Midwest Airlines pilots spent much of Wednesday protesting what they call unfair treatment in front of U.S. Bank, Northwestern Mutual, and MillerCoors, three of their employer's largest clients.

The pilots' union has decried the airline's decision to replace Boeing planes flown by Midwest pilots with Brazilian regional jets flown by outside pilots.

"Northwestern Mutual as well as U.S. Bank and MillerCoors and many other organizations here in the Milwaukee area have been instrumental in the success of this airline over the years," said Midwest pilot Jake Southern. "We hope they realize and can help support our cause to try and continue the best care in the air."

The union has been meeting with Midwest management to discuss the possibility of Midwest union pilots flying Brazilian regional aircraft.