Compass Airlines, a Minneapolis-based regional carrier that flew Embraer E175 jets for Delta and American Airlines, is closing its base at Seattle-Tacoma International Airport and laying off 197 people effective May 1.

The company disclosed the layoffs Friday in a 60-day WARN notice filed with the state Employment Security Department.

Compass, which leases the aircraft and operates them on behalf of the network carriers, lost its contract with Delta last August. As its Delta operation winds down over a period of 11 months, Compass’s fleet is shrinking from 56 to just 20 jets.

Compass’s space at Sea-Tac airport was part of that leased by Delta. Delta is replacing the work done by Compass by giving some of it to another regional partner, SkyWest, and by upgrading some other flights to mainline Delta jets.