The WestJet Professional Pilots Association, which is pushing to unionize the company's roughly 1,300 pilots, says a Yes vote will create a legalized structure that will better address their concerns.
"The pilot group is concerned that the increasing burden placed on all employee groups in pursuit of corporate profits is damaging our product," wrote the group, which did not respond to a request for comment, on their website.
Ian Holloway, a labour expert and dean of the University of Calgary's law school, said that if WestJet employees opt to unionize, it could restrict how the airline operates.
"The attraction of having a non-unionized environment isn't typically the wage rates, but rather it's the flexibility," said Holloway.
Such flexibility was one of the key advantages WestJet had over Air Canada when it entered the market, but that nimbleness is eroding.
"WestJet is no longer the little guy," said Holloway.
"It's a huge pan-Canadian airline, and the growth and success has brought with it the same attended challenges that any other big airline has."
WestJet has been expanding from its Calgary headquarters in recent years, opening bases of operation in Toronto and Vancouver. The company also launched its first trans-Atlantic flights last year and is expanding those offerings this year.
But the pilots association says it has "serious concerns" that the level of representation has not kept pace with the immense changes that have taken place at the airline.
WestJet declined to comment on the vote, but the airline lauded the fact that its employees weren't unionized in its 2014 annual report.
"We have a non-union workforce that we believe gives us a competitive advantage and helps foster our unique corporate culture," the company wrote.
The company also expressed concern in the report that collective bargaining could lead to service disruptions, increased labour costs and a change in company culture.
"Unionization could also fundamentally change the dynamic of our relationship with our employees and may diminish our employee-friendly corporate culture and reputation, which could ultimately have a negative impact on our earnings."
David Tyerman, an analyst at Canaccord Genuity, said he isn't overly concerned about the notion of unionization on the company's stock.
"They have tried to unionize before, and nothing has happened, and it's completely possible that's what will happen again this time," said Tyerman.
But he added that while successful unionization would introduce a level of risk for the company, he didn't anticipate major changes, especially on the compensation front since WestJet employees are already fairly well-paid.
The WestJet Professional Flight Attendants Association is also pushing to have the airline's approximately 2,700 flight attendants unionize, but they are still working to have a majority of members sign up so they can cast their votes.
The confidential WestJet pilot vote runs between July 22 to Aug 5.
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