Provincial Airlines flight SPR961, a DHC-6-300 Twin Otter (C-FWLG), and Air Labrador flight LAL205. a DHC-6-300 Twin Otter (C-FGON). suffered a mida-r collision while manoeuvring for final approach to runway 30 at the Natuashish Airport, Newfoundland and Labrador. Neither flight crew was aware of the other aircraft. The Provincial Airlines flight crew realized that a mid-air collision had occurred; the Air Labrador flight crew did not. The right aileron of the Provincial Airlines aircraft sustained substantial damage and the left horizontal stablizer of the Air Labrador aircraft sustained minor damage. Both aircraft landed safely without further incident. There were no reported injuries. Both aircraft were being operated in accordance with visual flight rules. Findings as to Causes and Contributing Factors 1. Neither aircraft was aware of the other?s presence. 2. Engaged in non-essential communications and having not heard any other aircraft at the Natuashish Airport, the attention of both flight crews was focused on landing and not actively scanning to ensure collision avoidance. 3. Neither flight crew followed the standard left-hand traffic circuit, which placed LAL205 in a position that would have made it difficult for the crew to see or be seen by the crew of SPR961