What happened
On 6 September 1999, a Cessna 208B Caravan, registration LN-PBB, was conducting a scheduled cargo flight from Aberdeen to the Shetland Islands. After an initial diversion to Kirkwall due to poor weather at the primary destination, the crew decided to proceed to Sumburgh Airport once conditions appeared to have improved.
During the final approach to Runway 27, the aircraft was flying at a high speed, with the crew estimating approximately 140 kt as they became visual with the runway. The aircraft touched down approximately halfway down the runway after a bounce. Despite the application of full braking, the aircraft failed to decelerate sufficiently. As the aircraft approached the end of the runway, the commander applied full power in an attempt to clear the concrete sea defences located just beyond the airfield. The aircraft veered left, exited the runway, crossed a public road, and ultimately came to a halt after impacting concrete blocks. There were no fatalities among the two crew members, though the aircraft sustained severe damage to the landing gear, propeller, and fuselage.
The investigation
The AAIB investigation examined the runway surface, radar data, and wreckage. Radar analysis confirmed the aircraft's groundspeed was approximately 170 kt from 2,000 feet until touchdown. While there was no evidence of aquaplaning on the runway, investigators found evidence of heavy braking on the right main landing gear. The wreckage examination showed the aircraft struck the sea defences at roughly 50 kt with the propeller in a positive pitch position and engines at high power.
Witness accounts and video footage indicated the aircraft was already on the ground with all three landing gears in contact with the runway at the threshold. The investigation also reviewed the weather conditions, noting that while visibility was relatively good, the cloud ceiling was low, and the crew's decision-making regarding the approach was scrutinized.