Incident: Summit DH8A at Thunder Bay on Sep 10th 2023

A Summit Air de Havilland Dash 8-100, registration C-GASB performing a flight from Lansdowne House,ON to Thunder Bay,ON (Canada), was descending towards Thunder Bay when the crew received a pitch trim error announciation, disconnected the autopilot and attempted to manually trim the aircraft, however, while trimming nose down the trim stopped about half way. The crew declared PAN PAN advising they still had elevator control and would be able to trim nose up. The aircraft landed safely in Thunder Bay.

The Canadian TSB reported that seals on panels 332AT and 334AT had deteriorated permitting water to ingress the trim actuators. The trim actuator was purged and lubricated and the seals were replaced.