Pressurization issues?
Jul 18, 2023 | 3:48 pm
#1
Original Poster
Join Date: Mar 2016
Posts: 645
Pressurization issues?
Delta 1637 today TUS-ATL. 45 minutes into the flight the pilot orders service discontinuation and for the flight attendants to be seated. OK, seems normal. 45 minutes later I asked one of the FAs what was up. He said there were "pressurization issues." We dropped from FL 34,000 down to 25,000 and continuing the flight as normal.
Anybody ever seen this before? BTW, not complaining, better than a divert.
Anybody ever seen this before? BTW, not complaining, better than a divert.
Jul 18, 2023 | 5:38 pm
#2
Join Date: Feb 2008
Location: Auckland, NZ/New York, NY/ATL
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Whats strange about that explanation is that, if it was a pressurization issue, usually they would have to descend to below 10K feet for equalization.
Jul 18, 2023 | 6:23 pm
#3
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< speculation >
failure of an A/C pack, and the remaining ones couldn't maintain enough output pressure at 34000
failure of an A/C pack, and the remaining ones couldn't maintain enough output pressure at 34000
Jul 18, 2023 | 11:16 pm
#4
Join Date: Feb 2015
Location: ANC
Programs: DL DM
Posts: 2,720
Looks like it was a B739. I fly 737s and a -900 is limited to 25,000 on a single pack, so it does look like it was some sort of pack failure/overtemp/overpressure that wouldnt reset, so thats the likely reason for the descent.
You are lucky that on a flight of that length it didnt divert due to the increased fuel consumption for the lower altitude. Dispatch mustve been able to run the numbers and confirm enough fuel onboard. Always good to have extra gas!
You are lucky that on a flight of that length it didnt divert due to the increased fuel consumption for the lower altitude. Dispatch mustve been able to run the numbers and confirm enough fuel onboard. Always good to have extra gas!
Jul 19, 2023 | 2:33 pm
#5
Join Date: Nov 1999
Location: Tucson, AZ USA
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Posts: 1,594
One pack out would be 25K ... I assume to lower the workload on the other pack and be closer to 10K if it were to also fail.