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Foxcotte
11th Dec 2012, 07:46
I had posted this on the Africa section, but as suggested I'm reposting here in the hope that there is someone out there who can settle my curiosity...

I flew from Nairobi to Jo'burg a week ago on an SAA 737-800. The aircraft was only 1/3 full, and everything was absolutely normal until we were top of climb. Then I got a few 'ear pops' which was the first clue something odd was up. Then there was a substantial power reduction, power back up, power reduction and the aircraft was fairly steeply descended. I'm not a big jet pilot but from experience flying a corporate jet it all seemed rather odd. Eventually we leveled out somewhat lower than original, but there was a serious out of sync vibration in the cabin. This vibration continued on and off for the next hour at least, with various power changes as the crew tried to sort something out. This was in sustained level cruise and the engines were stabilised for 15 minutes at a time, then went out of sync again etc. After sometime the flight deck explained that they had had a problem with pressurisation at 38,000' so had come back down to 28,000' and were continuing onto Jo'burg as scheduled. The rest of the flight was normal, except we seemed to have several large changes of heading which I don't recall from past flights on the same route.

Lastly, there was a few minutes when the cockpit door was ajar and we could see a bank of annunciators in the centre panel that seemed to have at least 3 amber and 1 red lights showing on the top row?. Again I know nothing about the 737 but small jets normally operate with a black/clear annunciator panel.

As a postscript to the above, by coincidence a friend was travelling the reverse route the very next day on SAA, and shortly out of Jo'burg the crew on the 737-800 announced they had a pressurisation problem and turned back to Jo'burg at FL080' all the way back in. He waited a while and got put on another aircraft to Nairobi a few hours later.

So, can anyone out there shed any light on what was happening, what went wrong or why?? I'm just curious more than anything else. I'm also guessing that there are very different SOP's for pressurisation issues when heading inbound to home-base than when outbound. But I can't help wonder if it was the same aircraft and the problem hadn't been rectified satisfactorily after the inbound flight..

Fullblast
11th Dec 2012, 08:42
Not easy to figure out what happened, it could have been a pack problem, bleed or maybe just a broken seal.

Also the 737 operates with clear annunciator panel, if you have a trouble you acknowledge the panel annunciation then cancel like all other planes I guess.

I don't think you'll satisfy your curiosity unless one of the pilots shows up here.

FB

Tapshi
11th Dec 2012, 08:56
A red annunciation for a pressurization problem on the 737. That is new.
The parking brake light it might be :p

Fullblast
11th Dec 2012, 10:08
Parking brake light in flight? :eek:

FB

BOAC
11th Dec 2012, 11:28
Did you notice the :p?

Fullblast
11th Dec 2012, 22:14
Yes I did, and?

Tapshi
12th Dec 2012, 06:04
:ugh: Gosh. I was kidding fullblast!

Fullblast
12th Dec 2012, 12:48
Did you notice the :eek:? That might be related eventually to the crew not to your comment. Anyway, your comment was too sarcastic in my opinion, Foxcotte clearly said he knows nothing about 737, but I can tell you that other planes have red indication for pressurization problem as well, so his guess wasn't stupid as you may think.

FB