KLM Flight 607-E

KLM Flight 607- E ( Hugo de Groot ) was a flight of Dutch airline KLM with a Lockheed L- 1049H -01- 06-162 Super Constellation (air vehicle registration: PH -LKM ), which on August 14, 1958 west of the Shannon to the Atlantic crashed. In this case, all 99 occupants were killed. The Definitive cause of the accident could not be determined.

Construction and in- service position

The Hugo de Groot was a machine from the Model L - 1049H, the latest version of the L- 1049th These models were manufactured from 1957 and were intended for mixed passenger and freight transport. The Hugo de Groot had two large cargo doors on the port side of the fuselage. In addition, a reinforced heavy-duty floor was built as a so-called Scooter floor, which allowed the use of material handling equipment for transporting pallets.

The Hugo de Groot was built with the serial number 4841 1958 and received at the in- service position, the radio call sign PH -LKM. The aircraft was named by KLM after the Dutch theologian, philosopher and enlightener Hugo Grotius ( 1583-1645 ).

Crash

The KLM flight 607E was the second leg of a transatlantic flight from Amsterdam to New York City with stopovers in Shannon and Gander, Newfoundland. The plane took off as scheduled on August 14 in Shannon at 03:05 GMT to their Atlantic crossing to Gander. On board were 91 passengers, the pilot and copilot, and six other crew members. The last radio contact with the aircraft was at 03:40 UTC, so instead of 35 minutes after the start. After that there was no contact.

The crash probably happened about 180 km (110 miles) west of Shannon, Ireland, on the Atlantic Ocean. Wreckage were found in this area north-northwest before the Irish coast in the lake. The calculated position of the machine they situate further on the Atlantic, was therefore assumed that the pilot had tried after a technical problem turning around. The bodies of the 34 people were rescued. Due to the unknown depth of the crash site a salvage into consideration was drawn.

Background and cause

The investigation report of the Irish and Dutch investigators after the crash could find no clear cause of the crash. With a certain probability overspeeding was adopted by a propeller of one of the two outer engines by dirty motor oil. By possible metal particles could the control valves of the control of the constant- speed - pitch propeller, which is supplied by the engine lubrication system with hydraulic oil as the working medium, may have been affected, so that the angle of attack of the propeller blades of the engine concerned reduced invalid, on the other hand, the low-resistance feathering ( feathering ) the propeller could not be brought about. Due to the low angle of attack for the air speed to be formed in spite of increasing the maximum engine speed in comparison to the other three, correctly working engines no propulsive force and a braking torque. Therefore, when the situation of the crew is not immediately recognized and consistently opposed by counter-steering effect, enter through the driving forces asymmetrically distributed an uncontrollable flight condition that could have led to the crash. Hypotheses were that pilot error or a bomb explosion led to the crash, the report classified as an unproven hypothesis.

The Hamburg-based weekly news magazine Der Spiegel reported in August 1958 in detail about the crash of the Super Constellation and the belated search of the machine due to lack of radio communications. Disorders of the radio operation over the North Atlantic were in aviation at this time as commonplace. After the Hugo de Groot not as scheduled reported by radio, the air traffic control in Shannon limited, first, notify the shipping of the coast radio station " Valentia Radio" in Ireland, that the aircraft was no longer reported. Position information or a calculated price has not been mentioned, so that shipping could not do anything with this information. Der Spiegel wrote that the susceptibility of the radio communications between aircraft and ground station " paradoxically due to a technical innovation " was. Some airlines, including KLM had abolished the Morse code in accordance with the safety recommendations of the International Civil Aviation Organization ICAO in transatlantic traffic and only used a radio communications. The crashed over the North Atlantic KLM plane had therefore no full-time radio operator on board. The KLM Directorate had declared before the crash: " The radio has proven itself He makes the transmission of messages between the radio operator and the pilot, misunderstandings can easily occur when the superfluous, because the pilot receives or delivers all messages themselves. . "

Radio experts at that time did not exclude the possibility that perhaps some survivors could have been saved if an ordinary Morse instrument on board the Dutch machine would have been for emergencies. That a professional radio operator may be time had found to hammer a distress call in the Morse key, experts concluded, inter alia, from the evidence that was found by the rescue ships a child to whom a life vest was applied. With a sudden crash or an explosion would have been no time to do so.

In the machine there also six members of the Egyptian National team were in fencing. The "E" in the flight number was for economy class. The flight was also set up to meet the increased seasonal tourism demand.

Follow

After the accident, the inspection took good note that the propeller governor of the engines were ( Governor ) equipped with safety mechanisms to ensure that the adjustment mechanism reliably brings about the feathering of the propeller blades ( feathering ). Based on the results of the study suggested that the investigation report further to separate the pressure oil supply to the propeller governor from the engine lubrication to prevent malfunction of the propeller due to contamination in the oil.