Delta Air Lines flight attendants seeking to organize a union plan to rally at Hartsfield-Jackson International Airport on Thursday.

The Association of Flight Attendants has spent decades trying to unionize Delta flight attendants. While other major airlines are heavily unionized, Atlanta-based Delta is mostly non-union. Delta’s main unionized employee group is its pilots, represented by the Air Line Pilots Association.

Organizers say the Delta flight attendants will be joined at the rally by Delta ground workers and mechanics who are also seeking to unionize, under the International Association of Machinists and International Brotherhood of Teamsters. Union organizers will also circulate a mobile billboard displaying pro-union messages on a truck.

Rasaq Adeyemi, a member of the Delta AFA organizing committee, called the rally on Thursday the group’s largest day of action and said in a written statement that there is “nationwide momentum for organizing across sectors.”

Delta management said it expects no operational impact from the activity, as it expects that any of its employees who participate would be off-duty.

Delta has fought unionization efforts among its flight attendants, ground workers and mechanics.

“At Delta, we support our employees’ right to choose whether or not a union is right for them,” Delta said in a written statement. “We believe our direct relationship with employees is stronger, faster and more effective in driving improvements, which is why Delta employees have repeatedly rejected union representation over the past 20 years.”

In 2019, Delta came under fire for an anti-union flyer that encouraged workers to spend their money on a new video game system instead of union dues. The IAM filed election interference charges with the National Mediation Board, which declined to investigate the allegations.

A shareholder proposal is set for a vote at Delta’s annual meeting next month that, if approved, calls for a non-interference policy to uphold rights at Delta to collective bargaining, as union organizing efforts are underway. Delta management is against the measure.

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