Really happened...
I was flying a 737-200 back in the day.
The pressurisation mode, due to system faults, was manual.
Taking off from MEM towards the east, the storms were so bad, I told the FO I will take the radios. Didn't want to waste time explaining to him what I wanted and the palava of waiting for him to understand and also to have a rapid response if ATC had issues about my desired headings etc. Fought tooth and nail for a good 20 minutes or so avoiding storms and climbing. finally came out the other side into the clear and could take a breath, looked over and FO was dead to the world, asleep. I did a quick scan of the panels and came to the pressurization panel and was confused with seeing the differential needle sitting between the S and the 0. Thought a second, then hit the FO, closed the thrust levers, and told ATC we were descending now due to severe turbulence. I wanted to immediately reduce the input of any further air pressure, hence closing the thrust levers. The FO finally got to work on the outflow valve and we both watched the needle descend through the DIFF PRESS on down to the normal range. To this day I am amazed we didn't blow any windows or seals out. When I landed back at MEM, I wrote in the tech log, "check pressure relief valve"
The engineer asked why I wrote that up and I just looked at him with a big smile and said, "it doesn't work!" Yes, part my fault for not keeping the FO awake. Funny that on the same frequency, just after my telling ATC that I was descending now due turbulence, a lie for sure, someone else said the same thing, so there was turbulence somewhere in the area.
So, a bit into the yellow arc is fine.
Last edited by stator vane; 1st May 2017 at 07:40.
Reason: Addition