Several hundred baggage handlers, wheelchair attendants, skycaps and cabin cleaners are planning to go on strike at Boston Logan International Airport.
The workers are employees of JetBlue subcontractors Flight Services & Systems and ReadyJet, and they are protesting alleged threats from management over the workers' attempts to unionize.
Officials say the strike will start at 4:30 p.m. Wednesday, with no end date set. At least 500 people are expected to participate.
Neither company has responded to requests for comment. JetBlue says it is preparing extra staffing and it expects minimal impact.
Many politicians have voiced their support for the strike, including Democratic Mayor Martin Walsh. He previously said unionization is a "right as American workers."
The Massachusetts Port Authority that operates the airport has declined to comment.