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A DC9 experienced rapid depressurization and an aircraft 90 degree bank simultaneously. The crew declared an emergency and descended.
| Attributes | |
| ACN | 669481 |
| Time | |
| Date | 200508 |
| Local Time Of Day | 0601 To 1200 |
| Place | |
| Locale Reference | airport : zzz.airport |
| State Reference | US |
| Altitude | msl single value : 26000 |
| Environment | |
| Flight Conditions | IMC |
| Light | Night |
| Aircraft 1 | |
| Controlling Facilities | artcc : zzz.artcc |
| Operator | common carrier : air carrier |
| Make Model Name | DC-9 Undifferentiated or Other Model |
| Operating Under FAR Part | Part 121 |
| Flight Phase | descent : intermediate altitude descent : vacating altitude |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | company : air carrier |
| Function | flight crew : captain oversight : pic |
| Qualification | pilot : atp |
| Experience | flight time last 90 days : 38 flight time total : 9900 flight time type : 6000 |
| ASRS Report | 669481 |
| Person 2 | |
| Affiliation | company : air carrier |
| Function | flight crew : first officer |
| Qualification | pilot : atp |
| ASRS Report | 669482 |
| Events | |
| Anomaly | aircraft equipment problem : critical altitude deviation : excursion from assigned altitude other anomaly other anomaly other |
| Independent Detector | other flight crewa other flight crewb |
| Resolutory Action | flight crew : regained aircraft control flight crew : declared emergency flight crew : landed in emergency condition |
| Consequence | faa : assigned or threatened penalties other |
| Supplementary | |
| Problem Areas | Maintenance Human Performance Aircraft Company Flight Crew Human Performance |
| Primary Problem | Aircraft |
Narrative:
During descent from FL320 to 16000 ft; pressurization set for landing at ZZZ; cabin pressure warning came on and at same time; autoplt went into a 90 degree bank. This occurred between FL270-FL260. Prior to this; descent was normal at 2500 FPM and 1-2 EPR. Outside air temperature at FL320 was -12 degrees celsius. In and out the tops no ice on aircraft. Disconnected autoplt and used manual pressurization to recover cabin and aircraft. Went on oxygen during recovery of cabin. Once manual pressurization recovered; the cabin and warnings out. Autoplt worked normally for rest of the flight. Maximum airspeed during descent never went over 310 KTS. But there was a shudder during pressure loss and roll. Upon landing at ZZZ; walk around aircraft found no damage. After talking to maintenance and reviewing aircraft history of automatic pressurization problem. Deferral of automatic pressurization was done. Autoplt worked on leg from ZZZ-ZZZ1 using manual pressurization. Early in the flight; the red iu in the mfd came on. Performed abnormal and warning went away. Callback conversation with reporter revealed the following information: reporter stated that the company mechanics suspected an electrical wiring fault; but did not pinpoint the exact cause. The reporter has been unable to talk with anyone about a final resolution.
Original NASA ASRS Text
Title: A DC9 EXPERIENCED RAPID DEPRESSURIZATION AND AN ACFT 90 DEG BANK SIMULTANEOUSLY. THE CREW DECLARED AN EMER AND DSNDED.
Narrative: DURING DSCNT FROM FL320 TO 16000 FT; PRESSURIZATION SET FOR LNDG AT ZZZ; CABIN PRESSURE WARNING CAME ON AND AT SAME TIME; AUTOPLT WENT INTO A 90 DEG BANK. THIS OCCURRED BTWN FL270-FL260. PRIOR TO THIS; DSCNT WAS NORMAL AT 2500 FPM AND 1-2 EPR. OUTSIDE AIR TEMP AT FL320 WAS -12 DEGS CELSIUS. IN AND OUT THE TOPS NO ICE ON ACFT. DISCONNECTED AUTOPLT AND USED MANUAL PRESSURIZATION TO RECOVER CABIN AND ACFT. WENT ON OXYGEN DURING RECOVERY OF CABIN. ONCE MANUAL PRESSURIZATION RECOVERED; THE CABIN AND WARNINGS OUT. AUTOPLT WORKED NORMALLY FOR REST OF THE FLT. MAX AIRSPD DURING DSCNT NEVER WENT OVER 310 KTS. BUT THERE WAS A SHUDDER DURING PRESSURE LOSS AND ROLL. UPON LNDG AT ZZZ; WALK AROUND ACFT FOUND NO DAMAGE. AFTER TALKING TO MAINT AND REVIEWING ACFT HISTORY OF AUTO PRESSURIZATION PROB. DEFERRAL OF AUTO PRESSURIZATION WAS DONE. AUTOPLT WORKED ON LEG FROM ZZZ-ZZZ1 USING MANUAL PRESSURIZATION. EARLY IN THE FLT; THE RED IU IN THE MFD CAME ON. PERFORMED ABNORMAL AND WARNING WENT AWAY. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR STATED THAT THE COMPANY MECHS SUSPECTED AN ELECTRICAL WIRING FAULT; BUT DID NOT PINPOINT THE EXACT CAUSE. THE RPTR HAS BEEN UNABLE TO TALK WITH ANYONE ABOUT A FINAL RESOLUTION.
Data retrieved from NASA's ASRS site as of January 2009 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.