The chief executive officer of WestJet Airlines Ltd. (WJA.TO) says he’s confident in the still-grounded Boeing Co.’s (BA.N) 737 Max, but the Canadian air carrier won’t fly the jets until it’s fully confident in the aerospace giant’s safety procedures.

“I believe in the Max, I believe in the reliability of Boeing,” Ed Sims said in an interview with BNN Bloomberg’s Tara Weber.

“But before I can get onto that confident platform and look to start our ordering process again for the 45 [737] Max aircraft that we can see ourselves operating by the mid-2020s, we need to ensure that we have a very rigorous path of regulatory certification.

“We need to make sure that Boeing understands, as we understand, that no aircraft will go back into constrained airspace until we have 100 per cent confidence in the safety of the procedures that they will be rolling out.”

Boeing’s best-selling jetliner has been grounded by authorities across the globe since last spring after two crashes killed 346 people.

Sims said the grounding of WestJet’s 13 Boeing 737 Max 8s has affected the Calgary-based company’s business significantly, and the airline has held talks with Boeing about compensation for losses.

“It’s had a very significant impact. It’s taken eight to 10 per cent of our total capacity out, and so we’ve had to work that much harder, particularly to recover the fuel efficiency that the Max offers,” Sims said.

“We are at a well-developed stage of conversations about the costs that we’ve incurred during the course of the loss of this aircraft. And we’ve taken the view that clearly the ongoing losses will need to be reflected in the nature of those commercial discussions with Boeing.”

Earlier this month, WestJet’s low-cost subsidiary Swoop partly blamed a wave of flight cancellations on the Max aircraft’s grounding. Swoop said it had limited options to charter other aircraft for stranded passengers in light of the out-of-service Boeing jets.