The union representing America's flight attendants is calling it a gut punch.

United Airlines said on Wednesday it is preparing to send out furlough notices to roughly 45 percent of its staff; that's some 36,000 U.S.-based employees who could be temporarily out of work beginning October 1st.

United, like other U.S. air carriers, agreed to not make any layoffs until then in exchange for receiving billions of dollars in federal assistance.

According to United, the total number of employees who will actually get furloughed depends on how many workers accept early buyout packages, voluntarily take time off, and more importantly - how many fliers return.

Right now the airline is burning through $40 million in cash every day and the skies have turned even more unfriendly as of late. States have slowed or pulled back on reopening plans and travel restrictions out of New York, New Jersey and Connecticut have resulted in a recent drop-off in ticket sales.

Travel stocks are one of the hardest hit sectors in 2020. Shares of United are down 63 percent since the start of the year.