Prior to World War I, Chicagoan Edward Heath played an integral role in the growth of aviation, focusing his efforts on enabling many working people to fly, not just the elite. He produced the Parasol, one of the most popular planes of its time, and his aircraft parts company quickly became the largest in the country. Heath developed the Kit Plane concept, allowing customers to purchase and assemble an entire plane, one affordable section at a time. Aviation historian Michael Haupt traces the path of the plane for the "ordinary pilot."