The Transportation Safety Board says it closed the investigation into a near miss between a Porter Airlines plane and a still unknown airborne object that occurred high over Lake Ontario last week.
On Nov. 14, a Porter Airlines Bombardier Q400 turboprop plane was flying at an altitude of more than 2,700 metres over Lake Ontario, 55 kilometres east of Toronto near the marine border between Canada and the United States, when pilots noticed an unknown object barreling towards them.
TSB investigators said the pilots had only a few seconds to avoid the object, which they described as being as much as three metres wide.
The Porter pilots put the plane in a steep dive in order to dodge the object. Two flight attendants onboard the flight suffered minor injuries as a result.
None of the 54 passengers aboard were hurt.
TSB officials told CTV News Toronto that the description of the object did not match any known commercial or consumer drones currently on the market.
The investigation can be reopened if more information comes to light, officials said.
Commercially available drones are typically not designed to reach an altitude of 2,700 metres without some form of modification.
In Canada, drones are prohibited from flying higher than 90 metres above the ground, without first obtaining a special permit from Transport Canada.