SPACEPHOTOS

A modified F/A-18A undergoes wing torsion or twist testing in the Flight Dynamics Laboratory at NASA's Dryden Flight Research Center, Edwards, California. The tests simulate the amount of twisting that the wing might encounter during flight in the upcoming Active Aeroelastic Wing (AAW) flight research project at Dryden. During the tests, powerful hydraulic jacks attached to as fixture mounted on the tip of the F/A-18's left wing literally twist the wing to determine its flexibility, while numerous strain gauges and other devices record the stresses on the wing structure. The joint Air Force-NASA AAW program will seek to determine the advantages of using flexible wings for primary maneuvering roll control at transonic and supersonic speeds, with traditional control surfaces such as ailerons and leading-edge flaps used to induce the twist. Researchers believe the concept could lead to lighter, more flexible wings on future high-performance aircraft, which could translate to more economical operation or greater payload capability. AAW flight tests are due to begin late this year or early in 2002.