TSB investigators work to determine cause of plane crash west of Calgary

A federal body has taken over the investigation into a fatal plane crash near Springbank Airport Friday afternoon.

Workers with the Transportation Safety Board of Canada (TSB) were on scene Friday night and Saturday morning.

They were spotted poring over the debris that still lines farmland and a ditch along the Trans-Canada Highway.

Witnesses on that stretch of road Friday say they saw a plane heading north just after 3:30 p.m. They could see its altitude quickly dropping.

One driver tells CTV News the front of the small aircraft hit the top of a ditch just metres off the road before it flipped and came to rest facing south.

Bystanders were first on scene.

The witness says they were able to extinguish a small fire and pull out the plane's passenger.

"A 22-year-old female was transported by ground ambulance to a nearby hospital," RCMP Const. Lindsay Ralph said. "Officers attended the scene, along with emergency services and the fire department."

The woman is in life-threatening condition.

The pilot — a 45-year-old man — was pronounced dead on scene.

Their names have not yet been released.

According to the plane's tail identification, it's a 1981 Mooney M20K, which is a single-engine aircraft.

It appears to be privately owned.