It’s considered one of Canada’s worst air disasters.

Back in 1963, Trans-Canada Air Lines Flight 831 caught fire and blew up shortly after takeoff from Montreal’s Dorval Airport.

A total of 118 perished.

Over 300 relatives marked the 50th anniversary Friday with a memorial service.

Today, they’ll visit the crash site, a field in Ste. Therese-de-Blainville or visit a local museum where there’s an exhibit recalling the crash, the cause of which was never determined.