Structural loads testing on the Active Aeroelastic Wing F-18 has begun in the Flight Loads Laboratory at NASA's Dryden flight Research Center, Edwards, California. The heavily modified and instrumented F-18A entered the Loads Lab in mid-March, 2001, for fit checks of loads hardware and instrumentation checkout prior to initiation of actual structural loads testing. The F-18A will be undergoing loads testing on its modified wings for almost six months, followed by extensive systems tests and simulation before flight tests begin. The AAW project goal is to demonstrate improved aircraft roll control through aerodynamically-induced wing twist on a full-scale aircraft. The F-18A has been modified with additional actuators, a split leading edge flap and thinner wing skins. The traditional wing control surfaces—trailing edge ailerons and the outboard leading edge flaps—are used to provide the aerodynamic force needed to twist or ''warp'' the wing. AAW research could enable thinner, higher aspect-ratio wings on future aircraft which could result in reduced aerodynamic drag, allowing greater range or payload and improved fuel efficiency.