1972 Il-14 crash near Tsrancha, Bulgaria

On 4 November 1972, an "Il-14P" aircraft was operating a scheduled domestic passenger flight from Burgas Airport, Burgas, to Sofia – Vrazhdebna Airport, Sofia, People's Republic of Bulgaria, operated by Balkan Bulgarian Airlines‎. Even before its take-off from Burgas, the crew received information that the weather in Sofia was bad and visibility was below minimums, so the commander decided on a possible intermediate landing at Plovdiv airport and, once the meteorological conditions improved, to take off again for Sofia. On board the machine were 31 passengers and 4 crew members.

More than half an hour after take-off from Burgas, the captain was again informed that the weather in the area over Sofia was too unfavourable for landing, and he then directed the machine towards Plovdiv airport. On its way the aircraft entered dense clouds, in which the crew was unable to establish its exact location, but it received clearance to land and began a visual approach without knowing on which side of the airport it was. Shortly afterwards the aircraft crashed into a hill in the Rhodopes, near Tsrancha, at an altitude of 960 m, killing all 35 people on board.

The investigation established the presence of alcohol in the blood of the commander and the flight engineer, as well as a violation on their part of the established procedures and rules on the mandatory slightly more than eight hours of sleep before a flight. Also strongly contributing to the crash was the fact that the duty controller at Plovdiv airport gave instructions to the crew without knowing the air situation, the altitude of the aircraft and from where the pilots were making the approach.