International Intrigue, Paper Clips, and Envelope Pushing Research in the Heartland 2004-01-1800

The U.S. heartland city of Wichita has long been known initially, of course, as a cowtown but then as a hotbed of rock solid aviation, especially - but not solely - General Aviation. But few would associate it with either far out aeronautical research or, even less, international intrigue. Yet at just about the midpoint of the first century of flight it was the focal point for researchers from two sometime military adversaries of the U.S. to join with locals to perfect a system of lift enhancement that demonstrated performance measures never achieved before or, in practice, since. The routes that those foreign-born researchers took to get to Wichita provide a story as fascinating as the research itself. (Paper clips were an accommodating feature of relocation.) That their work would find application in some of the foremost American fighter planes of the Cold War era gives a bizarre ending to the episode, since the flying testbeds for evaluating the concepts were pretty standard Wichita-produced single engine piston aircraft reconfigured for the purpose. The technology was a variation in the field of boundary layer control (with acronym blc), aptly termed circulation control because of the emphasis on increasing lift as opposed to reducing drag as in some blc approaches. The lift enhancement was achieved for the most part by blowing high energy air over deflected trailing edge devices, giving slower speeds for landing and, in the case of the research airplanes, takeoff as well. In the production, high thrust fighter aircraft the blowing was applied for landing only, providing balanced takeoff and landing distances with less wing area and allowing the planes to get going to supersonic speeds. Certainly the leading edge (pun intended) technology used to do this was derived directly from the work of a truly international group once convened in the old cowtown to try to expand the aeronautical envelope.