Massachusetts-based Cape Air (9K) operates regional flights in the Northeastern United States, Midwest, Montana, the Caribbean and Micronesia. The airline's hubs include Barnstable Municipal Airport (HYA), Luis Muñoz Marín International Airport (SJU), Boston Logan International Airport (BOS), Lambert-St. Louis International Airport (STL), Billings Logan International Airport (BIL) and Nantucket Memorial Airport (ACK). Flights between Nantucket and Barnstable Airports operate under the Nantucket Airlines brand. Flights in Micronesia, where the airline has a hub at Antonio B. Won Pat International Airport (GUM), operate under the United Express Brand. The airline has 89 planes and flies to a total of 36 destinations.