A Beechcraft A100 King Air, operating Strait Air flight 107 suffered a runway excursion after landing at Havre-Saint-Pierre, Canada. The charter flight touched down at Sept-?les (CYZV) at 08:36 and took off again for the third flight leg at 1049, bound for Havre-Saint-Pierre (CYGV). The aircraft conducted an approach to runway 08, which was snow-covered, while visibility was reduced due to heavy snow showers, and landed approximately 3800 feet beyond the threshold, at approximately 700 feet from the end of the runway. It continued its landing roll beyond the runway until it came to rest in a snowbank, approximately 220 feet beyond the end of the runway. The aircraft sustained substantial damage. Four of the occupants received minor injuries. Findings as to causes and contributing factors – The captain continued the approach beyond the final approach fix when the reported visibility was below the approach ban minima. – During the approach, runway lighting was reduced to medium intensity, which was 30% of maximum strength, thereby reducing the probability of seeing the visual references required to conduct the landing on the runway. – The captain proceeded with the landing sequence, without seeing or knowing the length of the remaining runway ahead and unable to accurately assess the aircraft’s position. – The aircraft landed approximately 3800 feet past the threshold, 700 feet from the end of the runway, and stopped its landing roll in a snowbank, 220 feet beyond the runway. – The deviation from standard operating procedures at a critical moment of flight was a source of confusion between the flight crew members, to the point where the aircraft was not configured for a landing, which increased the landing distance required. – The captain, focused on the landing manoeuvre and experiencing narrowed attention, was unable to make the decision to conduct a go-around. He lost the notion of time and flew over the runway for 20 seconds, not realizing that it was now impossible to touch down and come to a stop before the end of the runway. – Without policies, clear procedures and training, the first officer did not have the tools necessary to shift from a passive advisory role to proactive assertiveness strong enough to convince the captain to conduct a go-around. – The approach ban was ineffective in preventing this approach while visibility on the ground was below the minimum required for an approach ban.