Accident Boeing 747-121 N747PA,

ASN Wikibase Occurrence # 330757

Date:	Friday 30 July 1971
Time:	15:29
Type:	Boeing 747-121
Owner/operator:	Pan American World Airways (Pan Am)
Registration:	N747PA
MSN:	19639/2
Year of manufacture:	1969
Total airframe hrs:	2898 hours
Engine model:	Pratt & Whitney JT9D-3A
Fatalities:	Fatalities: 0 / Occupants: 218
Aircraft damage:	Substantial, repaired
Category:	Accident
Location:	San Francisco International Airport, CA (SFO) - United States of America
Phase:	Initial climb
Nature:	Passenger - Scheduled
Departure airport:	San Francisco International Airport, CA (SFO/KSFO)
Destination airport:	Tokyo (unknown airport)
Investigating agency:	NTSB
Confidence Rating:	Accident investigation report completed and information captured

Narrative:
The Pan American Boeing 747 struck the Approach Light Structure (ALS) at the departure end of runway 01R while taking off from the San Francisco International Airport. Two passengers, in seats 47G and 48G, were seriously injured by parts of the Approach Light System structure which penetrated the
passenger compartment. The flightcrew continued the takeoff and then flew the aircraft for 1 hour and 42 minutes while assessing the structural damage and dumping fuel before landing on runway 28L. After landing, the aircraft veered off the right side of runway 28L and came to a stop in the unpaved area approximately 5,300 feet from the approach end of the runway. The passengers and crew evacuated the aircraft using the emergency evacuation slides.
Upon activation of the slides for evacuation, four of the 10 passenger slides failed to function properly and were not useable. During the evacuation the aircraft tilted slowly back onto the rear section of the fuselage.
The aircraft had been dispatched for a departure from a closed runway and, upon changing to an open runway, the crew did not recompute the proper reference speeds for takeoff under the existing conditions.

PROBABLE CAUSE: "The National Transportation Safety Board determines that the probable cause of this accident was the pilots use of incorrect takeoff
reference speeds. This resulted from a series of irregularities involving: (1) the collection and dissemination of airport information; (2) aircraft dispatching; and (3) crew management and discipline; which collectively rendered ineffective the air carriers operational control system."

Accident investigation: