HAY RIVER - Passengers on a recent flight out of Yellowknife had a harrowing experience when their aircraft's right-side propeller stopped spinning several minutes after takeoff.

This First Air ATR 42 aircraft returned to Yellowknife Airport on Aug. 8 after experiencing low oil pressure in its right-side engine just after takeoff. - photo courtesy of Norma Harris

The First Air flight crew, who had shut the engine off because of low oil pressure, declared an emergency and returned to Yellowknife.

"We were kind of freaked out," said Norma Harris, one of the passengers on the Aug. 8 flight bound for Hay River. "It was scary just knowing that we were only flying on one engine. Thank God, it wasn't halfway through the flight that it had conked out or something."

Harris, who was flying home to Hay River, said all the passengers appeared worried, but there was no panic.

Five passengers and three crewmembers were aboard the ATR 42 aircraft.

"On the climb out, (the pilots) had an indication of a low oil pressure warning and so, as a precautionary measure, they shut the engine down and followed the standard operating procedures and declared an emergency, and returned to Yellowknife," said Chris Ferris, vice-president of marketing and sales at First Air headquarters in Kanata, Ont.

The aircraft was never in danger, according to Ferris, who explained the engine was shut off to prevent damage.

The First Air executive compared the incident to an oil light coming on in a car.

"You can continue to drive, but you may seize the engine," he said. "Obviously, the oil is key to the smooth operation of the engine. So as a precautionary measure and because they can fly on one engine, they shut down the engine and returned to a base where they can get it looked after."

Ferris said, because an emergency was declared, Transport Canada and the Transportation Safety Board of Canada were advised of the incident.

Under First Air's safety management system, it prepares what's called a Hazardous Occurrence Incident Report, he noted. "It gets fully investigated internally by us. I can't comment on what Transport Canada or the Transportation Safety Board will do. Sometimes they will just review our investigation."

Harris, 43, is concerned by the fact the airplane had taxied out onto the tarmac and returned to the terminal because of a mechanical problem before it took off for Hay River.

"About a half an hour later, we got back on the plane and we taxied out on the runway and we took off," she recalled, noting unusual noises could be heard and unusual vibrations could be felt in the aircraft not long after takeoff.

The passengers were then informed the plane would be returning to Yellowknife.

Harris wonders whether the plane took off with a mechanical problem.

However, Ferris said the mechanical issue which initially caused the plane to return to the terminal was not related to engine oil pressure.

"On the taxi out to the runway, they had a mechanical issue that came up on their checklist in the cockpit," he explained. "They tried to reset the system while they were taxiing out, but there was no change. So they returned back to the gate to get the maintenance on the ground to take a look at it. It's an unrelated issue completely to the engine shutdown and return, totally unrelated."

Ferris said there was no safety concern with taking off after the first issue – involving what's called a bleed air leak alert – had been dealt with.

"Our pilots definitely follow all the guidelines and procedures," he said. "If they had any question about safety, they'd refuse to take the aircraft."

Ferris said it would be an unusual experience for passengers aboard a plane to return to an airport.

"It can be an anxious moment or two for passengers," he said.

ATR 42 aircraft, which have a capacity of 40 passengers, have been part of First Air's fleet since 2001.

Ferris called it a very safe type of plane. "It's been a very good aircraft for us."