Eric T. Yerly

Date of Award


Document Type


Degree Name

Master of Science


Department of Aeronautics and Astronautics

First Advisor

Anthony M. DeLuca, PhD.


"This research compares the stability and roll characteristics of an X-56A using AFRL’s Variable Camber Complaint wing technology to actively change wing camber compared to conventional ailerons deflected at set angles. An analysis of the stability and roll characteristics was modeled using a 3-D vortex lattice theory simulation, and that data was compared to wind tunnel testing to verify and validate the model results. Wind tunnel data was collected using 19 inch 3-D printed scale models with wings fabricated with a pre-determined percentage of camber deformation, as well as models with fixed aileron deflections. The full span model changed camber from the original airfoil 5% between the root and tip; the 1% camber model changed camber a total of 5% starting from the root, scaled at 1% per foot; and the quick camber change model changed camber 5% from the root over a scale adjusted 2 foot span. Wind tunnel testing was performed at a Reynolds number range from 30,000 to 150,000. Testing indicated at high speeds and low angles of attack, the camber deformed wings produced a roll moment and roll rate equivalent to, or greater than conventional ailerons. At larger angles of attack and low forward speeds, roll reversal and early wing stall were encountered due to the decreased camber. Because of early onset stall, the camber deformed wing had a lower lift coefficient with increased drag. The camber deformed models did not result in aerodynamic moment instability; however, they did demonstrate a decrease in roll and pitch stability. The 3-D model predicted accurate trends in roll and stability, but could not model viscous effects due to the inviscid nature of the simulation. Manual skin friction corrections yield more accurate drag results, increasing the ability for Tornado to model the behavior of the X-56A.

AFIT Designator


DTIC Accession Number