Occurrence
On a day in September 2014, a Jazz Aviation LP de Havilland DHC-8-102 (registration C-GJMI, serial number 077), operating as Jazz flight 7794 (JZA7794), departed from Runway 22 at Sault Ste. Marie Airport, Ontario, bound for Toronto/Lester B. Pearson International Airport, Ontario. While climbing through approximately 4000 feet above sea level, the flight crew received a traffic alert from the aircraft's traffic alert and collision avoidance system and visually acquired a small aircraft (registration C-FANU, serial number 0681) positioned 3 miles ahead and approximately 1000 feet above.
Evasive Action
In response to the alert, JZA7794 levelled off at 4500 feet above sea level. However, C-FANU initiated a rapid descending turn toward the Jazz aircraft. The Jazz flight crew took evasive action by banking the aircraft 30° to the left. At 1557 Eastern Daylight Time, C-FANU passed the starboard side of JZA7794, with a lateral separation of approximately 350 to 450 feet.
Investigation
The Transportation Safety Board of Canada investigated this occurrence as a Class 3 investigation, which focuses on a limited number of safety issues and may result in recommendations. The investigation analyzed the events but did not assign a probable cause in the source.