Forty one aircraft, three Canadian airlines and almost six months out of service. The grounding of the Boeing 737 Max 8 is affecting Canadian flights from coast to coast, and for Westjet passengers it's now clear that impact will continue through the busy end-of-year holiday season.

Transport Canada has not yet given the jets permission to fly, but even if it does so before the end of the year, CBC News has learned Westjet will not be including the Max 8 jets in its holiday-season schedule, one of the peak travel times of the year.

Air Canada and Sunwing had already announced they won't be flying their Max 8s until next year.

It's possible the Boeing jets may be recertified to fly before the end of 2019 — Transport Canada isn't saying when that might happen. But Brian Znotins, Westjet's vice-president in charge of scheduling at the company's headquarters in Calgary, says his airline made the decision because it needed to give passengers some certainty in making holiday bookings.

If the Max 8 is allowed to fly in December, at most Znotins says the airline might consider an occasional flight to ease demand.

"It's a little harder to unmix the cake at that point, but we would look at peak days, the Friday before Christmas [for example] where we can still sell seats and we'll put the airplane back in."

No-fly decision

Until now, very little has been heard from Canadian airlines about the ongoing impact of the Max 8's problems. But Westjet agreed to talk to CBC's The National about the effects of the grounding on the airline's operations.

The issue with the Max 8 began with two disasters: A total of 346 people killed in crashes involving Indonesia's Lion Air in October 2018 and Ethiopian Airlines in March of this year.

A Lion Air Boeing 737 Max 8, parked on the tarmac of Soekarno Hatta International airport near Jakarta, Indonesia. All Max 8 jets, about 350 in service around the world, have been grounded since March this year. (Willy Kurniawan/Reuters)

Investigators were troubled by the similarity between the crashes. Pilots on both planes appeared to be struggling to maintain control of their aircraft when they went down.

Boeing has acknowledged the Maneuvering Characteristics Augmentation System (MCAS), designed to activate automatically to help keep a plane stable, seemed to be a factor in each crash. It appears erroneous air speed data triggered MCAS, which tried to push the nose of the jet down to increase speed while the pilots fought to counteract it.

In the days after the first crash on Oct. 29, 2018, some U.S. pilots complained Boeing hadn't revealed that MCAS was embedded in the Max 8's software. Speaking publicly for the first time on this issue, Westjet's vice-president of flight operations, Scott Wilson, told CBC News that Westjet shared that concern.

"Our job as pilots is to know and understand the aircraft so that we can apply that knowledge in a normal and not normal situation," he says. Not being told about MCAS, "created a bit of a trust deficit. There's no doubt about it."

Wilson adds that he made that erosion of trust clear to Boeing. "Absolutely. And they are well aware they've got to basically rebuild that gap."

After the Lion Air disaster, he says the three Canadian airlines that fly the Max 8 worked with Boeing and Transport Canada to review pilot training and procedures, what Wilson called "a made-in-Canada solution." He adds that the airlines were confident its pilots could fly the jet safely as a result.

But then on March 10 came the second catastrophic crash, Ethiopian Airlines Flight 302. Within hours, Wilson says Transport Canada was again in contact with Air Canada, Sunwing and Westjet, sharing information about the tragedy and assessing the safety of the jets.

An emergency crew works at the scene of the Ethiopian Airlines Max 8 crash near Bishoftu, south of Addis Ababa, on March 11. All 157 people aboard the aircraft were killed. (Mulugeta Ayene/Associated Press)

"Obviously we'd never move an aircraft ever without a 100-per-cent assurance of its safety … and the information that we had at the time led us to believe that at that moment, that there was no increased risk to operating the aircraft," Wilson says.

But governments around the world began taking action. The day after the Ethiopian crash, China banned the Max 8 from its airspace, and the next day the European aviation authority did the same. Three days after the crash, Canada and then the United States followed suit.

At the time, Canada's Minister of Transport Marc Garneau said there was new satellite data on the Ethiopian crash, "suggesting a possible although unproven similarity in the flight profile of the Lion Air aircraft."

Wilson explains that the data appeared to show that MCAS played a role in both the Lion Air and Ethiopian Airlines disasters. It wasn't conclusive, but it was enough to ban the Max from carrying passengers in Canadian airspace.

All Boeing 737 Max 8s — about 350 planes flown by more than 50 airlines around the world — have been grounded ever since, as the manufacturer works to fix the problem and prove to aviation officials that the aircraft is safe.

Scott Wilson, Westjet's vice-president of flight operations, in front of a grounded Boeing 737 Max 8 in the airline's Calgary hangar. He says issues around software in the jet have created 'a trust deficit' between pilots and Boeing. (Mia Sheldon/CBC)

Challenging logistics

For Westjet, the grounding has left 13 jets parked at airports from Vancouver to Toronto, about 10 per cent of the airline's seats. That has created an ongoing challenge for the airline's schedulers and maintenance team.

The person in charge of maintenance, John Kelly, says his airline's Max 8s are essentially ready to fly — their fluids are checked every 48 hours, and once a week each jet is powered up, taxis and then is parked again.

Westjet's vice-president of technical operations, John Kelly, takes CBC's Ian Hanomansing into the wheel well of a Boeing 737 MAX 8 to explain how the airline is keeping the aircraft flight-ready while they're grounded. 0:40

Standing in the gleaming Westjet hanger in Calgary, Kelly explained that the biggest challenge in this grounding hasn't been the maintenance involved in keeping the Max 8s on standby, but the need to get more hours from the rest of the airline's fleet.

"We pulled some planes out of heavy maintenance to help fly the schedule. We're doing a lot more work on the other airplanes to keep them healthy and keep them flying."

Among the work that's been deferred is the job of putting new seats in Premium class of the airline's older 737s, for example.

Mechanics do maintenance work on a Boeing 737 Max 8 in Westjet's hangar in Calgary. (Mia Sheldon/CBC)

Making planes available is just the first part of the puzzle. Then comes reworking the flight schedule.

If you want a sense of the complexity of running an airline, walk through its operations centre. For Westjet it's a room about the size of a gymnasium, filled with people tracking planes, watching the weather and calculating flight plans. When CBC News visited the centre, one of the scheduling issues the team was dealing with was fog in Prince George that had led to a two hour delay, which in turn affected that plane's upcoming Vancouver-Victoria-Vancouver trip.

Weather problems are a fact of life for airlines. The impact of removing 13 jets for an indefinite period is infinitely more complicated.

That's been the responsibility of Brian Znotins. With the uncertainty over when the jets will be returned to service, he has revised the airline's flight schedule five times.

He compares the process to building a house. "You take away 7 per cent of the bricks and you still want to build that house and you have to get pretty creative."

Brian Znotins oversees long-term scheduling for Westjet. He says uncertainty around when the 737 Max 8 will be able to return to passenger service has required the airline to revamp its schedules a number of times in recent weeks. (Mia Sheldon/CBC)

In a July 29 interview, WestJet chief executive Ed Sims told CBC News that the grounding of the Boeing 737 Max 8 is having a "substantial negative impact" on the airline. He declined to give specifics on the financial hit, but said the grounding has forced WestJet to increase spending on fuel and cut routes.

One summer route — Halifax to Paris — was cancelled for the season, for example. A direct flight from Vancouver to Regina has also been suspended. Some daytime flights have been moved to overnight. But with its older 737s flying more often, Znotins says Westjet has been able to maintain 98 per cent of what would have been its schedule with the Max 8s in the air.

It's a similar story at Air Canada. The bigger airline had a fleet of 24 Max 8s, and was expecting 12 more by the end of June. Asked about the impact of the grounding on its operations, Air Canada directed CBC to its most recent quarterly report, which states the airline has managed to cover "97 per cent of our planned flying" without those aircraft.

Aviation analyst Rick Ericksen says he's impressed with how Canadian airlines are coping and how all three have handled the grounding. But he says that aside from the lost revenue, the airlines have very little excess aircraft capacity left at the moment to deal with any other problems that may arise.

Awaiting clearance

The question remains: when will the Max 8 be cleared to fly again ?

All Transport Canada will say is that it "will not lift the current flight restriction … until it is fully satisfied that all concerns have been addressed by the manufacturer and U.S. Federal Aviation Administration, and adequate flight crew procedures and training are in place."

Air Canada has announced it won't fly the Max 8 any sooner than Jan. 8, 2020.

For Sunwing, it's May.

Westjet may be the best positioned of the three Canadian airlines to get the Max 8s up quickly once the flight restriction is lifted. Its Max pilots have been active, flying the airline's older-model 737s. Kelly, in charge of maintenance, says after a software update the Max 8s should be ready to fly.

But vice-president of flight operations Scott Wilson concedes there is another challenge the airlines will face: attracting passengers who may be reluctant to fly on a plane that's suffered two recent crashes.

Watch The National's story about how the Boeing 737 Max 8 grounding is affecting operations at Westjet: