Annoyed by a fuel stop on your direct flight? Why airlines can't always plan ahead

Travel delays. We've all been there.

But there's something about fuel stops that particularly irritates travellers. Why didn't the airline plan ahead? How could it not know the aircraft would need more fuel?

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In November Chad Hinchey was on a direct WestJet flight from Edmonton to Yellowknife when he says the pilot announced they were going to have to divert to Fort McMurray, Alta., because of bad weather.

Passengers were told that the plane didn't have enough fuel to attempt a landing in Yellowknife and fly to an alternate airport if it had to.

"Why would we leave Edmonton with not enough fuel?" Hinchey says.

The flight had been scheduled to land in Yellowknife at 11:30 p.m., and Hinchey was already watching the clock the 25-year-old had to be at work early the next morning.

"They had to be able to tell that the weather wouldn't have been great, if that was the case. Why was the plane not prepared for that outcome?"

Hinchey said the aircraft refueled in Fort McMurray and got into Yellowknifeafter 2 a.m.

"It doesn't make much sense. I understand that flight delays happen because of weather but there's no way you shouldn't be prepared."

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Weather, winds, and more

Laval St. Germain, a pilot for Canadian North, says most of the time airlines can plan ahead, but there are a whole host of factors that come into play, including weather, strong headwinds, slippery runways and technical issues.

Weather can also change quickly: a Canadian North flight could land with no issues, while an Air Canada flight just 10 minutes behind it could suddenly be up against 200 km/h winds and be forced to turn around and refuel.

"The weather can be absolutely perfect in Yellowknife but we still have to have enough fuel to go somewhere else. That's just the law," St. Germain said.

He said diversions are more frequent in the North because if the plane runs into trouble, there aren't as manyalternate airports.

"If you're flying in southern Canada, we have airports all over the place," he said.

Using Calgary as an example, St. Germain said a flight would have airports in Red Deer, Edmonton, Cranbrook, Lethbridge and Saskatoon as alternates. But that's not the case when flying into Yellowknife.

"It is always legit," said St. Germain. "I've been an airline pilot since 1990. I have never seen a flight cancelled because of not enough passengers on it.

"I've never seen a flight divert to get fuel just because we were too lazy to put enough fuel on. It's only because of safety and regulations that we ever do it."

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Jazz diverted 'couple times' in January

For its part, WestJet said it only had one flight bound for Yellowknife diverted to Fort McMurray last year, and it was in November. A spokesperson blamed the stop on weather.

Another spokesperson for Jazz Aviation, which operates flights for Air Canada Express, said the airline has already had "a couple occasions this month" when it was necessary to make an unscheduled fuel stop between Calgary and Yellowknife.

Debra Williams said the airline also made one stop in December, noting that "weather, winds and passenger load/baggage etc." are all factors in the decision to divert a flight.

Jazz declined to do an interview on those factors, but in an email Williams said, "we want to carry all passengers and luggage and dependent on weather on a given day a fuel stop may be required."

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A spokesperson for Canadian North said it's not necessary for its 737 aircraft to divert on flights that are less than two hours, such as the Edmonton to Yellowknife route. First Air said the same.

"As far as we are concerned that is not something that we do or need to do," Dan Valin, manager of communications for First Air, wrote in an email.

Diversions are costly

From a passenger standpoint, St. Germain knows how "incredibly inconvenient and bothersome" these stops are for passengers, but he says it's better to arrive late and safely than cancelling the flight altogether, or bumping passengers or bags.

"There's no conspiracy up there. There's nothing nefarious going on. It's just simply the numbers and the fact that we have to arrive safely, and we have to arrive with a whole ton of buffers as well," he said.

He said diversions are quite costly for airlines. The delayed flight can set off a domino effect if the aircraft was scheduled for more flights. And if the delays are the airline's fault, it's on the hook for hotel and food vouchers for all those passengers who missed connections.

"That all costs money," St. Germain said.

"We burn more gas, we take more time, and very importantly it impacts all the other flights in the network on that day. So we do not like diverting."

St. Germain acknowledgesthat these hidden factors can be frustrating for passengers, but insists it's always necessary.

"It's gonna add some time to the flight, I know, but that's just the reality of aviation sometimes."