KLM Flight 607-E

KLM Flight 607-E, a Lockheed Super Constellation named Hugo de Groot and registered PH-LKM,[2] was an international scheduled flight that crashed 180 kilometres (110 mi) northwest of Shannon Airport, Ireland on 14 August 1958. All ninety-one passengers and eight crew died in the accident, including six members of the Egyptian fencing team (Osman Abdel Hafeez, Mohamed Ali Riad, Ahmed Sabry, et al.).[3] The "E" in the flight number stood for the designation of being an extra economy class flight to match the increased seasonal tourist demand.[4]

KLM Flight 607-E

The Hugo de Groot, the aircraft involved in the accident.
Accident
Date	14 August 1958
Summary	Undetermined
Site	Atlantic Ocean (110 mi due west of Galway, Ireland).[1]
Aircraft
Aircraft type	Lockheed L-1049H-01-06-162 Super Constellation
Aircraft name	Hugo de Groot
Operator	KLM
Registration	PH-LKM
Flight origin	Amsterdam
1st stopover	Shannon Airport, Ireland
Last stopover	Gander, Newfoundland
Destination	New York City
Occupants	99
Passengers	91
Crew	8
Fatalities	99
Survivors	0

Flight 607-E departed Shannon at 03:05 UTC on the second leg of a transatlantic trip from Amsterdam to New York City with intermediate stops in Shannon and Gander, Newfoundland. Radio contact with the aircraft was lost at approximately 03:40 UTC; a rescue operation was launched which found light debris on the surface of the ocean approximately 180 kilometres (110 mi) west of Shannon. The remains of thirty-four of those on board were also recovered.[1]

Due to the lack of evidence, Irish and Dutch investigators could not pinpoint a probable cause for the accident. They examined the possibility of a bomb, electrical failure, or pilot error, but believed that the most likely possibility was a catastrophic mechanical failure.[5] The investigating Board believed the most likely cause of the accident to be a malfunctioning over-speeding outboard propeller caused by metal particles obstructing oil feed line regulator valves.[5] The particles may have been formed by a gear that was damaged when the supercharger of the corresponding engine was accelerated (gear ratio shifted).[5] The malfunctions of the propeller pitch might have provoked a flight disturbance and as a consequence the propeller may have sheared off.[5]