Bangkok Airways Flight 125

Bangkok Airways Flight 125 was a scheduled domestic flight from Don Mueang International Airport to Koh Samui Airport. On 21 November 1990 the Dash 8-100 operating the flight crashed on approach to Koh Samui Airport during bad weather, 5 km southwest of the airport, killing all 33 passengers and 5 crew. Bangkok Airways Flight 125 was the first fatal accident of Bangkok Airways.

The subsequent investigation determined that the cause of the accident was the pilots suffering spatial disorientation that led to a loss of control.

Accident
Flight 125 departed Don Mueang International Airport at 09:58 UTC. The flight was conducted under IFR and proceeded to climb to a flight level of 210 (21,000 ft). At 10:45 as the aircraft approached Koh Samui Airport, the crew contacted the control tower and were informed that runway 17 was active. The tower also advised that the weather was mild with rain southeast of the airport. Due to changing wind conditions on the ground the crew was instructed to use runway 35. While attempting to line up for runway 35, errors caused the crew to perform a missed approach. The tower directed the aircraft to make left turn to avoid mountains and flight 125 started a left roll with flaps fully extended in heavy rain. The crew became disoriented and began descending while still in a left roll. The aircraft crashed into a coconut farm 5 km southwest of Koh Samui Airport, with the loss of all 33 passengers and 5 crew. Bangkok Airways Flight 125 was the first fatal accident of Bangkok Airways.

Aircraft
The aircraft was a two-year-old Dash 8-100, registered HS-SKI, msn 172. It was first flown in 1989. At the time of the accident, the aircraft had accumulated 3,416 flight hours and 2,998 take-off/landing cycles.