AFRL Researchers Test Boundary Layer Data System

  • Published
  • By Holly Jordan, AFRL/RBOO
  • Air Vehicles Directorate
WRIGHT-PATTERSON AIR FORCE BASE, Ohio --  AFRL researchers, in conjunction with Northrop Grumman and Washington State University (WSU), completed a series of flights to test the recently developed Boundary Layer Data System (BLDS-A). The BLDS-A is an instrument designed to characterize aircraft boundary layer--the thin layer of air at the surface of the aircraft. In this region, the air flowing over a surface transitions from laminar (smooth) to turbulent. Understanding boundary layer properties is therefore critical to understanding how an aircraft performs, especially in terms of lift and drag. The BLDS-A is a small, lightweight, self-contained unit that is easily attached (via removable structural adhesive) to virtually any location on an aircraft surface.

The BLDS-A instrument has built-in power, data acquisition, and data storage capacity, which means there is no need to route pressure tubes or instrumentation wires to the device. The unit's small size enables it to collect accurate in-flight data with no interference to aircraft operations. To test the BLDS-A, researchers attached the device to a Northrop Grumman-owned Cessna TU206 aircraft, which subsequently flew a total of eight sorties wherein the BLDS-A successfully collected boundary layer data. WSU researchers then analyzed the data.

In addition to gathering data, the flight test confirmed BLDS-A system functionality. As a result, the instrument will be part of an upcoming SensorCraft wing flight test. The data gathered from the BLDS-A flight tests will help researchers better understand boundary layer behavior on the SensorCraft wing test article mounted underneath the Scaled Composites, LLC, White Knight aircraft. The BLDS-A flight test effort is part of Northrop Grumman's Aerodynamic Efficiency Improvement program, which seeks to develop and test aircraft structural and aerodynamic technologies for future intelligence, surveillance, and reconnaissance vehicles such as the SensorCraft concept.