United Airlines wants employees to approve cutting labor costs by one and a-half billion dollars annually over the next six years as part of its restructuring plan.
The cutbacks would include pay reductions and the scrapping of recently negotiated raises.
United is the largest carrier at Denver International Airport.
The moves would provide the bulk of the two and a-half billion the struggling carrier has targeted in annual savings in order to ensure its recovery.
These are the first specifics of United's plan to transform itself into a smaller, more cost-efficient carrier. They come at the halfway point of its self-imposed 30-day deadline for reaching agreements with labor and other groups on far-reaching cutbacks.
United is trying to qualify for one-point-eight billion dollars in loan guarantees from the Air Transportation Stabilization Board.
The unions have not yet responded to United's proposals, which were given to them on Wednesday.