"Aviation in Southern Indiana entered a new era in the 1950s following the closure of Bush Field. This modern period, characterized by stability and manageable growth in the general aviation market, extends to the present day, the centennial of local aviation.

"The era began with the opening of Hap's Airport, a small but popular private airfield north of Clarksville, whose founding averted the demise of local general aviation. Flying in Southern Indiana became practically synonymous with the little airport and its legendary owner in the nearly thirty year run of the field. The era also included the renewal of efforts in the mid-1960s to create the area’s first public airfield. Leaders of this movement realized that future growth of local aviation depended on the financial support only possible through the public sector. Clark and Floyd County business and government leaders united to explore a joint airfield as they had in the postwar period, but parochial political concerns led to the counties splitting their efforts. Floyd’s individual effort soon unraveled, but Clark’s continued energetically. Having to proceed alone, however, contributed to a difficult, highly protracted effort requiring thirteen years of site determination, fundraising, and land acquisition that finally culminated with the construction of Clark County Airport and its official opening in late 1981. The story of local general aviation over the last twenty-five years thus corresponds with the growth taking place at that airport, now known as Clark Regional Airport, and its plans for the future.

"...William 'Hap' Happel—the third of Southern Indiana's three most influential aviation advocates—emerged as the leading figure in this modern period. Happel saved local general aviation after the turbulent postwar period and managed its gradual growth at his airport over three decades. The public officials guiding the creation of the area’s first public airport relied on Happel's experience as they planned for a new airport and they eventually chose him as the field's manager, a position he still retains some twenty-five years after the airport’s opening. Local general aviation has flourished under him and the others responsible for the creation and operation of Clark Regional Airport. This success was anything but certain in the early 1950s, however, when Happel struck out on his own."