Just days before what was supposed to be his parents' 50th anniversary, Scott Dearman is mourning the loss of his mother and planning her funeral after she waited more than four hours for an air ambulance to transport her to an Ottawa hospital.

"I'm waiting to wake up from this nightmare," he said. "I can't believe my mom's gone."

Last Wednesday, the hospital in Barry's Bay where Judy Dearman, 69, was being treated asked Ornge to transport Dearman to Ottawa—about 150 kilometres away—for treatment.

The family was told that no air ambulance was available.

The hospital then arranged for a land ambulance for Dearman. Her husband, Clyde, went home to pick up an overnight bag before driving to Ottawa. When he got to the city he was told his wife Judy hadn't arrived. He then drove back to Barry's Bay.

An Ornge air ambulance finally arrived more than four hours later.

"My understanding is that at the point that mom made it to the hospital, it was too late for her," Scott Dearman said.

By the time his mother arrived in Ottawa, she was barely conscious and was experiencing liver failure.

"We don't know if those four hours may have given her a better chance or if it was already too late," Dearman said. "But it didn't help."

Judy Dearman died two days later.

Her case was the second time in less than a week Ornge had failed to respond on time to an emergency call.

On the same day Dearman was waiting for an air ambulance, the company also failed to respond to a fatal collision north of Toronto.

Ornge said it couldn't send a helicopter there because the morning crew—who had worked overtime the day before—wasn't available for another half-hour due to federal rules requiring time off.

The organization has been under fire for months over questionable business deals and sky-high executive salaries that were hidden from public view.

It is now under a criminal probe for "financial irregularities."

With a report from CTV Ottawa's Vanessa Lee