why single pack limit flight level
Just what I was going for, John. How about it Airsupport? Can you agree to some analysis and comment on your posts with out the emotive stuff?
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AMC 25.831(a)
Ventilation
The supply of fresh air in the event of the loss of one source, should not be less than 0.18 kg/min (0·4 lb/min) per person for any period exceeding five minutes. However, reductions below this flow rate may be accepted provided that the compartment environment can be maintained at a level which is not
hazardous to the occupant.
from CS 25
Ventilation
The supply of fresh air in the event of the loss of one source, should not be less than 0.18 kg/min (0·4 lb/min) per person for any period exceeding five minutes. However, reductions below this flow rate may be accepted provided that the compartment environment can be maintained at a level which is not
hazardous to the occupant.
from CS 25
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Just what I was going for, John. How about it Airsupport? Can you agree to some analysis and comment on your posts with out the emotive stuff?
No prob AS, so can you discuss a point you brought up? You said you couldn't fly a particular route with a bleed problem because of the high MSA and increased chance of a depressurisation. I simply tried to bring up the idea that there is ALWAYS a risk of depressurisation and that most operators are required to have strategies to deal with them.
Is it the case that in your operation (and if it is it isn't your fault!) you can operate over terrain where you would not be able to guarentee getting the pax down to FL140 before running out of O2 in a depressurisation situation?
Is it the case that in your operation (and if it is it isn't your fault!) you can operate over terrain where you would not be able to guarentee getting the pax down to FL140 before running out of O2 in a depressurisation situation?
Airsupport,
I've given you quite some time to reply, but you seem to have left the building. You seem to take any attempt to Analise the rules you fly under, as you interpret them by your statements, as some type of personal attack. Not the case. You made a statement, and subsequently seemed to try and defend it, that peaked my interest. I was simply asking you to definitively state what I thought you were implying, while pointing out it was different (and IMHO not as safe) as operational rules from other regulators.
To summaries- You said you could not operate a particular route single bleed because of the increased risk of depressurisation, and the inability to guarantee oxygen supply to the pax whilst over terrain that would preclude a descent below 14000'. I pointed out that most operations require that guarantee even when all systems are operating.
I would simply like a confirmation that, under Aussie regulations, it is considered a guarantee that you will not depressurise if you have a fully-functioning bleed/aircon system, and that you therefore do not need to be able to descend below 14000' before the pax O2 runs out if you should.
I've given you quite some time to reply, but you seem to have left the building. You seem to take any attempt to Analise the rules you fly under, as you interpret them by your statements, as some type of personal attack. Not the case. You made a statement, and subsequently seemed to try and defend it, that peaked my interest. I was simply asking you to definitively state what I thought you were implying, while pointing out it was different (and IMHO not as safe) as operational rules from other regulators.
To summaries- You said you could not operate a particular route single bleed because of the increased risk of depressurisation, and the inability to guarantee oxygen supply to the pax whilst over terrain that would preclude a descent below 14000'. I pointed out that most operations require that guarantee even when all systems are operating.
I would simply like a confirmation that, under Aussie regulations, it is considered a guarantee that you will not depressurise if you have a fully-functioning bleed/aircon system, and that you therefore do not need to be able to descend below 14000' before the pax O2 runs out if you should.
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Thread drift?
On other CASA registered aircraft that fly over Afghanistan etc there are very strict rules and limits regarding the amount of pax O2 available before departing Asia (BKK, SIN, HKG).
On the 744 the PAX oxygen must be full as the 744 has bottled pax oxy but the 767 has chemical oxygen generators good for 35mins.
Question? Are there chemical oxygen generator available for the 767 with greater capacity than 35mins, if so how long would they need to last to get you out of worst case scenario in Afghan airspace mentioned in this thread?
Greater than 14,000 etc
NB I know of other Chemical oxy generators fitted to other aircraft good for up to 45mins but each assy are larger in installation. e.g as fitted to some A330-200
On other CASA registered aircraft that fly over Afghanistan etc there are very strict rules and limits regarding the amount of pax O2 available before departing Asia (BKK, SIN, HKG).
On the 744 the PAX oxygen must be full as the 744 has bottled pax oxy but the 767 has chemical oxygen generators good for 35mins.
Question? Are there chemical oxygen generator available for the 767 with greater capacity than 35mins, if so how long would they need to last to get you out of worst case scenario in Afghan airspace mentioned in this thread?
Greater than 14,000 etc
NB I know of other Chemical oxy generators fitted to other aircraft good for up to 45mins but each assy are larger in installation. e.g as fitted to some A330-200
So, Australia DOES have rules regarding LSALT and oxygen availability, as per most other regulators.
So why would having one bleed source change route capability WRT Pax Oxy requirements?
So why would having one bleed source change route capability WRT Pax Oxy requirements?
As I was saying:-
Good job by the crew but it makes my point-
Airsupport, I think you were in error saying that a bleed problem meant you couldn't fly a particular route because of depess- Pax O2 issues. Aircraft have to be able to cope with a loss of pressurisation no matter how many bleed systems they have operating.
QANTAS flight plunged 20,000 feet after a door "popped" mid-flight, passengers are reporting.
The plane has just made an emergency landing in the Philippines following reports that a door "popped", causing depressurisation, during a flight between London and Melbourne.
Qantas is refusing to confirm the incident, but passengers who have called Herald Sun Online say oxygen masks dropped from the ceiling during the incident.
Others said the plane suddenly plunged from 30,000 feet to 10,000 feet.
Luci of Melbourne told NEWS.com.au that her father, who was on the flight, said "there was a large hole in the fuselage where the landing covers are located".
"(My father said) everybody is fine and they have disembarked in Manilla where they're awaiting another plane," Luci said.
"He also said that the staff were very calm and that the emergency procedures went very smoothly."
One passenger reported the pilot did 'an amazing job' of controlling the craft.
Flight QF 30 was due to arrive in Melbourne around 10pm tonight.
It was one hour from Hong Kong when the incident occured.
The plane is now on the tarmac at Manila airport with all passengers - the majority of them Australians - on board.
The plane has just made an emergency landing in the Philippines following reports that a door "popped", causing depressurisation, during a flight between London and Melbourne.
Qantas is refusing to confirm the incident, but passengers who have called Herald Sun Online say oxygen masks dropped from the ceiling during the incident.
Others said the plane suddenly plunged from 30,000 feet to 10,000 feet.
Luci of Melbourne told NEWS.com.au that her father, who was on the flight, said "there was a large hole in the fuselage where the landing covers are located".
"(My father said) everybody is fine and they have disembarked in Manilla where they're awaiting another plane," Luci said.
"He also said that the staff were very calm and that the emergency procedures went very smoothly."
One passenger reported the pilot did 'an amazing job' of controlling the craft.
Flight QF 30 was due to arrive in Melbourne around 10pm tonight.
It was one hour from Hong Kong when the incident occured.
The plane is now on the tarmac at Manila airport with all passengers - the majority of them Australians - on board.
Airsupport, I think you were in error saying that a bleed problem meant you couldn't fly a particular route because of depess- Pax O2 issues. Aircraft have to be able to cope with a loss of pressurisation no matter how many bleed systems they have operating.
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320-232 Mel - you can DISPATCH with one pack inop and have NO LIMITATION on the Flight Level (only if the speedbrakes work), if no speedbrake - limit FL 315 in one pack.
In flight, pack failure - no limitation.
In flight, pack failure - no limitation.
Last edited by dkz; 25th Jul 2008 at 14:55.
what the heck are the new guys taught in ground school?
Decades back, the lectures on a Viscount course I attended as a pilot went for six bloody weeks and that included two full 8 hour days on the autopilot alone which had about six knobs to twiddle. While CBT is sufficient to pass a type rating it is up to the student to research further if he desires. The internet is marvellous for those keen enough to research stuff.
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Not all twins can maintain cabin pressure at cruise altitude with one pack. The MD80 definitely can't. If you lose a pack in an MD80, you are required to descend to FL250 in order to maintain the cabin. This happened to me once while at FL330, and the cabin altitude began climbing around 300-400 fpm immediately. We descended to FL250, but that was not even enough. The cabin still was climbing. We then descended to FL230, and found that we could hold the cabin fine at that altitude.
