Boeing 777-222 N781UA

Summary

On 12 June 1999 at about 02:18 local time, a Boeing 777-222 registered N781UA was involved in an accident near Madison, Wisconsin, United States. 296 people were on board and one was seriously injured, 8 had minor injuries. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

12 June 1999 at 02:18

Classification

Accident

Location

Madison, Wisconsin, United States

Coordinates

43.0568, -89.4040

Aircraft

Boeing 777-222

Registration

N781UA

Category

Airplane

Engines

2

Operator

Not recorded

Operating rule

Part 121: Air Carrier

Purpose of flight

Unknown

Phase of flight

Not recorded

Route

Minneapolis → Chicago

Aircraft damage

Not recorded

Weather

VMC

Light

Night/Dark

NTSB number

CHI99LA184

1 person was seriously injured.

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.

Quoted verbatim from the NTSB record. This site does not paraphrase or interpret it.

Read the full NTSB narrative

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.

Quoted verbatim from the NTSB record.