LAX94LA141

NTSB accident investigation · Boeing 747-400 · Pacific Ocean (Pacific Ocean) · February 12, 1994

Accident · Serious injuriesLimited investigationFinal report
Date
February 12, 1994
Place
Pacific Ocean (Pacific Ocean)
Injuries
1 serious, 408 uninjured
Damage
No damage
Phase of flight
Enroute
Aircraft
N186UABoeing 747-400
Weather
Visual (VMC) · Night/dark
Status
Completed · report November 14, 1994
Report
Approved by Office Director
FAA report
19940212014219A
Case key
28679

From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.

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Probable cause

the failure of the chief steward to verify that all flight attendants had been informed, and were complying with the captain's instructions to remain seated with their seatbelts fastened.

Sequence of events

NTSB’s coding before 2008: each occurrence and phase of flight, and the causes and factors under it. The codes are defined in NTSB’s coding manual.

In flight encounter with weatherCruise - normal
Weather condition - turbulence,clear airFactor
Instructions,written/verbal - not issuedOther crewmemberCause
Miscellaneous/otherCruise - normal
Seat belt - not usedFlight attendantCause

Analysis

The airliner was on an authorized off-course deviation, approaching MEGOG intersection, to circumvent some convective activity which had been identified on radar. As a precaution, the 'fasten seatbelt' light was illuminated and the captain told the chief purser to advise the other flight attendants of possible turbulence and to be seated. Approximately ten minutes later at MEGOG intersection, the aircraft encountered three to five seconds of what the captain described as moderate-to-severe turbulence. The weather radar was on at the time of the of the actual encounter; however, there were no weather returns showing on the scope. During the turbulence, one flight attendant who did not get the prewarning was answering a passenger call, and was not seated. Passenger reports indicate that, at the onset, the flight attendant left the floor of the aircraft and came back down hard on her shoulder and side. It was later determined that the flight attendant suffered a hairline fracture of the right clavicle.

Factual narrative

On February 12, 1994, about 1345 coordinated universal time, a Boeing 747-400, N186UA, encountered clear air turbulence at flight level FL350 while in cruise over the Pacific Ocean at a position W 157.00 by S 010.03.4. During the encounter, one of the flight attendants fell, sustaining a fractured right clavicle. The aircraft was operated by United Airlines, Inc., as flight 841, a scheduled international passenger flight from Los Angeles, California, to Auckland, New Zealand, under the provisions of 14 CFR Part 121 of the Federal Aviation Regulations. The aircraft was not damaged. One flight attendant sustained serious injuries; however, the remaining 408 passengers and crewmembers were not injured. The flight originated at Los Angeles, California, on the day of the mishap at 0626 Pacific standard time as a nonstop flight to New Zealand.

According to United Airlines, the aircraft was on an authorized off-course deviation, approaching MEGOG intersection, to circumvent some convective activity which had been identified on radar. As a precaution, the "fasten seatbelt" light was illuminated and the captain told the chief purser to advise the other flight attendants of possible turbulence and to be seated. Approximately ten minutes later at MEGOG intersection, the aircraft encountered three to five seconds of what the captain described as moderate-to-severe turbulence. The weather radar was on at the time of the actual encounter; however, there were no weather returns showing on the scope. During the turbulence, one flight attendant who did not get the prewarning was answering a passenger call, and was not seated. Passenger reports indicate that, at the onset the flight, attendant left the floor of the aircraft and came back down hard on her shoulder and side. It was later determined that the flight attendant suffered a hairline fracture of the right clavicle.

Aircraft

Registration
N186UA
Reported as
Boeing 747-400
Category
Airplane
Serial number
26875
Airframe hours
5,917
Engine
P&W PW4056, 56,000 lbs thrust, turbo fan
Damage
No damage
Flight
Part 121
Operator
United Airlines
Registered owner
United Airlines
Airworthiness certificate
Standard, Transport
Last inspection
Continuous airworthiness · November 17, 1993 · 1,265 hours before
Departed
LAX · Los Angeles, CA
Destination
PAKL · Auckland
Flight plan
IFR

Matched to the registry by N-number and the event date; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.

Flight crew

As NTSB recorded them. NTSB leaves out names.

Role
Pilot
Age
54
Certificates
Commercial, Airline transport, Flight engineer
Airplane ratings
Multi-engine land, Single-engine sea, Single-engine land
Medical
Class 1, Valid Medical--no waivers/lim.
Seat
Left
Flight hours
15,397 total · 1,110 in this make and model

Weather

Conditions
Visual (VMC) · Night/dark

FAA reports on this event · 1

The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.