DCA15LA067

NTSB accident investigation · Boeing 767 · Honolulu (Pacific Ocean) · February 15, 2015

Accident · Serious injuriesLimited investigationFinal report
Date
February 15, 2015, 01:03 UTC
Place
Honolulu (Pacific Ocean)
Injuries
1 serious, 4 minor, 245 uninjured
Damage
No damage
Phase of flight
Enroute
Aircraft
N59053Boeing 767
Defining event
Enroute: Turbulence encounter
Weather
Instrument (IMC) · Day
Status
Completed · report June 8, 2020
Report
Approved by Office Director
NTSB office
Major Investigations Division
Parties
FAA
Case key
90744

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

On this page

Probable cause

an encounter with convective turbulence associated with a forecasted area of thunderstorms.

Findings · 1

NTSB’s coded findings. Those marked are part of the probable cause; the rest are factors or other findings. Under each, the cases with the same finding.

Turbulence: convective turbulenceEnvironmental issues › Conditions/weather/phenomena · Effect on personnelBoeing 767-424ER: 1 caseAll aircraft: 145 casesProbable cause

Sequence of events

The events NTSB coded, in order, by phase of flight. The defining event is the one that best describes the accident. Under each, the cases with the same event anywhere in their sequence.

Analysis

On February 15, 2015, about 0103 coordinated universal time, United Airlines flight 15, a Boeing 767-400ER, N59053, encountered severe turbulence over the Pacific Ocean while enroute to Honolulu International Airport (HNL), Honolulu, Hawaii. Of the 250 passengers and crew onboard, one flight attendant was seriously injured, and three flight attendants and one passenger sustained minor injuries. The airplane was not damaged. The flight was operating under 14 Code of Federal Regulations Part 121 as a regularly scheduled passenger flight from Newark Liberty International Airport (EWR), Newark, New Jersey, to HNL. The flight was uneventful from EWR across the continental United States. Once over the Pacific Ocean, the flight received an ACARS message from dispatch advising of an area of possible embedded thunderstorms. The flight experienced light to moderate turbulence for most of the remaining flight, which required the seat belt sign to remain on most of the time. About an hour from HNL, the captain returned early from his crew rest time because he noticed that the flight was encountering areas of moderate turbulence. Prior to entering the flight deck, the captain noticed that the flight attendants (FA) were seated in their jumpseats and advised the lead FA to not conduct the final service and remain seated. Shortly after retaking the left seat, and as the flight was passing immediately south of a line of embedded of the forecasted thunderstorms, the captain requested a descent from their cruising altitude of flight level (FL)360 to FL240. The flight crew reported they were in instrument meteorological conditions with precipitation during the descent. The weather radar was on and the seatbelt sign was illuminated. The flight encountered an area of severe turbulence for about 30 seconds as it was descending through FL254. The flight data recorder data indicate that the vertical acceleration fluctuated between about -0.17 g's and +1.62 g's, the lateral acceleration fluctuated between about -0.09 g's and +0.11 g's, and the roll fluctuated between about 5° left and 12° right. At the time of the turbulence, the FAs were securing the galleys, preparing the cabin for landing, and distributing agriculture documents. Four flight attendants (FA) in the aft galley were thrown against the ceiling and back to the floor, injuring all four. After being notified of the serious injuries, the flight crew declared an emergency with air traffic control and arranged for medical personnel to meet the aircraft at HNL. The four flight attendants were transported to the hospital where one flight attendant was diagnosed with a fractured arm and the other three were released with minor injuries. After landing the crew were notified by a passenger that their child had suffered a bloody nose, who was treated but not transported to the hospital.

Factual narrative

On February 15, 2015, about 0103 coordinated universal time, United Airlines flight 15, a Boeing 767-400ER, N59053, encountered severe turbulence over the Pacific Ocean while enroute to Honolulu International Airport (HNL), Honolulu, Hawaii. Of the 250 passengers and crew onboard, one flight attendant was seriously injured, and three flight attendants and one passenger sustained minor injuries. The airplane was not damaged. The flight was operating under 14 Code of Federal Regulations Part 121 as a regularly scheduled passenger flight from Newark Liberty International Airport (EWR), Newark, New Jersey, to HNL. The flight was uneventful from EWR across the continental United States. Once over the Pacific Ocean, the flight received an ACARS message from dispatch advising of an area of possible embedded thunderstorms. The flight experienced light to moderate turbulence for most of the remaining flight, which required the seat belt sign to remain on most of the time. About an hour from HNL, the captain returned early from his crew rest time because he noticed that the flight was encountering areas of moderate turbulence. Prior to entering the flight deck, the captain noticed that the flight attendants (FA) were seated in their jumpseats and advised the lead FA to not conduct the final service and remain seated. Shortly after retaking the left seat, and as the flight was passing immediately south of a line of embedded of the forecasted thunderstorms, the captain requested a descent from their cruising altitude of flight level (FL)360 to FL240. The flight crew reported they were in instrument meteorological conditions with precipitation during the descent. The weather radar was on and the seatbelt sign was illuminated. The flight encountered an area of severe turbulence for about 30 seconds as it was descending through FL254. The flight data recorder data indicate that the vertical acceleration fluctuated between about -0.17 g's and +1.62 g's, the lateral acceleration fluctuated between about -0.09 g's and +0.11 g's, and the roll fluctuated between about 5° left and 12° right. At the time of the turbulence, the FAs were securing the galleys, preparing the cabin for landing, and distributing agriculture documents. Four flight attendants (FA) in the aft galley were thrown against the ceiling and back to the floor, injuring all four. After being notified of the serious injuries, the flight crew declared an emergency with air traffic control and arranged for medical personnel to meet the aircraft at HNL. The four flight attendants were transported to the hospital where one flight attendant was diagnosed with a fractured arm and the other three were released with minor injuries. After landing the crew were notified by a passenger that their child had suffered a bloody nose, who was treated but not transported to the hospital.

Aircraft

Registration
N59053
Reported as
Boeing 767 (400ER)
Category
Airplane
Serial number
29448
Built
2000
Airframe hours
63,732
Damage
No damage
Flight
Part 121
Operator
United Air Lines Inc
Registered owner
United Airlines Inc
Airworthiness certificate
Standard, Transport
Last inspection
Continuous airworthiness · February 14, 2015
Departed
KEWR · Newark, NJ
Destination
KHNL · Honolulu, HI
Flight plan
IFR
Equipment
Onboard weather, Data recorder, Auto-pilot, Stall warning system

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 · 2

As NTSB recorded them. NTSB leaves out names.

Role
Pilot
Age
61
Injuries
None
Certificate
Airline transport
Airplane ratings
Multi-engine land, Single-engine land
Instrument ratings
Airplane
Medical
Class 1, With waivers/limitations
Last flight review
June 11, 2014
Seat
Left
Restraint
5-point
Flight hours
30,000 total · 6,000 in this make and model · 168 in the last 90 days · 40 in the last 30 days · 10 in the last 24 hours
Role
Co-pilot
Age
51
Injuries
None
Certificates
Airline transport, Commercial, Flight engineer
Airplane ratings
Single-engine land, Multi-engine land
Instrument ratings
Helicopter, Airplane
Medical
Class 1, With waivers/limitations
Last flight review
January 4, 2014
Seat
Right
Restraint
Lap only
Flight hours
15,000 total · 7,500 in this make and model · 6,000 as pilot in command · 225 in the last 90 days · 80 in the last 30 days · 10 in the last 24 hours

Weather

Conditions
Instrument (IMC) · Day
Wind
257° at 97 knots
Temperature
-13 °F
Altimeter
29.92 inHg
Turbulence
Severe

Docket · 3

The files NTSB released with the investigation on July 14, 2020, on NTSB’s docket system: statements, records, photos and specialists’ reports. 2.9 MB in all.