WASHINGTON, Aug 18 (Reuters) - The parent company of new low-cost U.S. air carrier Breeze Airways said on Wednesday it had closed a $200 million Series B funding round led by funds and accounts managed by BlackRock Inc(BLK.N) and Knighthead Capital Management LLC. Breeze Aviation Group Inc previously raised more than $100 million and began flights in late May. Breeze is now serving 16 U.S. cities and 39 routes. The company said it would use the funding to expand operations. Breeze Chief Executive David Neeleman said on Wednesday the carrier has had more than 100,000 passengers since launching operations. Breeze currently has 13 airplanes and is focusing on flights between smaller U.S. cities that have little or no direct service from larger carriers. Breeze is serving cities like Tampa, Florida; Charleston, South Carolina; New Orleans, Norfolk, Virginia, Louisville, Kentucky; Tulsa, Oklahoma, Hartford, Connecticut, and Akron, Ohio. Neeleman said in an interview the new funding showed the airline was "here to stay." He said the funding would allow the airline to "be opportunistic about some airplanes that might be available." He said the airline had to work to develop the new routes that are not served by other direct flights. "It"s just getting the word out," he said, adding Breeze was profitable on many routes on a variable cost basis. "We"re off to a good start." Breeze plans to begin taking delivery of 60 new Airbus (AIR.PA) A220 aircraft starting in October, which will be delivered at a rate of about one per month for the next five years. It plans to use the A220 aircraft on routes longer than two hours’ flight time. It is Neeleman"s fifth commercial airline startup, including JetBlue Airways Corp (JBLU.O) and Canada"s WestJet. He said Breeze is the "most capitalized startup in U.S. aviation history by far."