63 Years ago today: On 13 February 1955 a Sabena Douglas DC-6 flew into a hill on a flight to Rome, Italy, killing all 29 occupants.

Date:Sunday 13 February 1955
Time:18:53 UTC
Type: Douglas DC-6
Operator:Sabena
Registration:OO-SDB
C/n / msn:43063/60
First flight:1947
Crew:Fatalities: 8 / Occupants: 8
Passengers:Fatalities: 21 / Occupants: 21
Total:Fatalities: 29 / Occupants: 29
Airplane damage:Destroyed
Airplane fate:Written off (damaged beyond repair)
Location:Monte Terminillo (   Italy)
Crash site elevation:1700 m (5577 feet) amsl
Phase:En route (ENR)
Nature:International Scheduled Passenger
Departure airport:Brussel-Haren Airport, Belgium
Destination airport:Roma-Ciampino Airport (CIA/LIRA), Italy

Narrative:
The Sabena DC-6 departed Brussels (BRU), Belgium at 16:17 GMT on a scheduled flight to Rome (CIA), Italy.
Contact with Ciampino ACC was initiated according to plan at 18:29 GMT, at which time the aircraft had passed over Florence at 17500 feet. At 18:48 Ciampino control asked the aircraft whether it had passed over Viterbo. Instead of answering this question directly, the crew inquired whether the Viterbo NDB was on full power. The controller replied that another aircraft had overflown the Viterbo NDB shortly before and had found it to be operating properly.
At 18:51 GMT the aircraft stated that it had passed over Viterbo NDB one minute previously and requested clearance to descend to 5500 feet ; this was granted . One minute later it inquired whether the Ciampino ILS were operating and received an affirmative reply. At 18:53, OO-SDB called Rome control but communication was suddenly cut off.
The airplane hit the slope of the Costone dell’Acquasanta at a height of 1700 metres.

Probable Cause:

PROBABLE CAUSE: “The navigation was conducted without making use of all such radio aids as would have permitted checking, and consequently correcting the drift of the aircraft whereas the crew actually remained unaware of the drift. In fact, instead of making sure they were over the Viterbo beacon, they merely held that conviction, and therefore the approach procedure to the Rome terminal area (which prescribes overflight of the Viterbo beacon) was erroneously applied. The following contributing causes may be taken into consideration, 1) crosswind to the route stronger than forecast; 2) weather conditions particularly unfavourable to radio reception in MF.”