58 Years ago today: On 11 June 1961 a KLM Douglas DC-7C suffered a violent engine vibration, followed by engine separation while in flight over the Atlantic Ocean; a safe emergency landing was made at Prestwick Airport, UK.

Date:Sunday 11 June 1961
Type: Douglas DC-7C
Operator:KLM Royal Dutch Airlines
Registration:PH-DSN
C/n / msn:45546/1031
First flight:1958
Total airframe hrs:9318
Crew:Fatalities: 0 / Occupants: 8
Passengers:Fatalities: 0 / Occupants: 73
Total:Fatalities: 0 / Occupants: 81
Aircraft damage:Substantial
Aircraft fate:Repaired
Location:over Atlantic Ocean (   Atlantic Ocean)
Phase:En route (ENR)
Nature:Int’l Non Scheduled Passenger
Departure airport:Windsor Locks-Bradley International Airport, CT (BDL/KBDL), United States of America
Destination airport:Glasgow-Prestwick Airport (PIK/EGPK), United Kingdom

Narrative:
DC-7 PH-DSN departed New York-Idlewild for Bradley Field where 73 passengers boarded the plane . At 22:26 the aircraft departed for Amsterdam with a planned intermediate stop at Prestwick. At 07:15 GMT, while cruising at FL170 over the Atlantic Ocean, heavy vibration occurred in the no. 1 engine and propeller. The aircraft lost speed and started to descend. The crew prepared for a ditching when suddenly at 07:30 the no. 1 engine broke loose and fell into the sea. The flight continued and landed safely at Prestwick around 08:45

Probable Cause:

PROBABLE CAUSE: “Failure of the forward propeller shaft bearing on No.1 engine. Violent vibration, which could not be stopped, arose in No.1 propeller and resulted in fire and separation of the entire No.1 power unit.”