An advanced aeroelastic wing and laser-based gust monitoring device is under test at NASA Dryden Flight Research Center in California as part of efforts to create better design tools for future airliner wings.
The University of California, Los Angeles, gust monitoring and aeroelasticity (GMA) experiment is investigating the dynamic response of a flexible wing to in-flight manoeuvres and atmospheric gust winds, as well as the operation of a new gust-measuring device. The work is also designed to aid improved understanding of aeroelastic wing flutter.
The results will help to test and verify new aeroelastic modelling techniques under development that will be used to develop and combine active gust alleviation and flutter suppression control algorithms.
The aim of this research, with a parallel Active Aeroelastic Wing (AAW) NASA-Boeing flight test programme expected to begin in 2001, is the development of lighter, flexible wing structures.
In theory, these wings would twist in flight, enabling faster and more efficient roll control than with conventional ailerons and other flight controls.
The principle would build on the inherent flexibility of a wing and reduce the requirements for structural stiffness. The wing shape would be dictated by leading and trailing edge control surfaces. NASA believes that an AAW would reduce overall drag and lead to a potential 30% drop in take-off weight.
While the AAW will use a NASA Boeing F/A-18A rewinged on one side with an AAW test article, the GMA experiment is mounted on the Flight Test Fixture (FTF-II) of Dryden's F-15B Aerodynamic Research Test Bed aircraft. A small, flexible, 45cm (18in)-long, 10cm-chord test wing and low-power laser is mounted on the FTF-II which will be flown at speeds up to Mach 0.8 and altitudes up to 20,000ft (6,000m).
Source: Flight International
