Accident Boeing 737-3H4 (WL) N632SW, Friday 1 April 2011
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Date:Friday 1 April 2011
Type:Silhouette image of generic B733 model; specific model in this crash may look slightly different    
Boeing 737-3H4 (WL)
Owner/operator:Southwest Airlines
Registration: N632SW
MSN: 27707/2799
Year of manufacture:1996
Total airframe hrs:48748 hours
Cycles:39786 flights
Engine model:CFMI CFM56-3B1
Fatalities:Fatalities: 0 / Occupants: 122
Other fatalities:0
Aircraft damage: Minor, repaired
Location:Yuma International Airport, AZ (YUM) -   United States of America
Phase: En route
Nature:Passenger - Scheduled
Departure airport:Phoenix-Sky Harbor International Airport, AZ (PHX/KPHX)
Destination airport:Sacramento International Airport, CA (SMF/KSMF)
Investigating agency: NTSB
Confidence Rating: Accident investigation report completed and information captured
Southwest Airlines Flight 812, from Phoenix-Sky Harbor International Airport, AZ (PHX) to Sacramento International Airport, CA (SMF), diverted to Yuma International Airport, AZ (YUM) after experiencing a rapid depressurization at approximately 34,000 feet.
Upon landing, a 5-foot x 1-foot hole in the crown area was observed on the left side of the airplane, aft of the over-wing exit at the stringer 4L lap joint. Of the 117 passengers and 5 crew members onboard, one flight attendant received a minor injury.
Flightaware data indicate the flight was climbing through about FL344 at 15:57 when the incident happened. It landed at Yuma 16:23.

PROBABLE CAUSE: "The National Transportation Safety Board determines that the probable cause of this accident was the improper installation of the fuselage crown skin panel at the S-4L lap joint during the manufacturing process, which resulted in multiple site damage fatigue cracking and eventual failure of the lower skin panel. Contributing to the injuries was flight attendant A's incorrect assessment of his time of useful consciousness, which led to his failure to follow procedures requiring immediate donning of an oxygen mask when cabin pressure is lost."

Accident investigation:
Investigating agency: NTSB
Report number: NTSB/AAB-13/02
Status: Investigation completed
Duration: 2 years and 11 months
Download report: Final report


Southwest Airlines statement
Flightaware track


photo (c) NTSB; Yuma International Airport, AZ (YUM); April 2011; (publicdomain)

photo (c) NTSB; Yuma International Airport, AZ (YUM); April 2011; (publicdomain)

photo (c) Vegasrails; Las Vegas-McCarran International Airport, NV (LAS/KLAS); 2000

Revision history:


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