So Much Accomplished...

As 2003 draws to a close, NASA Dryden Flight Research Center researchers have completed a milestone series of evaluation flights for a revolutionary flight control system that could enable future aircraft suffering major system failures or combat damage to be flown to a safe, controlled landing. The Intelligent Flight Control System, aboard a highly-modified NASA F-15B, focuses on development of "self-learning" neural network software for aircraft control computers. In its final form, the software would compare data from how the aircraft and its systems are operating with a database of how it would normally operate, and automatically adjust the flight controls to compensate for any damage or inoperative control surfaces or systems.

In April, a joint program of the Air Force Research Laboratory, NASA Dryden and Boeing Phantom Works completed the first phase of a project seeking to determine the advantages of twisting flexible wings for primary maneuvering roll control at transonic and supersonic speeds. The Active Aeroelastic Wing employs conventional control surfaces such as ailerons and leading-edge flaps to aerodynamically induce twist. From flight test and simulation data, the program will develop structural modeling techniques and tools to help design lighter, more flexible high aspect-ratio wings for future high-performance aircraft. Greater freedom in wing design will enable more economical operation or greater payload capability. In all, 50 test missions were flown in the modified, highly instrumented F/A-18 over the course of five months.

A milestone in the development of high-altitude, long-endurance remotely operated aircraft occurred in June with the inaugural flight of NASA's Altair, the first unmanned aerial vehicle (UAV) to feature triple-redundant flight systems and avionics for increased reliability. The one-of-a-kind aircraft will initially be used to evaluate various new control, communications and collision-avoidance technologies that are critical to enabling UAVs to fly safely in national airspace with manned aircraft. Later, NASA hopes to use the Altair for a variety of environmental science missions that are often too dangerous, difficult or lengthy for piloted aircraft to perform.

This fall, a Dryden designed and built small-scale aircraft flew the first known demonstration of propulsive power delivered by an invisible, ground-based laser. The model plane, with its five-foot wingspan, weighs only 11 ounces and is constructed from balsa wood and carbon fiber tubing covered with Mylar film. It is radio-controlled. The team of researchers from Dryden, Marshall Space Flight Center, Huntsville, Ala. , and the University of Alabama, Huntsville,  conducted the flight at Marshall and directed the laser's energy beam at specially designed photovoltaic cells carried onboard to power an electric motor turning the plane's propeller. The demonstration was a key step toward the capability to beam power to an aircraft aloft. Without the need for onboard fuel or batteries, such an airplane could carry scientific or communication equipment and stay in flight indefinitely.

NASA's Airborne Science Program, based at Dryden, has had a busy year supporting missions around the globe. The DC-8 began the year in Kiruna, Sweden, carrying instruments used to measure ozone and other atmospheric gases. From the snowy European landscape, the aircraft moved to the Rockies where it participated in a mission to study the role of snow-cover on Earth's weather and climate. The study of the snowpack during February and March will lead to improved forecasts of springtime water supply and snow melt floods. The DC-8 flew a coastal eddies mission off southern California in April. The aircraft carried instruments that captured  images of the eddies to measure the motion caused by the currents and monitor the movement of pollutants that originate on land. The aircraft surpassed 6,000 science flight hours during a spring study that collected aerosols along the California coast.

As 2004 nears, Dryden researchers are readying the X-43A for flights that could reach 10 times the speed of sound next year.

FMI: www.dfrc.nasa.gov