in message
...

I did not mention the FAA at all. I mentioned the training I received.


Yes, in response to a comment on the FAA requirement.

Yes, pointing out that altitudes and durations where oxygen is required
are, like automobile speed limits, is not a hard and fast
physically-significant thing but rathe a matter of someone's opinion,
and that opinions differ in different places.

--
Bruce | 41.1670S | \ spoken | -+-
Hoult | 174.8263E | /\ here. | ----------O----------

"Bruce Hoult" wrote in message
...

Yes, pointing out that altitudes and durations where oxygen is required
are, like automobile speed limits, is not a hard and fast
physically-significant thing but rathe a matter of someone's opinion,
and that opinions differ in different places.


I was just pointing out that you had mentioned the FAA.