Event Details


Title:Turbulence injuries, Boeing 777-222, June 11, 1999
Micro summary:This Boeing 777-222 encountered turbulence while in descent. Several people received injuries.
Event Time:1999-06-11 at 2118 CDT
File Name:1999-06-11-US.pdf
Publishing Agency:National Transportation Safety Board (NTSB)
Publishing Country:USA
Report number:CHI99LA184
Pages:5
Diversion Airport:Minneapolis St Paul International, Minneapolis,Mn., Minnesota, USA
Site of event:Madison, WI
Departure:Minneapolis St Paul International, Minneapolis,Mn., Minnesota, USA
Destination:O'Hare International Airport, Chicago, Illinois, USA
Airplane Type(s):Boeing 777-222
Flight Phase:Descent
Registration(s):N781UA
Operator(s):United Airlines
Type of flight:Revenue
Occupants:296
Fatalities:0
Serious Injuries:1
Minor/Non-Injured:295
Other Injuries:0
Diverted to:Minneapolis St Paul International, Minneapolis,Mn., Minnesota, USA
Executive Summary:

NTSB short summary:

the pilot-in-command's inadequate evaluation of the weather conditions. Factors associated with the accident were the turbulence encountered and the seat belt sign was not illuminated.

NTSB synopsis:

While en route from Minneapolis to Chicago the flight encountered turbulence at 19,680 feet msl while in a descent. Four passengers and four flight attendants received minor injuries. One passenger received a broken ankle. The flight had diverted to Minneapolis due to thunderstorm activity in the Chicago area. The captain reported the flight was smooth up until the unexpected turbulence was encountered. The seat belt sign was not on at the time of the encounter. The flight crew received a Weather Briefing Message (WBM) prior to departing Minneapolis, which contained convective sigmets for Wisconsin, Illinois, and Indiana. The accident took place ahead of a stationary front which extended northeast-southwest through central Wisconsin and Iowa which had been creating shower and thunderstorm activity throughout afternoon and evening on the day of the accident. A review of the data from the Quick Access Recorder revealed the flight experienced a change in G-loading from .0843 g's to 1.9375 g's over a 2-second time period while at an altitude of 19,680 feet msl.

NTSB factual narrative text:

On June 11, 1999, at 2118 central daylight time (cdt), a Boeing 777-222, N781UA, operated by United Airlines as flight 256 encountered turbulence during a descent near Madison, Wisconsin. Four passengers received minor injuries and one passenger was seriously injured. Four flight attendants received minor injuries. Both cockpit crewmembers, 6 flight attendants, and 279 passengers were not injured. The airplane was not damaged. The 14 CFR Part 121 passenger flight was operating in visual meteorological conditions on an IFR flight plan.

The flight was originally scheduled from Denver, Colorado, to Chicago, Illinois; however, it diverted to Minneapolis, Minnesota due to thunderstorms in the Chicago area. The flight departed from Minneapolis, Minnesota, at 2048 cdt. The flight continued on to Chicago after the turbulence encounter where it landed uneventfully, at the Chicago O'Hare International Airport, at 2149 cdt.

The captain reported the flight was smooth up until the unexpected turbulence was encountered while they were descending through 18,000 feet msl. He reported the moderate turbulence lasted 20 to 30 seconds after which the remainder of the flight was smooth. The seat belt sign was not on at the time of the turbulence encounter. The captain reported the radar was on and it was showing no indication of cells or turbulence along the route. He reported there was a rain shower at their 2 o'clock position, 30 miles away.

The first officer reported that moderate turbulence was encountered during the descent at an altitude of about 17,000 feet msl. He reported, "It consisted of a 2-3 second period of negative "g" followed by a 2-3 second positive "g" deviation, then a two to five minute period of light to moderate slight deviations from our flight path." He reported there was nothing on the radar in their area, but convective activity was displayed beyond the Chicago area.

The flight attendants reported that all the passengers that were injured were out of their seats and in the back of the airplane when the turbulence was encountered. The most serious injury was a passenger who suffered a broken ankle.

According to United Airlines, the flight crew received a Weather Briefing Message (WBM) prior to departing Minneapolis, which contained convective sigmets for Wisconsin, Illinois, and Indiana. The accident took place ahead of a stationary front which extended northeast-southwest through central Wisconsin and Iowa which had been creating shower and thunderstorm activity throughout afternoon and evening on the day of the accident.

A review of recorded aircraft data revealed the flight experienced a change in G-loading from .0843 g's to 1.9375 g's over a 2-second time period while at an altitude of 19,680 feet msl.
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, Boeing 777, July 25, 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, 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