Date & Time: Dec 9, 1993 at 1839 LT
Operator:
Registration:
6V-ADE
Survivors:
No
Schedule:
Saint-Louis - Dakar
MSN:
393
YOM:
1973
Country:
Senegal
Region:
Africa
Crew on board:
2
Crew fatalities:
2
Pax on board:
1
Pax fatalities:
1
Other fatalities:
0
Total fatalities:
3
Circumstances:
Following an uneventful flight from Saint Louis, the crew was cleared to descend to Dakar-Yoff Airport and was instructed to maintain 3,000 feet over YF VOR. At the same time, a NAMC YS-11A-117 operated by Gambia Airways departed Dakar-Yoff Airport on a regular schedule flight to Banjul. Registered C5-GAA, the aircraft was carrying 34 passengers and a crew of four. Its pilots were instructed to climb via radial 140 and maintain the altitude of 2,000 feet while over YF VOR. When both aircraft reached the YF VOR, they collided. While the crew of the NAMC was able to return to Dakar and land safely despite the left wing was partially torn off, the Twin Otter entered an uncontrolled descent and crashed in the sea few km offshore. All three occupants were killed.
Probable cause:
It was determined that both crew failed to respect their assigned altitude, causing both aircraft to collide. At the time of the accident, the Twin Otter was about 100-300 feet too low and the NAMC was about 700-900 feet too high.