20th of April 1983
Updated: Apr 20, 2022
A de Havilland Canada DH-6 Twin otter 310 was operating a charter flight between Aberdeen (Scotland) and Flotta Airport on the isle of Orkney on this day in aviation history in 1983. Onboard a crew of two pilots and 10 passengers.
The aircraft wreckage shortly after the accident (Source: Orkney Image Library © Roy Davidson)
The aircraft took off from Aberdeen Airport at 11.18 local time, with sufficient fuel for the flight to Flotta Airport and back, as no refueling facilities were available. The weather that day was good, although a strong Westerly wind was present along the whole route.
At 11.56 lt the crew received a wind report, stating the surface wind to be 260º at 26 knots. With the runway at Flotta being 35/17 this meant a 90º crosswind whichever runway they would land on. The captain elected to land on runway 35, which meant a 90º crosswind from the left, this had his preference as he could "see" the left wheel onto the runway.
At 11.58 the aircraft reported being at long finals to 35 at Flotta, with the aircraft on a stable approach.
During the latter stages of the approach the crew received the following wind updates;
260º / 21 knots
260º / 28 knots
260º / 26 knots
260º / 24 knots
With the last one being the wind just before touchdown. The crew later did not recall receiving wind reports with wind strengths above 26 knots. The captain used the 'Wing Down' crosswind technique, and full flaps were selected at 200 feet as per procedure. The aircraft responded normally to control inputs, there were no handling problems. The aircraft crossed the threshold left wing down and with right rudder to keep the aircraft aligned with the aircraft centerline.
The aircraft touched down on the left main gear first, followed by the right main gear. When the nose gear touched down reverser thrust was selected and both the propellors went into reverse thrust pitch. Right at that time, the left wing started to lift, which was immediately countered by the captain by full left aileron and full left rudder. As this did not have the desired effect, the right-hand propellor was put back in forward thrust and engine power was increased.
This was insufficient to stop the right-hand wing tip from striking the runway, causing the aircraft to yaw to the right It then settled for a very short time on both mainwheels, after which it cartwheeled off the runway. it finally came to a stop on its left side, with both wings ripped off.
The aircraft wreckage after salvage (Source www.baaa-acro.com)
The crew freed themselves from the cockpit and went back into the cabin to assist the passengers to escape via the righthand emergency exit. None of the occupants was hurt in the accident. Firefighters applied foam to (remnants of) the left engine a sit was emitting smoke. There was no post-accident fire. The accident was investigated by the Air Accident Investigation Branch of the United Kingdom, they concluded their report (Available by clicking here) with the following probable cause and contributory factor;
"The accident was caused by a loss of control, shortly after touchdown, following a strong lateral gust which was in excess of the maximum cross-wind capability of the aircraft. The lack of accurate surface wind information at the runway threshold was a contributory factor."