Narrative:

Divert for fuel. On takeoff the captain's sliding window had an air leak that seemed to increase in noise level in the climb out. The first officer noted passing approximately 7000 ft MSL that we were not pressurizing. All indications were that the window was closed and locked but I pushed upon it rather forcefully for a moment as we began to level at 8000 ft MSL. The cabin altitude slowed down at the same time so I thought the pressurization problem was connected to the air leak at the window. We coordinated with clt and dispatch and began a divert to rdu for maintenance. Once started to rdu we pulled out the QRH and went through the loss of pressurization checklist. As we did so it was apparent the pressurization checklist. As we did so it was apparent the pressurization lever was in the manual position and the outflow valve was in the full open position. We brought the lever to the automatic position and the cabin began to pressurize normally. With all the time spent at 8000 ft we had used enough fuel that we could not continue to dfw as planned so dispatch and I agreed that a fuel stop at rdu was necessary. We landed at rdu and refueled and proceeded to dfw without further incident. The first officer noted on the walkaround that the outflow valve was in the full open position, normal for the automatic position of the lever. On the before starting engines checklist I noted the outflow valve indicator in the cockpit was in the full open position and believed I saw the lever in the up or automatic position and reported it accordingly. It is more likely that since the valve indication was full open (normal for automatic) and not partially open (normal for manual on parking for overnights) I expected to see the lever in the up and automatic position and that is what I registered and read back as the response to the checklist challenge. I normally physically place my hands on an item as I read off its actual position to prevent an occurrence such as this. In this instance, I did not slide my hand under the lever to verify it was up. I touched it and gave the response as my eyes went on to the next item on the checklist. Supplemental information from acn 601862: the QRH was gotten out and the pressurization flow light (unscheduled cabin climb checklist was initiated). While accomplishing the checklist, the cabin altitude control lever was discovered to be in the manual (down) position. The lever was selected to the automatic (up) position and the aircraft began to pressurize normally. I now believe that the outflow valve had not been properly set as called for in the overnight termination portion of the parking checks the night before.

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Original NASA ASRS Text

Title: MD80 CREW DEPARTED WITH THE PRESSURIZATION OUTFLOW VALVE IN THE MANUAL 'OPEN' POS. THE CREW WAS REQUIRED TO MAKE A FUEL STOP BECAUSE THE ACFT CABIN WAS NOT PRESSURIZING.

Narrative: DIVERT FOR FUEL. ON TKOF THE CAPT'S SLIDING WINDOW HAD AN AIR LEAK THAT SEEMED TO INCREASE IN NOISE LEVEL IN THE CLBOUT. THE FO NOTED PASSING APPROX 7000 FT MSL THAT WE WERE NOT PRESSURIZING. ALL INDICATIONS WERE THAT THE WINDOW WAS CLOSED AND LOCKED BUT I PUSHED UPON IT RATHER FORCEFULLY FOR A MOMENT AS WE BEGAN TO LEVEL AT 8000 FT MSL. THE CABIN ALT SLOWED DOWN AT THE SAME TIME SO I THOUGHT THE PRESSURIZATION PROB WAS CONNECTED TO THE AIR LEAK AT THE WINDOW. WE COORDINATED WITH CLT AND DISPATCH AND BEGAN A DIVERT TO RDU FOR MAINT. ONCE STARTED TO RDU WE PULLED OUT THE QRH AND WENT THROUGH THE LOSS OF PRESSURIZATION CHKLIST. AS WE DID SO IT WAS APPARENT THE PRESSURIZATION CHKLIST. AS WE DID SO IT WAS APPARENT THE PRESSURIZATION LEVER WAS IN THE MANUAL POS AND THE OUTFLOW VALVE WAS IN THE FULL OPEN POS. WE BROUGHT THE LEVER TO THE AUTO POS AND THE CABIN BEGAN TO PRESSURIZE NORMALLY. WITH ALL THE TIME SPENT AT 8000 FT WE HAD USED ENOUGH FUEL THAT WE COULD NOT CONTINUE TO DFW AS PLANNED SO DISPATCH AND I AGREED THAT A FUEL STOP AT RDU WAS NECESSARY. WE LANDED AT RDU AND REFUELED AND PROCEEDED TO DFW WITHOUT FURTHER INCIDENT. THE FO NOTED ON THE WALKAROUND THAT THE OUTFLOW VALVE WAS IN THE FULL OPEN POS, NORMAL FOR THE AUTO POS OF THE LEVER. ON THE BEFORE STARTING ENGS CHKLIST I NOTED THE OUTFLOW VALVE INDICATOR IN THE COCKPIT WAS IN THE FULL OPEN POS AND BELIEVED I SAW THE LEVER IN THE UP OR AUTO POS AND RPTED IT ACCORDINGLY. IT IS MORE LIKELY THAT SINCE THE VALVE INDICATION WAS FULL OPEN (NORMAL FOR AUTO) AND NOT PARTIALLY OPEN (NORMAL FOR MANUAL ON PARKING FOR OVERNIGHTS) I EXPECTED TO SEE THE LEVER IN THE UP AND AUTO POS AND THAT IS WHAT I REGISTERED AND READ BACK AS THE RESPONSE TO THE CHKLIST CHALLENGE. I NORMALLY PHYSICALLY PLACE MY HANDS ON AN ITEM AS I READ OFF ITS ACTUAL POS TO PREVENT AN OCCURRENCE SUCH AS THIS. IN THIS INSTANCE, I DID NOT SLIDE MY HAND UNDER THE LEVER TO VERIFY IT WAS UP. I TOUCHED IT AND GAVE THE RESPONSE AS MY EYES WENT ON TO THE NEXT ITEM ON THE CHKLIST. SUPPLEMENTAL INFO FROM ACN 601862: THE QRH WAS GOTTEN OUT AND THE PRESSURIZATION FLOW LIGHT (UNSCHEDULED CABIN CLB CHKLIST WAS INITIATED). WHILE ACCOMPLISHING THE CHKLIST, THE CABIN ALT CTL LEVER WAS DISCOVERED TO BE IN THE MANUAL (DOWN) POS. THE LEVER WAS SELECTED TO THE AUTO (UP) POS AND THE ACFT BEGAN TO PRESSURIZE NORMALLY. I NOW BELIEVE THAT THE OUTFLOW VALVE HAD NOT BEEN PROPERLY SET AS CALLED FOR IN THE OVERNIGHT TERMINATION PORTION OF THE PARKING CHKS THE NIGHT BEFORE.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.