Narrative:
Northwest Orient Airlines Flight 710, was a scheduled service from Minneapolis (MSP) to Chicago (MDW) and Miami (MIA).
The Lockheed L-188C Electra departed Minneapolis at 12:51 and arrived at Chicago-Midway Airport at 13:55. During the short time the aircraft was on the ground at Chicago, approximately 30 minutes, it was refueled and prepared for continuation of the flight to Miami. The flight took off from Midway Airport at 14:38.
At 15:13, Flight 710 reported over Scotland, Indiana, maintaining 18000 feet and estimating Bowling Green, Kentucky, at 15:35. This was the last radio contact with the flight.
At 15:25 the outboard engines and engine support structures, the complete right wing, and the outer portions of the left wing and ailerons separated in flight. The aircraft crashed out of control.
PROBABLE CAUSE: "The Board determines that the probable cause of this accident was the separation of the right wing in flight due to flutter induced by oscillations of the outboard nacelles. Contributing factors were a reduced stiffness of the structure and the entry of the aircraft into an area of severe clear air turbulence. "
Wing failure
Loss of control
accident date: 17-03-1960
type: Lockheed L-188C Electra
registration: N121US
accident date: 17-03-1960
type: Lockheed L-188C Electra
registration: N121US
accident date: 17-03-1960
type: Lockheed L-188C Electra
registration: N121US
accident date: 17-03-1960
type: Lockheed L-188C Electra
registration: N121US
| Status: | Accident investigation report completed and information captured |
| Date: | Thursday 17 March 1960 |
| Time: | 15:25 |
| Type: |  Lockheed L-188C Electra |
| Operator: | Northwest Orient Airlines |
| Registration: | N121US |
| MSN: | 1057 |
| First flight: | 1959-07-01 (9 months) |
| Total airframe hrs: | 1786 |
| Engines: | 4 Allison 501-D13 |
| Crew: | Fatalities: 6 / Occupants: 6 |
| Passengers: | Fatalities: 57 / Occupants: 57 |
| Total: | Fatalities: 63 / Occupants: 63 |
| Aircraft damage: | Destroyed |
| Aircraft fate: | Written off (damaged beyond repair) |
| Location: | 9 km (5.6 mls) NE of Cannelton, IN ( United States of America)
|
| Phase: | En route (ENR) |
| Nature: | Domestic Scheduled Passenger |
| Departure airport: | Chicago-Midway Airport, IL (MDW/KMDW), United States of America |
| Miami International Airport, FL (MIA/KMIA), United States of America | |
| Flightnumber: | 710 |
Northwest Orient Airlines Flight 710, was a scheduled service from Minneapolis (MSP) to Chicago (MDW) and Miami (MIA).
The Lockheed L-188C Electra departed Minneapolis at 12:51 and arrived at Chicago-Midway Airport at 13:55. During the short time the aircraft was on the ground at Chicago, approximately 30 minutes, it was refueled and prepared for continuation of the flight to Miami. The flight took off from Midway Airport at 14:38.
At 15:13, Flight 710 reported over Scotland, Indiana, maintaining 18000 feet and estimating Bowling Green, Kentucky, at 15:35. This was the last radio contact with the flight.
At 15:25 the outboard engines and engine support structures, the complete right wing, and the outer portions of the left wing and ailerons separated in flight. The aircraft crashed out of control.
Probable Cause:
PROBABLE CAUSE: "The Board determines that the probable cause of this accident was the separation of the right wing in flight due to flutter induced by oscillations of the outboard nacelles. Contributing factors were a reduced stiffness of the structure and the entry of the aircraft into an area of severe clear air turbulence. "
Accident investigation:
 |
|
Classification:
TurbulenceWing failure
Loss of control
Follow-up / safety actions
The FAA requested Lockheed to conduct an engineering reevaluation of Electra model airplanes following two fatal accidents (Sept. 1959 and March 1960).
The program disclosed two discrepancies in the design of the airplane. One, significant loads imposed on the wing's intermediate ribs between the fuselage and outboard nacelles by shell distortion had not been included in the design loads. Two, the dynamic response of the outboard nacelles in turbulence was different from the design assumptions.
Lockheed redesigned the engine mounts, nacelles, and cowlings, and modified the wing to improve strength capabilities. No Electra accidents have resulted from whirl-mode flutter since. FAA issued 2 Emergency Airworthiness Directives
Show all...
The program disclosed two discrepancies in the design of the airplane. One, significant loads imposed on the wing's intermediate ribs between the fuselage and outboard nacelles by shell distortion had not been included in the design loads. Two, the dynamic response of the outboard nacelles in turbulence was different from the design assumptions.
Lockheed redesigned the engine mounts, nacelles, and cowlings, and modified the wing to improve strength capabilities. No Electra accidents have resulted from whirl-mode flutter since. FAA issued 2 Emergency Airworthiness Directives
Show all...
Photos
accident date: 17-03-1960
type: Lockheed L-188C Electra
registration: N121US
accident date: 17-03-1960
type: Lockheed L-188C Electra
registration: N121US
accident date: 17-03-1960
type: Lockheed L-188C Electra
registration: N121US
accident date: 17-03-1960
type: Lockheed L-188C Electra
registration: N121US
Map
This map shows the airport of departure and the intended destination of the flight. The line between the airports does not display the exact flight path.
Distance from Chicago-Midway Airport, IL to Miami International Airport, FL as the crow flies is 1892 km (1183 miles).
Accident location: Exact; as reported in the official accident report.
Distance from Chicago-Midway Airport, IL to Miami International Airport, FL as the crow flies is 1892 km (1183 miles).
Accident location: Exact; as reported in the official accident report.
This information is not presented as the Flight Safety Foundation or the Aviation Safety Network’s opinion as to the cause of the accident. It is preliminary and is based on the facts as they are known at this time.
languages: 
United States of America
Share
Lockheed L-188
- 222 built
- 3rd loss
- 3rd fatal accident
- 2nd worst accident (at the time)
- 8th worst accident (currently)
United States of America- 6th worst accident (at the time)
- 46th worst accident (currently)
The Aviation Safety Network is an exclusive service provided by:
