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ASN Wikibase Occurrence # 233084
Last updated: 19 February 2020
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Date:18-SEP-1970
Time:
Type:Silhouette image of generic B741 model; specific model in this crash may look slightly different
Boeing 747-121
Owner/operator:American Airlines
Registration: N743PA
C/n / msn: 19650/24
Fatalities:Fatalities: 0 / Occupants: 132
Other fatalities:0
Aircraft damage: Minor
Category:Incident
Location:San Francisco's International Airport, CA -   United States of America
Phase: Take off
Nature:Domestic Scheduled Passenger
Departure airport:San Francisco's International Airport, CA
Destination airport:New York-JFK Airport, NY (JFK/KJFK)
Investigating agency: NTSB
Narrative:
American Airlines Flight 14, a Boeing 747-121, N743PA, was a scheduled passenger nonstop flight that originated at San Francisco International Airport. Its
destination was New York, John F. Kennedy International Airport.
Approximately 16 seconds after lift-off at an altitude of 525 feet the No. 1 engine sustained a separation of the second-stage turbine disk rim. The turbine blades and rim fragments penetrated the high-pressure turbine (HPT) case, engine cowling, and adjacent airplane structure. All fluid lines, electrical cables, and pneumatic ducts located in the pylon area were severed and an intense fire ensued. Two fuel tank access plates on the bottom of the wing inboard of No. 1 pylon were also penetrated by turbine fragments.

The fire warning for the No. 1 engine came on simultaneously with the engine explosion. Emergency fire control procedures were initiated and executed. The fire, which was observed by the captain, was propagating over the top of the left wing and lasted approximately 3 minutes. As a result of complete failure of the No. 1 hydraulic system, alternate extension of the body main landing gear, nose landing gear, and inboard trailing edge flaps was necessary. A successful landing was accomplished on San Francisco's International Airport. Passengers and crewmembers were deplaned on the taxiway by means of boarding steps. There were no injuries to passengers, crewmembers, or persons on the ground.

The National Transportation Safety Board determines that the probable cause of this incident was a progressive failure in the high-pressure turbine
module in the No. 1 JT9D-3A engine. This failure was initiated by the undetected stress rupture fractures of several first-stage turbine blades and culminated in in-flight separation of the second-stage turbine disk rim.

Sources:

NTSB

Accident investigation:
cover
  
Investigating agency: NTSB
Status: Investigation completed
Duration:
Download report: Final report


Images:

Photo of N743PA courtesy AirHistory.net


London - Heathrow (EGLL / LHR)
28 August 1971; (c) Stephen Rendle

Revision history:

Date/timeContributorUpdates
19-Feb-2020 18:01 harro Added

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