It's the sound of the city this weekend: the roar of planes overhead as the Canadian International Air Show features vintage and modern planes in aerial displays. It's been running since 1949, and draws thousands of people to the waterfront.

Some people love the spectacle; others hate the disruption, or object to the military display.

But for some in the city it can also have an unsettling, perhaps even traumatic, effect.

Maya Bastian is a writer and filmmaker with family roots in Sri Lanka. In 2009, as the war in that country was ending, she went there to work in conflict zones. "I had never seen anything like it," she told CBC Metro Morning's Matt Galloway.

Bastian returned at the end of the summer, shortly before that year's air show. Standing out on the street, "any time a plane flew over I was paralyzed, I couldn't move ... I was reliving a lot of the things that I saw and experienced and heard in that moment."

The Breitling Aerobatic Team perform during last year's Canadian International Air Show. (Louis Nastro/Reuters)

Bastian is now working on a film based on the air show and people's reactions to it. One of her biggest concerns is the impact it has on Torontonians who've experienced actual aerial attacks, as opposed to the orchestrated showcase on display this weekend.

"No one — especially the immigrants and refugees that show up new to the city — they're not made aware of what's going to happen," Bastian says."No one tells them, 'Hey, there will be planes — warplanes — over the city. It'll be loud, it'll be disturbing.' So they're caught completely off-guard."

That isn't to say that Bastian is convinced the air show needs to end. But she does think there's a tension "between accepting refugees into our society and this sort of affront to their experiences."

It's an event whose purpose was very clear when it began, she adds. The question is whether that is still the case.

"It's part of the Canadian fabric ... In the '40s it was necessary; we needed it. Now I don't know that it is ... It's a complex question, and I'm not advocating to shut down the air show. What I'm looking for is discourse."