Three hours at FL100
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Three hours at FL100
This flight got to 24,000 feet, then squawked 7700 and dropped 14,000 feet in 5 minutes, which I assume was due to a loss of cabin pressure. I was expecting it to land at a nearby airfield, but it proceeded to fly to its destination, arriving about an hour late, and having flown for about three hours at just below 10,000 feet. Is this normal?
Fuel flow will be higher but why not if it was pressurisation only? Especially if you've got enough fuel and the maintenance needed might be available at the destination. During the Cold War all (well most of them) Berlin flights went at around 10k feet through the Berlin air corridors through east Germany due to allied agreements from piston engine days.
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Fuel flow will be higher but why not if it was pressurisation only? Especially if you've got enough fuel and the maintenance needed might be available at the destination. During the Cold War all (well most of them) Berlin flights went at around 10k feet through the Berlin air corridors through east Germany due to allied agreements from piston engine days.
If you're going from A to B then you only want to go to C if it's really necessary for flight safety. Planes don't require pressurisation at 10,000ft, but they do use a lot more fuel so one of the main considerations is can we continue our not.
Had that years ago on Banff 727 TUL- ORD - passenger window started to emit loud whistling noise, Captain summoned, drop to 10,000ft and slog in all the way.
So there is no automatic need to divert - it's not going to fall out of the sky or explode. This assumes reasonable weather and flying conditions at FL100, and sufficient fuel of course.
Making that call is what the pilots will decide as part of their TDODAR deliberations, along with passenger and crew comfort.
I was taught it was all to do with the Partial pressure of Oxygen at FL100. After all, the air we breathe is only 20% Oxygen anyway.
Sufficient there for the human body to operate then. Above FL130, a different matter.
Even normal pressurised cabin altitudes are FL80 -100.
So only the fuel state/burn at that level is the final deciding factor on whether to continue.
Sufficient there for the human body to operate then. Above FL130, a different matter.
Even normal pressurised cabin altitudes are FL80 -100.
So only the fuel state/burn at that level is the final deciding factor on whether to continue.
well you don't want a window or door popping out but all in all it seemed to be the logical thing to do - it was damn turbulent tho' at the lower levels in mid summer
Professional Student
This flight got to 24,000 feet, then squawked 7700 and dropped 14,000 feet in 5 minutes, which I assume was due to a loss of cabin pressure. I was expecting it to land at a nearby airfield, but it proceeded to fly to its destination, arriving about an hour late, and having flown for about three hours at just below 10,000 feet. Is this normal?
Professional Student
If the crew had a pressurisation problem, then descended, decided it wasn't a problem at the lower level, and then continued to destination, I'd expect the latter case.
