NASA’S CONTRIBUTIONS TO AERONAUTICS

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S THIS BOOK GOES TO PRESS, the National Aeronautics and Space Administration (NASA) has passed beyond the half cen­tury mark, its longevity a tribute to how essential successive Presidential administrations—and the American people whom they serve—have come to regard its scientific and technological expertise. In that half century, flight has advanced from supersonic to orbital veloc­ities, the jetliner has become the dominant means of intercontinental mobility, astronauts have landed on the Moon, and robotic spacecraft developed by the Agency have explored the remote corners of the solar system and even passed into interstellar space.

Born of a crisis—the chaotic aftermath of the Soviet Union’s space triumph with Sputnik—NASA rose magnificently to the challenge of the emergent space age. Within a decade of NASA’s establishment, teams of astronauts would be planning for the first lunar landings, accom­plished with Neil Armstrong’s "one small step” on July 20, 1969. Few events have been so emotionally charged, and none so publicly visible or fraught with import, as his cautious descent from the spindly lit­tle Lunar Module Eagle to leave his historic boot-print upon the dusty plain of Tranquillity Base.

In the wake of Apollo, NASA embarked on a series of space initia­tives that, if they might have lacked the emotional and attention-getting impact of Apollo, were nevertheless remarkable for their accomplish­ment and daring. The Space Shuttle, the International Space Station, the Hubble Space Telescope, and various planetary probes, landers, rov­ers, and flybys speak to the creativity of the Agency, the excellence of its technical personnel, and its dedication to space science and exploration.

But there is another aspect to NASA, one that is too often hidden in an age when the Agency is popularly known as America’s space agency and when its most visible employees are the astronauts who courageously

rocket into space, continuing humanity’s quest into the unknown. That hidden aspect is aeronautics: lift-borne flight within the atmosphere, as distinct from the ballistic flight of astronautics, out into space. It is the first "A” in the Agency’s name, and the oldest-rooted of the Agency’s tech­nical competencies, dating to the formation, in 1915, of NASA’s lineal predecessor, the National Advisory Committee for Aeronautics (NACA). It was the NACA that largely restored America’s aeronautical primacy in the interwar years after 1918, deriving the airfoil profiles and con­figuration concepts that defined successive generations of ever-more – capable aircraft as America progressed from the subsonic piston era into the transonic and supersonic jet age. NASA, succeeding the NACA after the shock of Sputnik, took American aeronautics across the hyper­sonic frontier and onward into the era of composite structures, elec­tronic flight controls and energy-efficient flight.

As with the first in this series, this second volume traces con­tributions by NASA and the post-Second World War NACA to aeronautics. The surveys, cases, and biographical examinations pre­sented in this work offer just a sampling of the rich legacy of aero­nautics research having been produced by the NACA and NASA. These include

• Atmospheric turbulence, wind shear, and gust research, subjects of crucial importance to air safety across the spectrum of flight, from the operations of light general – aviation aircraft through large commercial and super­sonic vehicles.

• Research to understand and mitigate the danger of light­ning strikes upon aerospace vehicles and facilities.

• The quest to make safer and more productive skyways via advances in technology, cross-disciplinary integration of developments, design innovation, and creation of new operational architectures to enhance air transportation.

• Contributions to the melding of human and machine, via the emergent science of human factors, to increase the safety, utility, efficiency, and comfort of flight.

• The refinement of free-flight model testing for aero­dynamic research, the anticipation of aircraft behavior, and design validation and verification, complementing traditional wind tunnel and full-scale aircraft testing.

• The evolution of the wind tunnel and expansion of its capabilities, from the era of the slide rule and subsonic flight to hypersonic excursions into the transatmosphere in the computer and computational fluid dynamics era.

• The advent of composite structures, which, when cou­pled with computerized flight control systems, gave air­craft designers a previously unknown freedom enabling them to design aerospace vehicles with optimized aero­dynamic and structural behavior.

• Contributions to improving the safety and efficiency of general-aviation aircraft via better understanding of their unique requirements and operational circum­stances, and the application of new analytical and tech­nological approaches.

• Undertaking comprehensive flight research on sustained supersonic cruise aircraft—with particular attention to their aerodynamic characteristics, airframe heating, use of integrated flying and propulsion controls, and eval­uation of operational challenges such as inlet "unstart,” aircrew workload—and blending them into the predomi­nant national subsonic and transonic air traffic network.

• Development and demonstration of Synthetic Vision Systems, enabling increased airport utilization, more effi­cient flight deck performance, and safer air and ground aircraft operations.

• Confronting the persistent challenge of atmospheric icing and its impact on aircraft operations and safety.

• Analyzing the performance of aircraft at high angles of attack and conducting often high-risk flight-testing to study their behavior characteristics and assess the value of developments in aircraft design and flight control technologies to reduce their tendency to depart from controlled flight.

• Undertaking pathbreaking flight research on VTOL and V/STOL aircraft systems to advance their ability to enter the mainstream of aeronautical development.

• Conducting a cooperative international flight-test program to mutually benefit understanding of the potential, behav­ior, and performance of large supersonic cruise aircraft.

As this sampling—far from a complete range—of NASA work in aeronautics indicates, the Agency and its aeronautics staff spread across the Nation maintain a lively interest in the future of flight, benefitting NASA’s reputation earned in the years since 1958 as a national reposi­tory of aerospace excellence and its legacy of accomplishment in the 43-year history of the National Advisory Committee for Aeronautics, from 1915 to 1958.

As America enters the second decade of the second century of winged flight, it is again fitting that this work, like the volume that precedes it, be dedicated, with affection and respect, to the men and women of NASA, and the NACA from whence it sprang.

Dr. Richard P. Hallion

August 25, 2010

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