Event Details


Title:Turbulence injury, Boeing 777, July 25, 2004
Micro summary:This Boeing 777 experienced turbulence while in cruise, fracturing a flight attendant's shoulder.
Event Time:2004-07-25 at 0115 EDT
File Name:2004-07-25-US.pdf
Publishing Agency:National Transportation Safety Board (NTSB)
Publishing Country:USA
Report number:DCA04MA061
Pages:6
Site of event:Miami, FL
Departure:Miami International Airport, Miami, Florida, USA
Destination:Guarulhos International Airport, So Paulo, So Paulo, Brazil
Airplane Type(s):Boeing 777
Flight Phase:Cruise
Registration(s):N797AN
Operator(s):American Airlines
Type of flight:Revenue
Occupants:217
Fatalities:
Serious Injuries:1
Minor/Non-Injured:216
Other Injuries:0
Executive Summary:

NTSB short summary:

the in-flight encounter with unforecasted clear air turbulence.

NTSB synopsis:

The flight encountered unforecasted clear air turbulence while the flight attendants were providing meal service to the passengers. Several of the flight attendants were thrown to the floor by the turbulence, and a flight attendant operating in the rear of the airplane received a fractured left shoulder. The autopilot was engaged at the time of the event, and there were no pilot inputs during the turbulence encounter. Statements from the captain (the flying pilot) and the first officer indicated that the event involved clear air turbulence that lasted 3-4 seconds. The captain characterized the turbulence encounter as "moderate" and being similar to a wake turbulence encounter because of the extremely short duration. He indicated that there were no aircraft in front of them and the nearest thunderstorms were greater than 20 miles to the northwest. The first officer added that they had received no turbulence warnings from other aircraft and that they were clear of all weather.

NTSB factual narrative text:

On July 25, 2004, about 0115 eastern daylight time (EDT), American Airlines flight 955, a Boeing 777, N797AN, encountered clear air turbulence during cruise at flight level (FL) 370 approximately 25 nautical miles north of intersection GELOG. Flight 955 was a regularly scheduled international passenger flight from Miami International Airport, Miami, Florida, to Sao Paulo, Brazil (GRU), with 204 passengers and 13 crewmembers on board. During the turbulence encounter, one of the flight attendants suffered a fractured shoulder. The flight continued to GRU, where the injured flight attendant was transported to a hospital. The flight was operated under 14 Code of Federal Regulations Part 121 under an instrument flight plan.

At the time of the turbulence encounter, which occurred about an hour after takeoff, flight attendants were providing meal service to the passengers. Statements from the flight attendants characterized the turbulence as "bad" or "severe" and indicated that there were at least two jolts that threw them to the floor. The injured flight attendant, who was located in the rear of the airplane, stated that she tried to hold onto an armrest in the last row after the initial jolt threw her down. She was tossed up and then down as the turbulence continued, and her shoulder struck one of the armrests. Two doctors responded to a request for help, and the injured flight attendant was treated with pain medication, ice packs, and a sling. The captain decided to continue to GRU after the doctors attended to the flight attendant and arranged for her to be transported to a hospital. The flight continued for approximately 6 hours before landing at GRU. The flight attendant was diagnosed with a fractured left shoulder.

Statements from the captain (the flying pilot) and the first officer indicated that the event involved clear air turbulence that lasted 3-4 seconds. The captain characterized the turbulence encounter as "moderate" and being similar to a wake turbulence encounter because of the extremely short duration. He indicated that there were no aircraft in front of them and the nearest thunderstorms were greater than 20 miles to the northwest. The first officer added that they had received no turbulence warnings from other aircraft and that they were clear of all weather.

The reserve pilot for the flight stated that he had been resting in the designated crew rest seat in first class at the time of the event. He stated that the turbulence lasted less than five seconds and involved approximately two groups of three rapid and abrupt jolts that appeared to diminish in severity over time. He indicated that the flight conditions were mostly smooth before and shortly after the event.

The seat belt sign was on at the time of the turbulence. There was no forecast turbulence for the entire route of the flight.

Flight Recorder Data

A review of the flight data recorder (FDR) data indicates that the turbulence event lasted about 10 seconds. The data further show the following about the turbulence encounter:

- there was a 60-degree change in wind direction and a +/-8 knot change in wind speed;
- the autopilot and yaw damper remained engaged and active throughout the event; (According to information provided by Boeing, the B-777's primary flight computer will disconnect the autopilot when it is overridden by manual inputs.)
- there were angle of attack deviations of +/- 3 degrees;
- there were airspeed deviations of -12 to +15 knots; and
- vertical accelerations ranged from approximately 1.6 g's to 0.2 g's; lateral accelerations ranged from approximately 0.06 g's to -0.2 g's; and longitudinal accelerations (which averaged about 0.04 g's prior to the event) ranged from approximately 0.06 g's to -0.01 g's.




Learning Keywords:Operations - Turbulence
Consequence - Flight Attendant Fatality - Injury
Close match:Turbulence, Report on the accident to Airbus A330-342 B-HYA within the Manila Flight Information Region on 18 July 2003
Accident involving turbulence and Aer Arann ATR-42-300 on descent to Donegal International Airport, Ireland, on December 2, 2001
Turbulence injuries, Boeing 747-443, G-VROM
Turbulence injuries, Boeing 777-236, G-VIIO
Turbulence injuries, Airbus A300B4-605R, G-MONR
Severe turbulence, Boeing 777-236, G-YMME
Turbulence, Boeing 747-436, G-CIVP
Turbulence injuries, Boeing 777-200, N786UA
Turbulence injury, Boeing 777, April 25, 2006
Turbulence injury, Boeing 757-223, June 5, 2005
Turbulence injury, Boeing 737-700, April 29, 2005
Turbulence injury, Boeing 767-232, September 29, 2004
Turbulence injury, Airbus A319, July 17, 2004
Turbulence injury, McDonnell Douglas DC-9-82, July 15, 2004
Turbulence injury, Boeing 737-7H4, June 4, 2004
Turbulence injury, McDonnell Douglas DC-9-82, May 26, 2004
Turbulence injury, Boeing 767-300, April 10, 2004
Turbulence injury, Boeing 757-200, March 1, 2004
Turbulence injuries, Boeing 737-500, November 1, 2003
Turbulence injuries, Pan American World Airways, Inc., Boeing 747-121, N739PA, near Nantucket, Massachusetts, November 4, 1970
Turbulence, Northwest Airlines, Inc., Boeing 747-151, N606US, Over the North Pacific Ocean, 105 Nautical Miles West of 150 East Longitude at 36 North Latitude, April 12, 1972
Turbulence injuries, National Airlines, Inc., Boeing 747-135, N77772, Near Lake Charles, Louisiana, January 4, 1972
Turbulence injuries, Air France, Boeing 707-B-328B, F-BLCA, Near O-Neill, Nebraska, May 13, 1974
Turbulence injuries, Air Canada Flight 965, Lockheed L-1011, C-FTNJ, Near Charleston, South Carolina, November 24, 1983
Turbulence injury, Boeing 757-232, September 15, 1993
Turbulence injury, Boeing 747-400, February 12, 1994
Turbulence on descent involving a Boeing 737-790, near Anchroage, Alaska, on November 13, 2000
Turbulence injuries, Boeing 737-400, December 22, 1996
Turbulence injuries, Boeing 727-200, July 28, 2000
Turbulence injuries, Boeing 737-200, April 17, 2001
Turbulence injury, Boeing 757-200, May 29, 2002
Turbulence injury, McDonnell Douglas DC-9-82, November 6, 2002
Turbulence injuries, Boeing 727-200, March 16, 1995
Turbulence injuries, Boeing 737-200, April 28, 1997
Turbulence injuries, McDonnell Douglas DC-9-80, February 8, 1999
Turbulence injury, Boeing 777-223, August 22, 2000
Turbulence injuries, Boeing 757-200, April 18, 2002
Turbulence injuries, Boeing 757-222, April 21, 2003
Turbulence injury, Airbus A319-111, June 2, 2003
Turbulence injuries, Boeing 777-222, June 11, 1999
Turbulence injuries, McDonnell Douglas DC-9-81, August 7, 2003
Turbulence injuries, Boeing 737-201, June 22, 1996
Turbulence injuries, Boeing 767-222, June 20, 1995
Turbulence injuries, Boeing 757, August 4, 1995
Turbulence injury, McDonnell Douglas DC-9-51, January 28, 1997
Turbulence injuries, Boeing 747-422, September 14, 1997
Turbulence injuries, Boeing 767-223, July 22, 1998
Turbulence injuries, Boeing 737-222, May 5, 1999
Turbulence injuries, McDonnell Douglas DC-10-30, March 22, 2002
Turbulence injury, Boeing 757-2B7, May 24, 1998
Turbulence injury, Boeing 737-3H4, June 25, 1999
Turbulence injury, Boeing 757-223, April 7, 1996
Turbulence injuries, Boeing 737-824, July 8, 1999
Turbulence injury, Boeing 757-2G7, January 11, 2000
Turbulence Injury, Boeing 757-2G7, April 2, 2000
Turbulence injury, Airbus A320-232, April 19, 2001
Turbulence injury, Boeing 737-500, August 9, 2001
Turbulence injury, Boeing 747-422, May 1, 2002
Turbulence injury, McDonnell Douglas MD-82, June 12, 2003
Turbulence injuries, Boeing 747-422, October 17, 1995
Turbulence injury, Boeing 747-122, November 1, 1995
Turbulence injury, Boeing 747-422, November 19, 1996
Turbulence injury, December 22, 1996
Turbulence injuries, Boeing 737-242C, March 4, 1998
Turbulence injury, Boeing 737-300, December 13, 1998
Turbulence on descent, Airbus A320-231, September 16, 1999
Turbulence injuries, Boeing 767-332ER, September 20, 2000
Turbulence injury, Boeing 757-2G7, May 28, 2001
Turbulence injury, Airbus A320-232, August 20, 2001
Turbulence on descent, Boeing 777-223, February 25, 2003
Turbulence injury, McDonnell Douglas MD-88, Janaury 6, 1995
Turbulence injury, McDonnell Douglas DC-9-82, October 1, 1997
Turbulence injury, Boeing 737-724, February 19, 2002
Turbulence injury, Boeing 767-224, April 22, 2002
Turbulence injury, Boeing 767-300, May 7, 2003
Turbulence injury, Boeing 737-800, August 16, 2003
Turbulence injury, Airbus A300B4-605R, January 7, 1997
Turbulence injury, Boeing 747-200, April 18, 1998
Turbulence injury, Bombardier DHC-8-102, September 27, 1998
Turbulence injury, September 30, 1999
Turbulence injuries, Boeing 767-332ER, November 4, 2000
Turbulence injury, Boeing 737-522, November 25, 1995
Turbulence injury, Boeing 737-2H4, July 7, 1994
Turbulence injury, Boeing 737-291A, June 11, 1997
Tubulence, December 28, 1997, Boeing 747-122, December 28, 1997
Turbulence injuries, Boeing 777-236, G-VIIP, May 14, 2006
Turbulence injuries, Airbus A340-300, D-AIGK, September 18, 1996
Turbulence injuries, Boeing 757-2Q8, N755AT, March 2, 1997
Turbulence injuries, Airbus A340-300, D-AIGK, August 6, 2003

 




Accident Reports on DVD, Copyright © 2006 by Flight Simulation Systems, LLC.  All Rights Reserved.
 All referenced trademarks are the property of their respective owners.
www.fss.aero