After the war, in 1919 Lawson started a project to build America's first airline. He secured financial backing, and in five months he had built and demonstrated in flight his biplane airliner, the 18-passenger Lawson L-2. He demonstrated its capabilities in a 2000-mile multi-city tour from Milwaukee to Chicago-Toledo-Cleveland-Buffalo-Syracuse-New york City-Washington, D.C.-Collinsville-Dayton-Chicago and back to Milwaukee, creating a buzz of positive press. The publicity allowed him to secure an additional $1 million to build the 26-passenger Midnight Liner. The aircraft crashed on takeoff on its maiden flight. In late 1920, he secured government contracts for three airmail routes and to deliver 10 war planes, but owing to the fall 1920 recession, he could not secure the necessary $100,000 in cash reserves called for in the contracts and had to decline them. In 1926 he started his last airliner, the 56-seat, two-tier Lawson super airliner.