Narrative:

My biggest concern was that there was no communication (or delayed) from the cockpit. I was standing in the doorway of the cockpit, waiting for connecting gate information, and observed the cockpit crew in their oxygen masks. Since my back was to the aisle, I didn't notice the oxygen masks all down. It wasn't until a passenger pressed his call button, and I responded, that I saw them. We (the crew) were confused as to whether this was an inadvertent mask drop or a true decompression. Since we were in our descent, and the captain had just made the PA, I hesitated putting the mask on. We actually waited for the cockpit to make a PA to put them on as a precaution. Everyone -- the passenger and crew -- remained calm, but confused. Callback conversation with reporter revealed the following information: when the reporter went to the cockpit for the connecting gate information and saw the pilots with oxygen masks on, she thought that the masks were part of their sterile cockpit procedures. Her reasoning was that the captain had just announced that they were going to start their descent into dfw. The copilot held up his finger to signal 'wait a min,' and then gave her the list of connecting gates. Never once did he indicate that they were in emergency descent and to don oxygen masks. The flight attendants never got to debrief with the pilots, because not only did a hoard of mechanics meet the flight and rush into the cockpit, but her crew had to rush to their own connecting flight to las. The next month, their airline's office had a conference call with all the flight attendants, but it did not include the pilots. She learned that the #4 flight attendant had gone up to the cockpit to ask what was wrong (after she'd been up there), and that was when the captain finally told everyone to put on their oxygen masks. She said she now knows what the normal sterile cockpit procedures are. She's glad that she could learn from that experience. Supplemental information from acn 455511: FL350 we received a voice warning 'cabin altitude.' checking cabin pressure indicated 9500 ft climbing. Crew donned emergency oxygen masks and initiated immediate descent to 10000 ft. No emergency declared. Passing FL240 cabin altitude went to 14000 ft MSL indicated, and passenger masks deployed in cabin. Cockpit immediately donned our masks prior to descending out of FL350 as a precaution in the event of loss of cabin pressure. During descent, went to initiate the procedure. Upon selecting standby controller, cabin pressure began to slowly descend from 14500 ft as we were passing through FL200 when we noted the pressure decrease. At 10000 ft MSL cabin pressure read 9400 ft MSL and continued to reduce to field elevation at dfw. We did not receive any master caution warning during the event nor did the red warning cabin altitude illuminate. Pack flow was noted at normal pressure indications. Callback conversation with reporter revealed the following information: the captain said it was not a rapid decompression, but a controled descent that he initiated. He later found out that the primary controller and the backup controller failed. The warning devices that normally should have gone off, failed. He believes that, in retrospect, he probably should have declared an emergency to ATC. He didn't know that the purser thought the oxygen masks that he and the copilot had on were part of the sterile cockpit procedure. He was too busy to inform the cabin crew and the passenger what was happening till they got down to 10000 ft and leveled off. He did not know of the interchange of connecting gate information with the purser and the first officer, he was unaware that he had just had a communication problem with the cabin crew until 3 weeks later, when his company called him for a report. He felt that the whole crew should have had a debriefing, but his crew had to run off to a connecting flight. Also, he feels that if this ever happened again, he would react the same way. The plane was immediately taken OTS and both controllers were replaced. Supplemental information from acn 455510: just prior to descent, captain ordered to don oxygen masks and requested I get an immediate descent to 10000 ft MSL. After we initiated descent, I ran the emergency procedure for cabin loss of pressurization. As we were passing FL240, cabin altitude climbed to 14500 ft and started to drop to below 9500 ft at FL200. As we leveled at 10000 ft MSL, cabin pressure read 9400 ft MSL. We did not receive any other warning that the cabin was climbing except for the cockpit voice. We did not receive a red master warning nor did the cabin altitude red warning light illuminate. Other indications were received by us in the cockpit. An uneventful landing was made by the captain at dfw. No emergency was declared as ATC provided us priority handling as a routine request.

Google
 

Original NASA ASRS Text

Title: MULTIPLE PLT CABIN ATTENDANT RPT, S80, LGA-DFW, CABIN PRESSURIZATION PROBS, DSNDING, NON EMER DECOMPRESSION. PRIORITY LNDG. CABIN COM PROB.

Narrative: MY BIGGEST CONCERN WAS THAT THERE WAS NO COM (OR DELAYED) FROM THE COCKPIT. I WAS STANDING IN THE DOORWAY OF THE COCKPIT, WAITING FOR CONNECTING GATE INFO, AND OBSERVED THE COCKPIT CREW IN THEIR OXYGEN MASKS. SINCE MY BACK WAS TO THE AISLE, I DIDN'T NOTICE THE OXYGEN MASKS ALL DOWN. IT WASN'T UNTIL A PAX PRESSED HIS CALL BUTTON, AND I RESPONDED, THAT I SAW THEM. WE (THE CREW) WERE CONFUSED AS TO WHETHER THIS WAS AN INADVERTENT MASK DROP OR A TRUE DECOMPRESSION. SINCE WE WERE IN OUR DSCNT, AND THE CAPT HAD JUST MADE THE PA, I HESITATED PUTTING THE MASK ON. WE ACTUALLY WAITED FOR THE COCKPIT TO MAKE A PA TO PUT THEM ON AS A PRECAUTION. EVERYONE -- THE PAX AND CREW -- REMAINED CALM, BUT CONFUSED. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: WHEN THE RPTR WENT TO THE COCKPIT FOR THE CONNECTING GATE INFO AND SAW THE PLTS WITH OXYGEN MASKS ON, SHE THOUGHT THAT THE MASKS WERE PART OF THEIR STERILE COCKPIT PROCS. HER REASONING WAS THAT THE CAPT HAD JUST ANNOUNCED THAT THEY WERE GOING TO START THEIR DSCNT INTO DFW. THE COPLT HELD UP HIS FINGER TO SIGNAL 'WAIT A MIN,' AND THEN GAVE HER THE LIST OF CONNECTING GATES. NEVER ONCE DID HE INDICATE THAT THEY WERE IN EMER DSCNT AND TO DON OXYGEN MASKS. THE FLT ATTENDANTS NEVER GOT TO DEBRIEF WITH THE PLTS, BECAUSE NOT ONLY DID A HOARD OF MECHS MEET THE FLT AND RUSH INTO THE COCKPIT, BUT HER CREW HAD TO RUSH TO THEIR OWN CONNECTING FLT TO LAS. THE NEXT MONTH, THEIR AIRLINE'S OFFICE HAD A CONFERENCE CALL WITH ALL THE FLT ATTENDANTS, BUT IT DID NOT INCLUDE THE PLTS. SHE LEARNED THAT THE #4 FLT ATTENDANT HAD GONE UP TO THE COCKPIT TO ASK WHAT WAS WRONG (AFTER SHE'D BEEN UP THERE), AND THAT WAS WHEN THE CAPT FINALLY TOLD EVERYONE TO PUT ON THEIR OXYGEN MASKS. SHE SAID SHE NOW KNOWS WHAT THE NORMAL STERILE COCKPIT PROCS ARE. SHE'S GLAD THAT SHE COULD LEARN FROM THAT EXPERIENCE. SUPPLEMENTAL INFO FROM ACN 455511: FL350 WE RECEIVED A VOICE WARNING 'CABIN ALT.' CHKING CABIN PRESSURE INDICATED 9500 FT CLBING. CREW DONNED EMER OXYGEN MASKS AND INITIATED IMMEDIATE DSCNT TO 10000 FT. NO EMER DECLARED. PASSING FL240 CABIN ALT WENT TO 14000 FT MSL INDICATED, AND PAX MASKS DEPLOYED IN CABIN. COCKPIT IMMEDIATELY DONNED OUR MASKS PRIOR TO DSNDING OUT OF FL350 AS A PRECAUTION IN THE EVENT OF LOSS OF CABIN PRESSURE. DURING DSCNT, WENT TO INITIATE THE PROC. UPON SELECTING STANDBY CONTROLLER, CABIN PRESSURE BEGAN TO SLOWLY DSND FROM 14500 FT AS WE WERE PASSING THROUGH FL200 WHEN WE NOTED THE PRESSURE DECREASE. AT 10000 FT MSL CABIN PRESSURE READ 9400 FT MSL AND CONTINUED TO REDUCE TO FIELD ELEVATION AT DFW. WE DID NOT RECEIVE ANY MASTER CAUTION WARNING DURING THE EVENT NOR DID THE RED WARNING CABIN ALT ILLUMINATE. PACK FLOW WAS NOTED AT NORMAL PRESSURE INDICATIONS. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE CAPT SAID IT WAS NOT A RAPID DECOMPRESSION, BUT A CTLED DSCNT THAT HE INITIATED. HE LATER FOUND OUT THAT THE PRIMARY CONTROLLER AND THE BACKUP CONTROLLER FAILED. THE WARNING DEVICES THAT NORMALLY SHOULD HAVE GONE OFF, FAILED. HE BELIEVES THAT, IN RETROSPECT, HE PROBABLY SHOULD HAVE DECLARED AN EMER TO ATC. HE DIDN'T KNOW THAT THE PURSER THOUGHT THE OXYGEN MASKS THAT HE AND THE COPLT HAD ON WERE PART OF THE STERILE COCKPIT PROC. HE WAS TOO BUSY TO INFORM THE CABIN CREW AND THE PAX WHAT WAS HAPPENING TILL THEY GOT DOWN TO 10000 FT AND LEVELED OFF. HE DID NOT KNOW OF THE INTERCHANGE OF CONNECTING GATE INFO WITH THE PURSER AND THE FO, HE WAS UNAWARE THAT HE HAD JUST HAD A COM PROB WITH THE CABIN CREW UNTIL 3 WKS LATER, WHEN HIS COMPANY CALLED HIM FOR A RPT. HE FELT THAT THE WHOLE CREW SHOULD HAVE HAD A DEBRIEFING, BUT HIS CREW HAD TO RUN OFF TO A CONNECTING FLT. ALSO, HE FEELS THAT IF THIS EVER HAPPENED AGAIN, HE WOULD REACT THE SAME WAY. THE PLANE WAS IMMEDIATELY TAKEN OTS AND BOTH CTLRS WERE REPLACED. SUPPLEMENTAL INFO FROM ACN 455510: JUST PRIOR TO DSCNT, CAPT ORDERED TO DON OXYGEN MASKS AND REQUESTED I GET AN IMMEDIATE DSCNT TO 10000 FT MSL. AFTER WE INITIATED DSCNT, I RAN THE EMER PROC FOR CABIN LOSS OF PRESSURIZATION. AS WE WERE PASSING FL240, CABIN ALT CLBED TO 14500 FT AND STARTED TO DROP TO BELOW 9500 FT AT FL200. AS WE LEVELED AT 10000 FT MSL, CABIN PRESSURE READ 9400 FT MSL. WE DID NOT RECEIVE ANY OTHER WARNING THAT THE CABIN WAS CLBING EXCEPT FOR THE COCKPIT VOICE. WE DID NOT RECEIVE A RED MASTER WARNING NOR DID THE CABIN ALT RED WARNING LIGHT ILLUMINATE. OTHER INDICATIONS WERE RECEIVED BY US IN THE COCKPIT. AN UNEVENTFUL LNDG WAS MADE BY THE CAPT AT DFW. NO EMER WAS DECLARED AS ATC PROVIDED US PRIORITY HANDLING AS A ROUTINE REQUEST.

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.