Air carrier medium large transport loss of cabin pressure. Emergency descent.

Attributes
ACN	97776
Time
Date	198811
Day	Thu
Local Time Of Day	1801 To 2400
Place
Locale Reference	atc facility : jax
State Reference	FL
Altitude	msl bound lower : 26000 msl bound upper : 26000
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Controlling Facilities	artcc : zjx tower : bna
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Flight Phase	climbout : intermediate altitude
Route In Use	enroute airway : j53
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 180 flight time total : 8000 flight time type : 3000
ASRS Report	97776
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 210 flight time total : 9000 flight time type : 400
ASRS Report	99815
Events
Anomaly	aircraft equipment problem : critical other anomaly other
Independent Detector	other flight crewa
Resolutory Action	flight crew : declared emergency other
Consequence	faa : investigated other
Supplementary
Primary Problem	Aircraft

Narrative:

We departed mlb at XA19 local. Passing 26000' during climb we heard a vibration as if something was flapping against the side of the aircraft. Shortly after that the cabin rate of climb indicator was pegged at 6000 FPM rate of climb. We were unable to control the pressure, so we put on the O2 masks--ran the depressurization checklist, declared an emergency, and requested vectors for jacksonville. We requested the emergency equipment to standby for our arrival. We made an uneventful landing at jacksonville airport at XB20 and requested that the medical team meet us at the gate. One woman was hospitalized that had a previous heart condition. The cause of the pressure problem appears to be the bottom of the forward cargo door seal that came off. Jacksonville center, approach control and tower all did an excellent job of handling this problem. Supplemental information from acn 99815: heard a rumpling noise. Thinking it was a possible nose gear door hanging cycled gear handle from 'off' to 'up', then back to the 'off' position with no noticeable change of noise. Unable to control cabin. Accomplished emergency descent/rapid decompression checklist, declared an emergency and landed uneventfully. To prevent a recurrence, the ground agent could visually inspect all exterior doors (cargo, service) for security prior to pushing back the airplane.

Original NASA ASRS Text

Title: ACR MLG LOSS OF CABIN PRESSURE. EMERGENCY DESCENT.

Narrative: WE DEPARTED MLB AT XA19 LCL. PASSING 26000' DURING CLB WE HEARD A VIBRATION AS IF SOMETHING WAS FLAPPING AGAINST THE SIDE OF THE ACFT. SHORTLY AFTER THAT THE CABIN RATE OF CLB INDICATOR WAS PEGGED AT 6000 FPM RATE OF CLB. WE WERE UNABLE TO CONTROL THE PRESSURE, SO WE PUT ON THE O2 MASKS--RAN THE DEPRESSURIZATION CHKLIST, DECLARED AN EMER, AND REQUESTED VECTORS FOR JACKSONVILLE. WE REQUESTED THE EMER EQUIP TO STANDBY FOR OUR ARR. WE MADE AN UNEVENTFUL LNDG AT JACKSONVILLE ARPT AT XB20 AND REQUESTED THAT THE MEDICAL TEAM MEET US AT THE GATE. ONE WOMAN WAS HOSPITALIZED THAT HAD A PREVIOUS HEART CONDITION. THE CAUSE OF THE PRESSURE PROB APPEARS TO BE THE BOTTOM OF THE FORWARD CARGO DOOR SEAL THAT CAME OFF. JACKSONVILLE CENTER, APCH CTL AND TWR ALL DID AN EXCELLENT JOB OF HANDLING THIS PROB. SUPPLEMENTAL INFO FROM ACN 99815: HEARD A RUMPLING NOISE. THINKING IT WAS A POSSIBLE NOSE GEAR DOOR HANGING CYCLED GEAR HANDLE FROM 'OFF' TO 'UP', THEN BACK TO THE 'OFF' POS WITH NO NOTICEABLE CHANGE OF NOISE. UNABLE TO CONTROL CABIN. ACCOMPLISHED EMER DSCNT/RAPID DECOMPRESSION CHKLIST, DECLARED AN EMER AND LANDED UNEVENTFULLY. TO PREVENT A RECURRENCE, THE GND AGENT COULD VISUALLY INSPECT ALL EXTERIOR DOORS (CARGO, SVC) FOR SECURITY PRIOR TO PUSHING BACK THE AIRPLANE.

Data retrieved from NASA's ASRS site as of August 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.