Narrative:

I was flying the pomg out of ont. At 10000 ft, the captain directed me to level off. He then asked ATC for an intermediate level and ATC approved. He then pointed out the cabin pressure. I looked at the pressure control knob and saw it was in manual. We closed the outflow valve and regained control of the cabin pressure. We asked ATC to resume climb and continued normal operations for an uneventful flight. This flight was an originator and I remember testing the outflow valve during preflight. I don't remember what broke my habit pattern, but I failed to return the mode selector to automatic. This was a new pressure control without the 'flight-ground' switch. My flow for after start is 'peeters, heaters, bleeds, flight.' without the switch, I stopped checking for the 'automatic.' believe me, this lesson was learned. My flow is now 'flight/automatic' with a twist of the knob to ensure it is in automatic. I have also added a 5000 ft check of cabin pressurization. Supplemental information from acn 537942: first officer inadvertently left the switch in manual. I, as the captain, failed to notice this on taxi out. We caught the error during our 10000 ft check. I instructed the first officer to level off. We took the appropriate steps to bring the cabin pressure under control. The first officer is uncertain why he left the mode selector in manual, but believes he was distraction by a radio transmission. We were fortunate in 2 respects. First, that we caught the problem when we did (I always try to physically touch both the pressure and climb gauge at 10000 ft). And second, that we were not in rapid climb out of one of our high altitudes cities.

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Original NASA ASRS Text

Title: TEMPORARY LOSS OF CABIN PRESSURE WHEN A B737-700 FLC CLBS TO 10000 FT BEFORE THE PIC REALIZES THAT THE FO LEFT THE CABIN PRESSURE SWITCH IN MANUAL CTL DEP ONT, CA.

Narrative: I WAS FLYING THE POMG OUT OF ONT. AT 10000 FT, THE CAPT DIRECTED ME TO LEVEL OFF. HE THEN ASKED ATC FOR AN INTERMEDIATE LEVEL AND ATC APPROVED. HE THEN POINTED OUT THE CABIN PRESSURE. I LOOKED AT THE PRESSURE CTL KNOB AND SAW IT WAS IN MANUAL. WE CLOSED THE OUTFLOW VALVE AND REGAINED CTL OF THE CABIN PRESSURE. WE ASKED ATC TO RESUME CLB AND CONTINUED NORMAL OPS FOR AN UNEVENTFUL FLT. THIS FLT WAS AN ORIGINATOR AND I REMEMBER TESTING THE OUTFLOW VALVE DURING PREFLT. I DON'T REMEMBER WHAT BROKE MY HABIT PATTERN, BUT I FAILED TO RETURN THE MODE SELECTOR TO AUTO. THIS WAS A NEW PRESSURE CTL WITHOUT THE 'FLT-GND' SWITCH. MY FLOW FOR AFTER START IS 'PEETERS, HEATERS, BLEEDS, FLT.' WITHOUT THE SWITCH, I STOPPED CHKING FOR THE 'AUTO.' BELIEVE ME, THIS LESSON WAS LEARNED. MY FLOW IS NOW 'FLT/AUTO' WITH A TWIST OF THE KNOB TO ENSURE IT IS IN AUTO. I HAVE ALSO ADDED A 5000 FT CHK OF CABIN PRESSURIZATION. SUPPLEMENTAL INFO FROM ACN 537942: FO INADVERTENTLY LEFT THE SWITCH IN MANUAL. I, AS THE CAPT, FAILED TO NOTICE THIS ON TAXI OUT. WE CAUGHT THE ERROR DURING OUR 10000 FT CHK. I INSTRUCTED THE FO TO LEVEL OFF. WE TOOK THE APPROPRIATE STEPS TO BRING THE CABIN PRESSURE UNDER CTL. THE FO IS UNCERTAIN WHY HE LEFT THE MODE SELECTOR IN MANUAL, BUT BELIEVES HE WAS DISTR BY A RADIO XMISSION. WE WERE FORTUNATE IN 2 RESPECTS. FIRST, THAT WE CAUGHT THE PROB WHEN WE DID (I ALWAYS TRY TO PHYSICALLY TOUCH BOTH THE PRESSURE AND CLB GAUGE AT 10000 FT). AND SECOND, THAT WE WERE NOT IN RAPID CLB OUT OF ONE OF OUR HIGH ALTS CITIES.

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.