Boeing 757-223 N660AM

Summary

On 10 July 1997 at about 21:41 local time, a Boeing 757-223 registered N660AM was involved in an incident near Dickinson, North Dakota, United States. 155 people were on board and 22 had minor injuries. The aircraft was slightly damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

10 July 1997 at 21:41

Classification

Incident

Location

Dickinson, North Dakota, United States

Coordinates

46.8809, -102.7799

Aircraft

Boeing 757-223

Registration

N660AM

Category

Airplane

Engines

2

Operator

Not recorded

Operating rule

Part 121: Air Carrier

Purpose of flight

Unknown

Phase of flight

Not recorded

Route

Seattle → New York

Aircraft damage

Minor

Weather

VMC

Light

Day

NTSB number

FTW97IA261

22 people had minor injuries.

an encounter with unforecast convection induced turbulence (CIT). Related factors were: the flight crew's improper evaluation of the weather, and an inaccurate preflight weather briefing by company weather personnel.

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

Read the full NTSB narrative

The airplane was in level cruise flight at FL370, flying in an area of widely scattered thunderstorm cells. The airborne weather radar was set to the 160 nm scale, and the tilt was approximately 1 to 2 degrees down. One cell was observed 20 nm to the left of the airplane towering above its altitude, a second cell was 40 nm to the right, and a third cell 'came up independently underneath' and in front of the airplane. The FASTEN SEATBELT sign was not illuminated, but earlier, the captain had delivered an address to the passengers advising them of the possibility of a bumpy ride ahead and to '...keep your seatbelts on while in your seats.' The flight encountered convection induced turbulence (CIT), which resulted in minor injuries to 20 passengers and 2 flight attendants. There were no injuries to the other 120 passengers and 5 crew members. Vertical acceleration was between +2.01 and -0.75 g's. American Airlines meteorologists prepared the flight plan and entered a turbulence index of '0' for that segment of flight (from Billings, Mt, to Dupree, SD), indicating smooth air on average for the segment. Convective activity had been forecast for the area.

Quoted verbatim from the NTSB record.