The United Master Executive Council of the Air Line Pilots Association (MEC), which represents more than 12,000 pilots at United Airlines, has announced a picket to take place next April 6 at the headquarters of PAR Capital and Altimeter in Boston, to protest the attempt of the hedge funds to gain control of the board of directors of the Chicago-based carrier.

In a letter from the MEC to its members, the union accuses the firms to “have made disturbing statements in an attempt to force many changes within United’s Board of Directors.”

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The hedge funds proposed a six-member shareholder slate, headed by former Continental CEO Gordon Bethune. Todd Insler, Chairman of the MEC, alleged that the proposal is “being done for their own benefit and without publicly stating their intentions for the future of the airline.”

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Munoz took over as United’s CEO in September, aiming to build morale after years of strained labor relations. He replaced Jeff Smisek, who resigned amid a Federal investigation probing the link of the Chicago-based carrier to the Port Authority of New York & New Jersey (PANYNJ), operators of Newark Liberty International Airport.

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ANALYSIS: Jeff Smisek is Out at United

“Thankfully, and due wholly to our past sacrifices, our situation has dramatically improved. Now is not the time for hedge fund minority shareholders to reward themselves at our expense. Now is the time for all stakeholders to benefit from continued reinvestment in our airline’s corporate infrastructure, customer experience, new aircraft, maintenance, training, IT, and improved contracts.“ The union said in the letter.