QF depressurisation event
Join Date: Jun 2007
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As far as the 737 is concerned, it's good up to certified ceiling, according to Boeing. (FL 410) Subject to some caveats, of course. Not that I would necessarily advocate same......
I know in the 320, if the second pack fails, you don’t get a rapid depressurisation. So depending on your height when it fails, you may not actually get the rubber jungle at all.
The FL250 restriction is interesting though. The 320 doesn’t start placing restrictions unless the speed brakes are inop.
The FL250 restriction is interesting though. The 320 doesn’t start placing restrictions unless the speed brakes are inop.
I am reliably informed that there was a time in the recent past when a certain airline in Oz had four A380s each with one pack inop, leaving one working. This went on for several weeks coz it is a major job to replace a pack even if you have the spares, which they didn't.
Trust the statistics, you'll get away with it!
Trust the statistics, you'll get away with it!
I am reliably informed that there was a time in the recent past when a certain airline in Oz had four A380s each with one pack inop, leaving one working. This went on for several weeks coz it is a major job to replace a pack even if you have the spares, which they didn't.
Trust the statistics, you'll get away with it!
Trust the statistics, you'll get away with it!
More that they need the groundtime to be scheduled to replace the heat exchangers. It is not a simple job like on other aircraft. It can take up to 4 shifts to remove rebuild and reinstall an A380 pack.
Bootstrap 1,
That's what I also heard. If the parts become available the ground time needs to be also there and then we need at least 2 crews for, as I am told, about 24 hours to do each aircraft.
Still, it was eventually done and they got away with it. Think of the hours saved on the a/c packs coz they weren't fitted - a big saving of component hours. My friends used to tear their hair out, now they just shrug.
That's what I also heard. If the parts become available the ground time needs to be also there and then we need at least 2 crews for, as I am told, about 24 hours to do each aircraft.
Still, it was eventually done and they got away with it. Think of the hours saved on the a/c packs coz they weren't fitted - a big saving of component hours. My friends used to tear their hair out, now they just shrug.
Join Date: Feb 2019
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What I don't understand is, how come CASA haven't already bypassed legislation and issued a directive to say that no RPT operation is to commence unless that acft has three packs installed (the third one being for an extra level of redundancy), and that no flight is to operate if any one of those three packs are unserviceable ('cos there is always the possibility of a double pack failure). After all, safety is number one.
Well, not that, but perhaps it might be time to revisit the wisdom of applying the pack MEL for certain failures that led to the pack being inop. This is the second (and yesterday, third) time in a year a Qantas aircraft has done the dirty dive subsequent to dispatching with a pack MEL.
I am reliably informed that there was a time in the recent past when a certain airline in Oz had four A380s each with one pack inop, leaving one working. This went on for several weeks coz it is a major job to replace a pack even if you have the spares, which they didn't.
Trust the statistics, you'll get away with it!
Trust the statistics, you'll get away with it!
The question I'm left with though, is why did they end up with a rubber jungle. The aircraft cabin altitude shouldn't climb all that rapidly in the case of a second pack failure, so why didn't they beat it down?
What I don't understand is, how come CASA haven't already bypassed legislation and issued a directive to say that no RPT operation is to commence unless that acft has three packs installed (the third one being for an extra level of redundancy), and that no flight is to operate if any one of those three packs are unserviceable ('cos there is always the possibility of a double pack failure). After all, safety is number one.
So simply ban all MEL operation for Australian based operators. Simples.
Of course, within 12 months there would no longer be any Oz based operators, but what the heck...
Well, not that, but perhaps it might be time to revisit the wisdom of applying the pack MEL for certain failures that led to the pack being inop. This is the second (and yesterday, third) time in a year a Qantas aircraft has done the dirty dive subsequent to dispatching with a pack MEL.
Join Date: Aug 2018
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i think that the point that everyone is making is that with most MELs there is still a level of redundancy. Operating 1 pack inop with only 1 pack remaining gives zero redundancy. You lose that one pack, you’re going to have a depressurisation event.
Or you can live in the real world.
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Who is arguing to get rid of MELs? There are plenty of aircraft defects that are simple no go items. Perhaps operating with only 1 pack operable should be a no go defect. I have flown with plenty of captains at my airline who have refused an aircraft before due to an MEL being applied which may be legal to operate with but which in their opinion has too large an impact on the safety of the operation.