Narrative:

Cabin pressurization failure. After takeoff from bdl at about 16000 ft a cabin altitude horn went off in the cockpit. The PF was the first officer, so I immediately scanned the instrument panel for some indication of what had caused the horn, no lights were illuminated to indicate the cause for the horn. Our climb rate was higher than normal due to our light load and at about FL190 the master caution light came indicating a problem on the 'overhead' panel. I looked up and saw that the 'passenger oxygen on' light was illuminated. I then checked the cabin pressure and saw that it was above 14000 ft. I put my oxygen mask on, took control of the aircraft, and told the first officer to put his oxygen on also. I further told him to get the book out and try to fix the problem. He went to manual control which seemed to be working. I made a PA to the passenger to calm them and told them that we were experiencing a malfunction in the pressurization system and to remain on oxygen until told otherwise. I leveled the aircraft at FL190 and informed ATC that we had a problem with our pressurization system and needed a lower altitude while we worked the problem. We were given clearance to 11000 ft and I started down. The manual system was working, so I told the first officer to switch to 'alternate' which also seemed to work. We continued on to ord at FL280 (due to reserves) and landed on time. If a 'cabin pressure' light was incorporated into the master caution system, we could have solved the problem earlier and prevented the deployment of the passenger oxygen masks. Of concern was the fact that 11 oxygen panels failed to deploy. All discrepancies were written up in the logbook for maintenance action.

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Original NASA ASRS Text

Title: B737 CREW HAD THE OXYGEN MASKS IN THE CABIN DEPLOY ON CLBOUT IN ZBW CLASS E.

Narrative: CABIN PRESSURIZATION FAILURE. AFTER TKOF FROM BDL AT ABOUT 16000 FT A CABIN ALT HORN WENT OFF IN THE COCKPIT. THE PF WAS THE FO, SO I IMMEDIATELY SCANNED THE INST PANEL FOR SOME INDICATION OF WHAT HAD CAUSED THE HORN, NO LIGHTS WERE ILLUMINATED TO INDICATE THE CAUSE FOR THE HORN. OUR CLB RATE WAS HIGHER THAN NORMAL DUE TO OUR LIGHT LOAD AND AT ABOUT FL190 THE MASTER CAUTION LIGHT CAME INDICATING A PROB ON THE 'OVERHEAD' PANEL. I LOOKED UP AND SAW THAT THE 'PAX OXYGEN ON' LIGHT WAS ILLUMINATED. I THEN CHKED THE CABIN PRESSURE AND SAW THAT IT WAS ABOVE 14000 FT. I PUT MY OXYGEN MASK ON, TOOK CTL OF THE ACFT, AND TOLD THE FO TO PUT HIS OXYGEN ON ALSO. I FURTHER TOLD HIM TO GET THE BOOK OUT AND TRY TO FIX THE PROB. HE WENT TO MANUAL CTL WHICH SEEMED TO BE WORKING. I MADE A PA TO THE PAX TO CALM THEM AND TOLD THEM THAT WE WERE EXPERIENCING A MALFUNCTION IN THE PRESSURIZATION SYS AND TO REMAIN ON OXYGEN UNTIL TOLD OTHERWISE. I LEVELED THE ACFT AT FL190 AND INFORMED ATC THAT WE HAD A PROB WITH OUR PRESSURIZATION SYS AND NEEDED A LOWER ALT WHILE WE WORKED THE PROB. WE WERE GIVEN CLRNC TO 11000 FT AND I STARTED DOWN. THE MANUAL SYS WAS WORKING, SO I TOLD THE FO TO SWITCH TO 'ALTERNATE' WHICH ALSO SEEMED TO WORK. WE CONTINUED ON TO ORD AT FL280 (DUE TO RESERVES) AND LANDED ON TIME. IF A 'CABIN PRESSURE' LIGHT WAS INCORPORATED INTO THE MASTER CAUTION SYS, WE COULD HAVE SOLVED THE PROB EARLIER AND PREVENTED THE DEPLOYMENT OF THE PAX OXYGEN MASKS. OF CONCERN WAS THE FACT THAT 11 OXYGEN PANELS FAILED TO DEPLOY. ALL DISCREPANCIES WERE WRITTEN UP IN THE LOGBOOK FOR MAINT ACTION.

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.