Equipment failure forced aircraft to return: TSB
Feb. 28, 2013, Gatineau, Que. - The Transportation Safety Board of Canada (TSB) today released its final air investigation report (A11O0031) into the March 13 2011 return after take-off of a Sunwing Airlines flight at Toronto-Lester B. Pearson International Airport.
The Sunwing flight was bound for Cozumel, Mexico, with 189 passengers and a crew of seven. During the early morning take-off run, the aircraft's autothrottle disengaged because of the failure of the airspeed monitoring equipment. The pilot continued the take-off but encountered additional problems on the climb-out. The pilot then informed air traffic control that the aircraft would be returning to the airport. The aircraft returned and landed uneventfully. There were no injuries or damage to the aircraft.
The investigation determined that a failure in the pitot-static system, a system used to determine the aircraft's airspeed, resulted in inaccurate airspeed indications, stall warnings, and, for unknown reasons, misleading commands being displayed on the aircraft flight instruments. The investigation also found that the operator delayed reporting the incident to the TSB because it did not recognize this event as a reportable aviation occurrence. The delay meant that valuable information on the flight data recorder and the cockpit voice recorder was lost.
The faulty equipment was replaced and the aircraft was returned to service. Sunwing has updated its safety management system to include a review of TSB criteria for reportable accidents and incidents. This is intended to facilitate timely reporting of occurrences.