No O2
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From: On a good day - at sea
Ok I'm really puzzled why so many would continue to destination.
You're not legal (airworthy).
And, How can you possibly continue to dest'n knowing how seriously crew performance would be reduced in a real smoke emergency? You're betting it won't happen?
(We had three of these last year in one particular fleet in the span of two or three weeks before determining what the problem was. All three were immediate diversions and not a single eyebrow was directed toward the crew.)
You're not legal (airworthy).
And, How can you possibly continue to dest'n knowing how seriously crew performance would be reduced in a real smoke emergency? You're betting it won't happen?
(We had three of these last year in one particular fleet in the span of two or three weeks before determining what the problem was. All three were immediate diversions and not a single eyebrow was directed toward the crew.)
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From: Planet Earth
Sir Richard, point taken!
nnc0, can you give us more details about actions taken by the crews, did they descend, bring portable O's to the flight deck, try the system to verify the indication etc? 
(We had three of these last year in one particular fleet in the span of two or three weeks before determining what the problem was. All three were immediate diversions and not a single eyebrow was directed toward the crew.)
Today 05:58
Today 05:58
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From: Seattle
You're not legal (airworthy).
Any time you are in a configuration not permitted by the MEL/DDPG, I suppose the airplane is technically "not airworthy" (there was an interesting discussion over the past 2 months in AOPA Pilot magazine by the association lawyer on the issue, and there is NO "black & white"...). However, there are a plethora of such configurations that, even though they would not permit takeoff, do not require an immediate or "as soon as possible" landing. Did the BA pilot who flew on 3 engines from LAX to Manchester (because he ran low on fuel and couldn't make LHR) have a 3-engine ferry permit? Was he "not legal"?
This is what our 747 Classic Flight Handbook has to say on the issue:
There are some situations which always require landing at the nearest suitable airport. These situations include, but are not limited to, wheel well fire, cabin smoke or fire which persists, lower cargo compartment fire, main deck fire, dual hydraulic system failure, electrical faults which result in only critical systems remaining, or any other situation determined by the crew to present a significantly adverse effect on safety if the flight is continued. In each case, it is the responsibility of the Captain to assess the situation and execute sound judgment to determine the safest course of action.
THAT is why some would continue to destination, depending on the totality of the circumstances.
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From: way down south
We had a similar incident in our airline (GF) about a month ago from BAH to KUL. They lost all the crew O2 about an hour & a half before destination so they landed at the nearest suitable airport. The management & the trainers all agreed with the Capt's decision. After all who wants to keep pushing when you have a suitable place to land? Since it always seems that when 1 thing goes wrong there are bound to be other problems cropping up. As they say "Best to think about it on the ground"
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From: Cork....like.
Having done very many crossings of the pond, I would consider that the interviewee's answer is the best I've read so far. No O2, = not going far!
(of course I'm assuming that it's the cockpit gaseous oxygen that has depleted, as the SLF O2 is chemically generated). Upon noticing that you have little or no cockpit O2 left, it's down to 10,000 or MSA if higher,(it is'nt on the NYC-LHR route unless if over Greenland), and, yes, fuel burn will be much higher, thus it is unlikely that you will make landfall eastbound at this lower altitude. Upon consideration, this was a clever interview question. The answers from candidates would be expected to be commensurate with experience. Don't know your experience level, but in any case, your answer was SAFE.
Hope this helps, and good luck with those interviews
(of course I'm assuming that it's the cockpit gaseous oxygen that has depleted, as the SLF O2 is chemically generated). Upon noticing that you have little or no cockpit O2 left, it's down to 10,000 or MSA if higher,(it is'nt on the NYC-LHR route unless if over Greenland), and, yes, fuel burn will be much higher, thus it is unlikely that you will make landfall eastbound at this lower altitude. Upon consideration, this was a clever interview question. The answers from candidates would be expected to be commensurate with experience. Don't know your experience level, but in any case, your answer was SAFE.
Hope this helps, and good luck with those interviews
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From: Seattle
If you consider a blind descent to 10,000' over the middle of the Atlantic as "safe" under the given conditions, I certainly wouldn't hire you. To risk fuel starvation because of an abnormal condition that has no immediate adverse effects is IMO a bad decision.
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From: Sale, Australia
To risk fuel starvation because of an abnormal condition
My reading of FAR 121.329 and 121.333 prompts me to agree with the interviewees (R2000/1830) answer. Procceed at 10,000. 121.333(b) in particular I think is most relevent.
"Crewmembers. When operating at flight altitudes above 10,000 feet, the certificate holder shall supply enough oxygen to comply with §121.329, but not less than a two-hour supply for each flight crewmember on flight deck duty. The required two hours supply is that quantity of oxygen necessary for a constant rate of descent from the airplane's maximum certificated operating altitude to 10,000 feet in ten minutes and followed by 110 minutes at 10,000 feet. The oxygen required in the event of cabin pressurization failure by §121.337 may be included in determining the supply required for flight crewmembers on flight deck duty."
That is, no oxygen, no above 10,000. (As I read it. Stand to be corrected)
R2000/1830 - Stick to the radials rather than them whining turbines. (Money aside)
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Brian, I think most here understand the regulations concerning a pressurized aircraft, no one will debate that point, 10,000 ft is where we descend to when the cabin depressurizes, yes we must also carry fuel for this worst case scenario, but going to 10,000 ft. immediately after the loss of crew O2 would not be my immediate action unless ample diversionary airports are available, is this an FAR violation, don't think so.
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From: wherever
I would follow the procedure as layed down in the QRH.
For my type that says
Descend to 10'000 or MEA.
Because of this we would have to divert.
As I would have been keeping track of wx and availability of en-route divs throughout the flight there would be no need for desicion making as to where to go.
The type of descent would depend on where I was ref nat tracks.
The procedures for initial descent out of NAT airspace are well documented.
Once under the tracks and pointing in the right direction I would look again at the fuel required and wx and either cruise descend with protable O2 near by or get down early to the MID teens and then cruise descend from there.
For my type that says
Descend to 10'000 or MEA.
Because of this we would have to divert.
As I would have been keeping track of wx and availability of en-route divs throughout the flight there would be no need for desicion making as to where to go.
The type of descent would depend on where I was ref nat tracks.
The procedures for initial descent out of NAT airspace are well documented.
Once under the tracks and pointing in the right direction I would look again at the fuel required and wx and either cruise descend with protable O2 near by or get down early to the MID teens and then cruise descend from there.
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From: Seattle
That is, no oxygen, no above 10,000. (As I read it. Stand to be corrected)
The OP addressed ONLY a failure of the primary crew O2 (or O2 indication). There has been NO depressurization or indication that one should be expected. Our procedure states:
When the fixed oxygen supply becomes depleted during flight, the crew becomes vulnerable to both smoke
and loss of cabin pressurization.
The following steps should be accomplished to provide the greatest margin of safety under the circumstances:
• Place the cockpit portable oxygen bottle in a location readily available to the Captain.
• Retrieve the two Upper Deck Portable Oxygen Bottles and place one in a location readily available to the First Officer and the other in a location readily available to the Flight Engineer.
• Plan to land at the nearest suitable airport.
• Analyze the possibility of descending to a lower altitude, considering available fuel vs. time to destination. Descent should be a secondary consideration to maintaining adequate fuel reserve, particularly on overwater flights or when traversing widespread areas of poor terminal weather.
• Review the Cockpit Fire/Smoke Evacuation and Rapid Descent Checklists.
and loss of cabin pressurization.
The following steps should be accomplished to provide the greatest margin of safety under the circumstances:
• Place the cockpit portable oxygen bottle in a location readily available to the Captain.
• Retrieve the two Upper Deck Portable Oxygen Bottles and place one in a location readily available to the First Officer and the other in a location readily available to the Flight Engineer.
• Plan to land at the nearest suitable airport.
• Analyze the possibility of descending to a lower altitude, considering available fuel vs. time to destination. Descent should be a secondary consideration to maintaining adequate fuel reserve, particularly on overwater flights or when traversing widespread areas of poor terminal weather.
• Review the Cockpit Fire/Smoke Evacuation and Rapid Descent Checklists.
Note also that descent is specifically a "secondary consideration." There is NO reason to create another (i.e., low fuel) emergency while attempting to mitigate a _potential_ problem.
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From: Sale, Australia
the crew becomes vulnerable to both smoke and loss of cabin pressurization
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From: USofA
Well here is a real life story and I'll try to make it short. The B727 was en route from Washington, Dulles to Salt Lake City. There was an FAA Air Carrier Inspector in the jump seat just aft of the Capt. When about 200 miles east on Denver the Capt. looked back at the S/O panel and noticed the O2 was at Zero. Just about that time the FAA asked to be excused to go back and use the lav. As soon as he was out of the cockpit the Capt called this O2 problem to the S/O's attention and everyone checked their O2 regulators. The F/O's regulator had been left on, thus depleting the O2, Quickly the Capt. moved the Observrs seat regulator to the On position. When the FAA returned and after few minutes the Capt. called the O2 problem out to the crew and said "everyone check their regulators", Well the FAA guys was mortified to find his regulator in the on position. Quickly the Capt. posed the question....should we divert into Denver? The FAA responded with a "please, whatever you do, don't do that". So they continued on to Salt Lake City without further incident. Not sure weather they decended or did any other precautionary planning. The poor FAA guy could probably see him self writing officail letters explaining his actions for the next five years! I can tell this story today as the Capt. has since passed away.
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From: USofA
Complicit in what sense? Maybe the thing went to zero 30 seconds before the Capt noticed it. I have no idea how to implicate the SO as it was the FO's regulator that originally started the sequence of events.
Last edited by Spooky 2; 10th December 2007 at 17:47.
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From: wherever
As the whole crew, Cpt, FO, SO(FE) were aware of the real problem and tricked the FAA guy into a very poor call. Then be glad it didn't turn to pooh.
The voice recorder would have recorded the whole thing.
The voice recorder would have recorded the whole thing.
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From: Over the clouds
Airbus 343. Pax O2 is chemical and you don't have indications. Crew O2 low is a caution msg (amber) and OM says under abnormal procedures, that you may or not have O2. 
. I would rather prefer something like "If you can read this, then you are not dead. That is a good start"
Then, no diversion. Anyway, accidents are always spying me, to change my sweet life. So take two O2 portable bottles into cockpit and connect both quick donning masks to them, they use the same fast connector
. In case you don't have the same connector, then you have a problem cause the first aid masks, mix the O2 with fresh air and if instead air you are into smoke atmosphere you are going to be a passive smoker. Another option are the smoke hoods that gives you 15 minutes but no communication with the other pilot or ATC. (very noisy the O2 generator).
. I would rather prefer something like "If you can read this, then you are not dead. That is a good start" Then, no diversion. Anyway, accidents are always spying me, to change my sweet life. So take two O2 portable bottles into cockpit and connect both quick donning masks to them, they use the same fast connector
. In case you don't have the same connector, then you have a problem cause the first aid masks, mix the O2 with fresh air and if instead air you are into smoke atmosphere you are going to be a passive smoker. Another option are the smoke hoods that gives you 15 minutes but no communication with the other pilot or ATC. (very noisy the O2 generator).
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From: USofA
This probably means very little but in the B777 in the QRH Unannunciated Checklist there is no guidence regarding crew action that may be associated with an EICAS message that says Crew Oxygen Low. Ditto for a Pax Oxygen Low message. This assumes that your 777 is equipped with a gaseous system as opposed to the 15 or 20 minute canisters. I guess it's fair to say that they will leave it up to the crew to act in the most prudent, safe manner to get the airpane and pax to their destination or alternate.
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From: West
Flight Detent....SATCOM
Flight Detent wrote,
"None...
I'm thinking after all this talking, you may be interrupted by approach control wanting you to descend at your planned destination....problem solved!
Cheers...FD "
Well, that's the beauty of SATCOM. A three minute conference call is all you would need. Since this is not a "fast" emergency, there's time to think and talk about all of the implications. That's just me, and not the only way to handle this one.
"None...
I'm thinking after all this talking, you may be interrupted by approach control wanting you to descend at your planned destination....problem solved!
Cheers...FD "
Well, that's the beauty of SATCOM. A three minute conference call is all you would need. Since this is not a "fast" emergency, there's time to think and talk about all of the implications. That's just me, and not the only way to handle this one.
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From: Cork....like.
For the attention of Intruder, no-one flying the Atlantic should be flying "blind" in any case - that's why all proficent operators will have not only the closest alternate airport pre-programmed in their FMS, but also the approach in use, for the conditions reported.
Most Atlantic crossings these days are performed by Aircraft operating under ETOPS constraints, one of which is the carriage of fuel for the (hopefully) hypothetically implausable "critical fuel scenario".
Therefore, a descent to 10,000 ft, in the event of a loss of cockpit O2, over the Atlantic, and obvious diversion, to repair , is the only course of action I could consider.
Most Atlantic crossings these days are performed by Aircraft operating under ETOPS constraints, one of which is the carriage of fuel for the (hopefully) hypothetically implausable "critical fuel scenario".
Therefore, a descent to 10,000 ft, in the event of a loss of cockpit O2, over the Atlantic, and obvious diversion, to repair , is the only course of action I could consider.