Flight experiments on the effects of step excrescences on swept-wing transition Academic Article uri icon


  • A 30° swept-wing model with a movable, leading-edge extending to 15% chord is used in flight tests to study the effect of two-dimensional, step excrescences on swept-wing transition, where stationary-crossflow waves are typically the dominant instability. Transport unit Reynolds numbers are achieved using a Cessna O-2A Skymaster. Forward- and aft-facing steps are modulated in-flight. Pressure measurements are compared with CFD. Infrared thermography is used to globally detect boundary-layer transition. When the 2-D pressure gradient matches the unswept case, the swept-wing case has a lower Rekk,crit. However, there is still potential to relax conventional, laminar-flow tolerances for steps. © 2014 Inderscience Enterprises Ltd.

author list (cited authors)

  • Jr., G., Crawford, B. K., Tufts, M. W., Saric, W. S., & Reed, H. L.

citation count

  • 4

publication date

  • January 2014