WestJet Airlines Ltd. President and Chief Executive Officer Ed Sims is retiring from the company, less than a year and a half after sealing a deal to sell Canada's second-largest airline to private equity giants Onex Corp. for $5 billion.

WestJet said Sims would continue in his current role until the end of the year and will later take a senior advisory role with Onex Partners to help guide the its aerospace and aviation strategy, the company said in a release Wednesday. WestJet said its board will start looking for Sims' replacement as CEO.

WestJet Chair Chris Burley praised Sims’ role in guiding the airline through the worst year in commercial aviation history.

"Ed has led WestJet through the worst crisis in aviation history and will see us through to the end of 2021,” Burley said in a release. “We owe our relative strength and stability in no small measure to Ed's leadership and steady hand. On a personal note, we're pleased that Ed will be able to rejoin his family in New Zealand at the end of the year."

Globally, revenue passenger kilometers – a key airline traffic metric – plunged 65.9 per cent year-over-year in 2020 due to the pandemic, according to data compiled by the International Air Transport Association

Here at home, WestJet slashed domestic routes and suspended flights to sun destinations at the behest of the federal government. The airline has since restored domestic service to several Atlantic Canada destinations.

Sims joined the company in 2017 and was named President and CEO a year later when WestJet's former head Gregg Saretsky abruptly stepped down from his post. Prior to working at WestJet, Sims had a three-decade long career in the aviation, travel and tourism industry, including a stint as CEO of New Zealand’s air navigation service provider.