Category NASA’S CONTRIBUTIONS TO AERONAUTICS

The advent of vertical flight required mastery of aerodynamics, pro­pulsion, and flight control technology. In the evolution of flight charac­terized by progressive development of the autogiro, helicopter, and various convertiplanes, the NACA and NASA have played a predom­inant role. NASA developed the theoretical underpinning for vertical flight, evaluated requisite technologies and research vehicles, and expanded the knowledge base supporting V/STOL flight technology.

NE OF THE MAJOR ACCOMPLISHMENTS in the history of avi­ation has been the development of practical Vertical Take-Off and Landing (VTOL) aircraft, exemplified by the emergence of the helicopter in the 1930s and early 1940s, and the vectored-thrust

jet airplane of the 1960s. Here indeed was a major challenge that con­fronted flight researchers, aeronautical engineers, military tacticians, and civilian planners for over 50 years, particularly those of the National Aeronautics and Space Administration (NASA) and its predecessor, the National Advisory Committee for Aeronautics (NACA). While perhaps not regarded by aviation aficionados as being as glamorous as the exper­imental craft that streaked to new speeds and altitudes, early vertical flight testbeds were likewise revolutionary at the other end of the perfor­mance spectrum, in vertical ascents and descents, low-speed controlla­bility, and hover, areas challenging accepted knowledge and practice in aerodynamics, propulsion, and flight controls and controllability.[1330]

The accomplishment of vertical flight was as challenging as inventing the airplane itself. Only four decades after Kitty Hawk were vertical take­off, hovering, and landing aircraft beginning to enter service. These were, of course, the first helicopters: successors to the interim rotary wing auto­giro that relied on a single or multiple rotors to give them Vertical/Short

Take-Off and Landing (V/STOL) performance. Before the end of the Second World War, the helicopter had flown in combat, proved its value as a life­saving craft, and shown its adaptability for both land – and sea-based operation.[1331] The faded promises of many machines litter the path to the modern V/STOL vehicle. The dedicated research accompanying this work nevertheless led to a class of flight craft that have expanded the use of civil and military aeronautics, saving the lives of nearly a half million people over the last seven decades. The oil rigger in the Gulf going on leave, the yachtsman waiting for rescue, and the infantryman calling in gunships to fend off attack can all thank the flight researchers, particularly those of the NACA and NASA, who made the VTOL aircraft possible.[1332]

Helicopters matured significantly during the Korean war, setting the stage for their pervasive employment in the war in Southeast Asia a decade later.[1333] Helicopters revolutionized warfare and became the iconic image of the Vietnam war. On the domestic front, outstanding helicop­ter research was being carried on at NASA Langley. Of particular note were the contributions of researchers and test pilots such as Jack Reeder, John P. Campbell, Richard E. Kuhn, Marion O. McKinney, and Robert

H. Kirby. In the late 1950s, military advisers realized how much of the Nation’s defense structure depended on a few large airbases and a few large aircraft carriers. Military interests were driven by the objective of achieving operations into and out of unprepared remotely dispersed sites independent of conventional airfields. Meanwhile, commercial air transportation organizations were pursuing ways to cut the amount of real estate required to accommodate new aircraft and long airstrips.[1334]

Since NASAs inception in 1958, its researchers at various Centers have advanced the knowledge base of V/STOL technology via many special­ized test aircraft and flying techniques. Some key discoveries include the realization that V/STOL aircraft must be designed with good Short Take­Off and Landing (STOL) performance capability to be cost-effective, and that, arguably, the largest single obstacle to the implementation of STOL powered-lift technology for civil aircraft is the increasingly objection­able level of aircraft-generated noise at airports close to populated areas.

But NASA interest in fixed wing STOL and VTOL convertiplanes predates formation of the Agency, going back to the unsuccessful com­bined rotor and wing design by Emile and Henry Berliner tested at College Park Airport, MD, in the early 1920s. In the late 1930s and early 1940s, NACA researcher Charles Zimmerman undertook pioneer­ing research on such craft, his interest leading to the Vought V-173, popularly known as the "Flying Flapjack,” because of its peculiar near­circular wing shape. It led to an abortive Navy fighter concept, the Vought XF5U-1, which was built but never flown. The V-173, however, contrib­uted notably to the emerging understanding of V/STOL aircraft chal­lenges and performance. Aside from this sporadic interest, the Agency’s research staff did not place great emphasis upon such studies until the postwar era. Then, beginning in the early 1950s, a veritable explosion of interest followed, with a number of design studies and flight-test

programs undertaken at Langley and Ames laboratories (later the NASA Langley and Ames Research Centers). This interest corresponded to ris­ing interest in the military in the possibility of vertical flight vehicles for a variety of missions.

For example, the U. S. Navy sponsored two unsuccessful experimen­tal "Pogo” tail-sitting turboprop-powered VTOL fighters: the Lockheed XFV-1 and the Convair XFY-1. Only the XFY-1 subsequently operated in true VTOL mode, and flight trials indicated that neither represented a
reasonable approach to practical VTOL flight. The Air Force developed a pure-jet equivalent: the VTOL delta-winged Ryan X-13. Though widely demonstrated (even outside the Pentagon), it was equally impracticable.[1335] The U. S. Army’s Transportation and Research Engineering Command sponsored ducted-fan flying jeep and other saucerlike circular flying platforms by Avro and Hiller, with an equivalent lack of success. Overall, the Army’s far-seeing V/STOL testbed program, launched in 1956 and undertaken in cooperation with the U. S. Navy’s Office of Naval Research, advanced a number of so-called "VZ”-designated research aircraft explor­ing a range of technical approaches to V/STOL flight.[1336] NATO planners envisioned V/STOL close-air support, interdiction, and nuclear attack aircraft. This interest eventually helped spawn the British Aerospace Harrier strike fighter of the late 1960s and other designs that, though they entered flight-testing, did not prove suitable for operational service.[1337]

The United States Pilot Evaluation Team (USPET)[1477] arrived in Moscow on Sunday, September 6, 1998, and was met by Professor Alexander Pukhov and a delegation of Tupolev officials. (Ill fortune had struck the team when NASA Langley research pilot Robert Rivers severely broke his right leg and ankle 2 weeks before departure. Because visas for work in Russia required 60 days’ lead time and because no other pilot could be prepared in time, Rivers remained on the team, though it required a great deal of perseverance to obtain NASA approval. Tupolev pre­sented relatively few obstacles, by contrast, to Rivers’s participation.) Pukhov was the Tupolev Manager for the Tu-144 experiment and a for­mer engineer on the original design team for the airplane. At Pukhov’s insistence, USPET was billeted in Zhukovsky at the former KGB san­itarium. Sanitaria in the Soviet Union were rest and vacation spas for the various professional groups, and the KGB sanitarium was similar to a large hotel. The sanitarium was minutes from the Zhukovsky Air

Development Center and saved hours of daily commute time that oth­erwise might have been wasted had the team been housed in Moscow.

The next day began a very intense training period lasting 2 weeks but was punctuated September 15 by the first flight by American pilots, a subsonic sojourn. The training was complicated by the language differ­ences but was facilitated by highly competent Russian State Department translators. Nevertheless, humorous if not frustrating problems arose when nontechnical translators attempted to translate engineering and piloting jargon with no clear analogs in either language. The training consisted of one-on-one sitdown sessions with various Tu-144 systems experts using manuals and charts written in Russian. There were no English language flight or systems manuals for the Tu-144, and USPET’s attempt over the summer to procure a translated Tu-144 flight manual was unsuccessful. Training included aircraft systems, life support, and flight operations. Because flights would achieve altitudes of 60,000 feet and because numerous hull penetrations had occurred to accommodate the instrumentation system, all members of the flightcrew wore partial pressure suits. Because of the experimental nature of the flights, a man­ual bailout capability had been incorporated in the Tu-144. This involved dropping through a hatch just forward of the mammoth engine inlets. The hope was that the crewmember would pass between the two banks of engines without being drawn into the inboard inlets. Thankfully, this theory was never put to the test.

Much time was spent with the Tupolev flightcrew for the experi­ment, and great trust and friendship ensued. Tupolev chief test pilot Sergei Borisov was the pilot-in-command for all of the flights. Victor Pedos was the navigator, in actuality a third pilot, and Anatoli Kriulin was the flight engineer. Tupolev’s chief flight control engineer, Vladimir Sysoev, spent hours each day with USPET working on the test plan for each pro­posed flight. Sysoev and Borisov represented Tupolev in the negotiations to perform the maneuvers requested by the various researchers.[1478] An effective give-and-take evolved as the mutual trust grew. From Tupolev’s perspective, the Tu-144 was a unique asset, into which the fledgling free- market company had invested millions of dollars. It provided badly needed funds at a time when the Russian economy was struggling, and

the payments from NASA via Boeing and IBP were released only at the completion of each flight. The Tupolev crewmembers could not afford to risk the airplane. At the same time, they were anxious to be as coop­erative as possible. Careful and inventive planning resulted in nearly all of the desired test points being flown.

James Banke

Since 1926 and the passage of the Air Commerce Act, the Federal Government has had a vital commitment to aviation safety. Even before this, however, the NACA championed regulation of aeronau­tics, the establishment of licensing procedures for pilots and aircraft, and the definition of technical criteria to enhance the safety of air operations. NASA has worked closely with the FAA and other aviation organizations to ensure the safety of America’s air transport network.

HEN THE FIRST AIRPLANE LIFTED OFF from the sands of Kitty Hawk during 1903, there was no concern of a midair collision with another airplane. The Wright brothers had the North Carolina skies all to themselves. But as more and more aircraft found their way off the ground and then began to share the increasing num­ber of new airfields, the need to coordinate movements among pilots quickly grew. As flight technology matured to allow cross-country trips, methods to improve safe navigation between airports evolved as well. Initially, bonfires lit the airways. Then came light towers, two-way radio, omnidirectional beacons, radar, and—ultimately—Global Positioning System (GPS) navigation signals from space.[181]

Today, the skies are crowded, and the potential for catastrophic loss of life is ever present, as more than 87,000 flights take place each day over the United States. Despite repeated reports of computer crashes or bad weather slowing an overburdened national airspace system, air- related fatalities remain historically low, thanks in large part to the technical advances developed by the National Aeronautics and Space Administration (NASA), but especially to the daily efforts of some 15,000 air traffic controllers keeping a close eye on all of those airplanes.[182]

All of those controllers work for, or are under contract to, the Federal Aviation Administration (FAA), which is the Federal agency respon­sible for keeping U. S. skyways safe by setting and enforcing regula­tions. Before the FAA (formed in 1958), it was the Civil Aeronautics Administration (formed in 1941), and even earlier than that, it was the Department of Commerce’s Aeronautics Bureau (formed in 1926). That that administrative job today is not part of NASA’s duties is the result of decisions made by the White House, Congress, and NASA’s prede­cessor organization, the National Advisory Committee for Aeronautics (NACA), during 1920.[183]

At the time (specifically 1919), the International Commission for Air Navigation had been created to develop the world’s first set of rules for governing air traffic. But the United States did not sign on to the con­vention. Instead, U. S. officials turned to the NACA and other organiza­tions to determine how best to organize the Government for handling

all aspects of this new transportation system. The NACA in 1920 already was the focal point of aviation research in the Nation, and many thought it only natural, and best, that the Committee be the Government’s all­inclusive home for aviation matters. A similar organizational model existed in Europe but didn’t appear to some with the NACA to be an ideal solution. This sentiment was most clearly expressed by John F. Hayford, a charter member of the NACA and a Northwestern University engineer, who said during a meeting, "The NACA is adapted to function well as an advisory committee but not to function satisfac­torily as an administrative body.”[184]

So, in a way, NASA’s earliest contribution to making safer skyways was to shed itself of the responsibility for overseeing improvements to and regulating the operation of the national airspace. With the FAA secure in that management role, NASA has been free to continue to play to its strengths as a research organization. It has provided techni­cal innovation to enhance safety in the cockpits; increase efficiencies along the air routes; introduce reliable automation, navigation, and com­munication systems for the many air traffic control (ATC) facilities that dot the Nation; and manage complex safety reporting systems that have required creation of new data-crunching capabilities.

This case study will present a survey in a more-or-less chronolog­ical order of NASA’s efforts to assist the FAA in making safer skyways. An overview of key NASA programs, as seen through the eyes of the FAA until 1996, will be presented first. NASA’s contributions to air traffic safety after the 1997 establishment of national goals for reducing fatal air acci­dents will be highlighted next. The case study will continue with a sur­vey of NASA’s current programs and facilities related to airspace safety and conclude with an introduction of the NextGen Air Transportation System, which is to be in place by 2025.

When NASA’s Aviation Safety Program was begun in 1997, the agency joined with a large group of aviation-related organizations from Government, industry, and academia in forming a Commercial Aviation Safety Team (CAST) to help reduce the U. S. com­mercial aviation fatal accident rate by 80 percent in 10 years. During those 10 years, the group analyzed data from some 500 accidents and thou­sands of safety incidents and helped develop 47 safety enhancements.[249] In 2008, the group could boast that the rate had been reduced by 83 percent, and for that, CAST was awarded avi­ation’s most prestigious honor, the Robert J. Collier Trophy.

The interface between humans and technology was no less important for those early pioneers, who, for the first time in history, were start­ing to reach for the sky. Human factors research in aeronautics did not, however, begin with the Wright brothers’ first powered flight in 1903; it began more than a century earlier.

Much of this early work dealt with the effects of high altitude on humans. At greater heights above the Earth, barometric pressure decreases. This allows the air to expand and become thinner. The net effect is diminished breathable oxygen at higher altitudes. In humans operating high above sea level without supplemental oxygen, this trans­lates to a medical condition known as hypoxia. The untoward effects on humans of hypoxia, or altitude sickness, had been known for centu­ries—long before man ever took to the skies. It was a well-known entity to ancient explorers traversing high mountains, thus the still commonly used term mountain sickness.[298]

The world’s first aeronauts—the early balloonists—soon noticed this phenomenon when ascending to higher altitudes; eventually, some of the early flying scientists began to study it. As early as 1784, American physician John Jeffries ascended to more than 9,000 feet over London with French balloonist Jean Pierre Blanchard.[299] During this flight, they recorded changes in temperature and barometric pressure and became perhaps the first to record an "aeromedical” problem, in the form of ear pain associated with altitude changes.[300] Another early flying doctor, British physician John Shelton, also wrote of the detrimental effects of high-altitude flight on humans.[301]

During the 1870s—with mankind’s first powered, winged human flight still decades in the future—French physiologist Paul Bert conducted important research on the manner in which high – altitude flight affects living organisms. Using the world’s first pressure chamber, he studied the effects of varying barometric pressure and oxygen levels on dogs and later humans—himself included. He conducted 670 experiments at simulated altitudes of up to 36,000 feet. His findings clarified the effects of high-altitude conditions on humans and established the requirement for supplemental oxygen at higher altitudes.[302] Later studies by other researchers followed, so that by the time piloted flight in powered aircraft became a reality at Kitty Hawk, NC, on December 17, 1903, the scientific community already had a substantial amount of knowledge concerning the physiology of high-altitude flight. Even so, there was much more to be learned, and additional research in this important area would continue in the decades to come.

From the foregoing, it is clear that NASA’s human factors research has over the past decades specifically focused on aviation safety. This work, however, has also maintained an equally strong focus on improving the human-machine interface of aviation professionals, both in the air and on the ground. NASA has accomplished this through its many highly devel­oped programs that have emphasized human-centered considerations in the design and engineering of increasingly complex flight systems.

These human factors considerations in systems design and integration have directly translated to increased human performance and efficiency and, indirectly, to greater flight safety. The scope of these contributions is [421] [422]

best illustrated by briefly discussing a representative sampling of NASA programs that have benefitted aviation in various ways, including the Man – Machine Integration Design and Analysis System (MIDAS), Controller – Pilot Data Link Communications (CPDLC), NASA’s High-Speed Research (HSR) program, the Advanced Air Transportation Technologies (AATT) program, and the Agency’s Vision Science and Technology effort.

The selection of blunt capsule designs for the Mercury, Gemini, and Apollo programs resulted in numerous investigations of the dynamic stability and recovery of such shapes. Nonlinear, unstable varia­tions of aerodynamic forces and moments with angle of attack and sideslip were known to exist for these configurations, and extensive conventional force tests, dynamic free-flight model tests, and analyti­cal studies were conducted to define the nature of potential problems that might be encountered during atmospheric reentry. At Ames, the supersonic and hypersonic free-flight aerodynamic facilities have been used to observe dynamic stability characteristics, extract aero­dynamic data from flight tests, provide stabilizing concepts, and develop mathematical models for flight simulation at hypersonic and supersonic speeds.

Meanwhile, at Langley, researchers in the Spin Tunnel were con­ducting dynamic stability investigations of the Mercury, Gemini, and Apollo capsules in vertically descending subsonic flight.[492]

Results of these studies dramatically illustrated potential dynamic stability issues during the spacecraft recovery procedure. For example, the Gemini capsule model was very unstable; it would at various times oscillate, tumble, or spin about a vertical axis with its symmetrical axis tilted as much as 90 degrees from the vertical. However, the deployment of a drogue parachute during any spinning or tumbling motions quickly terminated these unstable motions at subsonic speeds. Extensive tests of various drogue-parachute configurations resulted in definitions of acceptable parachute bridle-line lengths and attachment points. Spin Tunnel results for the Apollo command module configuration were even more dramatic. The Apollo capsule with blunt end forward was dynam­ically unstable and displayed violent gyrations, including large oscilla­tions, tumbling, and spinning motions. With the apex end forward, the capsule was dynamically stable and would trim at an angle of attack of about 40 degrees and glide in large circles. Once again, the use of a drogue parachute stabilized the capsule, and the researchers also found that retention of the launch escape system, with either a drogue para­chute or canard surfaces attached to it, would prevent an unacceptable apex-forward trim condition during launch abort.

Following the Apollo program, NASA conducted a considerable effort on unpiloted space probes and planetary exploration. In the Langley Spin Tunnel, several planetary-entry capsule configurations were tested to evaluate their dynamic stability during descent, with a priority in simulating descent in the Martian atmosphere.[493] Studies also included assessments of the Pioneer Venus probe in the 1970s. These tests pro­vided considerable design information on the dynamic stability of a vari­ety of potential planetary exploration capsule shapes. Additional studies

of the stability characteristics of blunt, large-angle capsules were con­ducted in the late 1990s in the Spin Tunnel.

As the new millennium began, NASA’s interests in piloted and unpi­loted planetary exploration resulted in additional studies of dynamic sta­bility in the Spin Tunnel. Currently, the tunnel and its dynamic model testing techniques are supporting NASA’s Constellation program for

lunar exploration. Included in the dynamic stability testing are the Orion launch abort vehicle, the crew module, and alternate launch abort systems.[494]

One of the more impressive advances in aerospace capability in the last few years has been the acceptance and accelerated development of remotely piloted unmanned aerial vehicles (UAVs) by the military. The progress in innovative hardware and software products to support this focus has truly been impressive and warrants a consideration that properly scaled free – flight models have reached the appropriate limits of development. In com­parison to today’s capabilities, the past equipment used by the NACA and NASA seems primitive. It is difficult to anticipate hardware breakthroughs in free-flight model technologies beyond those currently employed, but NASA’s most valuable contributions have come from the applications of the models to specific aerospace issues—especially those that require years of difficult research and participation in model-to-flight correlation studies.

Changes in the world situation are now having an impact on aero­nautics, with a trickle-down effect on technical areas such as free-flight

testing. The end of the Cold War and industrial mergers have resulted in a dramatic reduction in new aircraft designs, especially for uncon­ventional configurations that would benefit from free-flight testing. Reductions in research budgets for industry and NASA have further aggravated the situation.

These factors have led to a slowdown in requirements for the ongoing NASA capabilities in free-flight testing at a time when rollover changes in the NASA workforce is resulting in the retirements of specialists in this and other technologies without adequate transfer of knowledge and mentoring to the new research staffs. In addition, planned closures of key NASA facilities will challenge new generations of researchers to reinvent the free-flight capabilities discussed herein. For example, the planned demolition of the Langley Full-Scale Tunnel in 2009 will terminate that historic 78-year-old facility’s role in providing free-flight testing capa­bility, and although exploratory free-flight tests have been conducted in the much smaller test section of the Langley 14- by 22-Foot Tunnel, it remains to be seen if the technique will continue as a testing capa­bility. Based on the foregoing observations, NASA will be challenged to provide the facilities and expertise required to continue to provide the Nation with contributions from free-flight models.

Is the wind tunnel obsolete? In a word, no. But the value and merit of the tunnel in the early 21st century must be evaluated in the light of manifold other techniques that researchers can now employ. The range of these new techniques, particularly CFD, coupled with the seeming maturity of the airplane, has led some observers to conclude that there is little need for extensive investment in research, development, and infrastructure.[630] That facile assumption has been carried over into the question of whether there is a continued need for wind tunnels. It brings into question the role of the wind tunnel in contemporary aero­space research and development.

A 1988 New York Times article titled "In the Space Age, the Old Wind Tunnel Is Being Left Behind” proclaimed "aerospace engineers have hit

a dead end in conventional efforts to test designs for the next generation of spaceships, planetary probes and other futuristic flying machines.” The technology for the anticipated next generation in spacecraft technol­ogy that would appear in the 21st century included speeds in the escape velocity range and the ability to maneuver in and out of planetary atmo­spheres rather than the now-familiar single direction and uncontrolled descents of today. At the core of the problem was getting realistic flight data from a "nineteenth century invention used by the Wright brothers,” the wind tunnel. William I. Scallion of NASA Langley asserted, "We’ve pushed beyond the capacity of most of our ground facilities.” NASA, the Air Force, and various national universities began work on meth­ods to simulate the speeds, temperatures, stress, forces, and vibration challenging the success of these new craft. The proposed solutions were improved wind tunnels capable of higher speeds, the firing of small-scale models atop rockets into the atmosphere, and the dropping of small test vehicles from the Space Shuttle while in orbit.[631]

The need for new testing methods and facilities reflected the chang­ing nature of aerospace craft missions and design. Several programs per­ceived to be pathways to the future in the 1980s exemplified the need for new testing facilities. Proponents of the X-30 aerospace plane believed it would be able to take off and fly directly into space by reaching Mach 25, or 17,000 mph, while being powered by air-breathing engines. In 1988, wind tunnels could only simulate speeds up to Mach 12.5. NASA intended the Aeromanuevering Orbit Transfer Vehicle to be a low-cost "space tug” that could move payloads between high – and low-Earth orbits beginning in the late 1990s. The vehicle slowed itself in orbit by graz­ing the Earth’s outer atmosphere with an aerobrake, or a lightweight shield, rather than relying upon heavy retrorockets, a technique that was impossible to replicate in a wind tunnel. NASA planned to launch small models from the Space Shuttle for evaluation. The final program con­cerned new interplanetary probes destined for Mars; Jupiter; Saturn’s moon, Titan; and their atmospheres, which were much unlike Earth’s. They no longer just dropped back into Earth’s or another planet’s atmo­sphere from space. The craft required maneuverability and flexibility as incorporated into the Space Shuttle for better economy.[632]

NASA allocated funds for the demolition of unused facilities for the first time in the long history of the Agency in 2003. The process required that each of the Research Centers submit listings of target facilities.[633] NASA’s Assistant Inspector General for Auditing conducted a survey of the utilization of NASA’s wind tunnels at three Centers in 2003 and reported the findings to the directors of Langley, Ames, and Lewis and to the Associate Administrator for Aerospace Technology. Private indus­try and the Department of Defense spent approximately 28,000 hours in NASA tunnels in 2002. The number dwindled to 10,000 hours in 2003, dipping to about 2,500 hours in 2008. NASA managers acknowledged there was a direct correlation between a higher user fee schedule intro­duced in 2002 and the decline in usage. The audit also included the first complete list of tunnel closures for the Agency. Of the 19 closed facili­ties, NASA classified 5 as having been "mothballed,” with the remain­ing 14 being "abandoned.”[634]

Budget pressures also forced NASA to close running facilities. Unfortunately, NASA’s operation of the NFAC was short-lived when the Agency closed the facility in 2003. Recognizing the need for full-scale testing of rotorcraft and powered-lift V/STOL aircraft, the Air Force leased the facility in 2006 for use by the AEDC. The NFAC became operational again in 2008. Besides aircraft, the schedule at the NFAC accommodated nontraditional test subjects, including wind turbines, parachutes, and trucks.[635]

In 2005, NASA announced its plan to reduce its aeronautics budget by 20 percent over the following 5 years. The budget cuts included the closing of wind tunnels and other research facilities and the elimination of hundreds of jobs. NASA had spread thin what was left of the aero­nautics budget (down $54 million to $852 million) over too many pro­grams. NASA did receive a small increase in its overall budget to cover the costs of the new Moon-Mars initiative, which meant cuts in aviation – related research. In a hearing before the House Science Subcommittee

on Space and Aeronautics to discuss the budget cuts, aerospace industry experts and politicians commented on the future of fundamental aeronautics research in the United States. Dr. John M. Klineberg, a former NASA official and industry executive, asserted that the NASA aeronautics program was "on its way to becoming irrelevant to the future of aeronautics in this country and in the world.” Representative Dennis Kucinich, whose district included Cleveland, the home of NASA Glenn, warned that the United States was "going to take the ‘A’ out” of NASA and that the new Agency was "just going to be the National Space Administration.”[636]

Philip S. Anton, Director of the RAND Corporation’s Acquisition and Technology Policy Center, spoke before the Committee. RAND concluded a 3-year investigation that revealed that only 2 of NASA’s 31 wind tun­nels warranted closure.[637] As to the lingering question of the supremacy of CFD, Anton asserted that NASA should pursue wind tunnel facility, CFD, and flight-testing to meet national testing needs. RAND recom­mended a veritable laundry list of suggested improvements that ranged from the practical—the establishment of a minimum set of facilities that could serve national needs and the financial support to keep them run­ning—to the visionary—continued investment in CFD and focus on the challenge of hypersonic air-breathing research.

RAND analysts had concluded in 2004 that NASA’s wind tunnel facilities continued to be important to continued American competitiveness in the military, commercial, and space sectors of the world aerospace industry while "management issues” were "creating real risks.” NASA needed a clear aeronautics test technology vision based on the idea of a national test facility plan that identified and maintained a minimum set of facilities.

For RAND, the bottom line was the establishment of shared financial support that kept NASA’s underutilized but essential facilities from crumbling into ruin.[638] Anton found the alterna­tive—the use of foreign tunnels, a practice many of the leading

aerospace manufacturers embraced—problematic because of the myriad of security, access, and availability challenges.[639]

NASA’s wind tunnel heritage and the Agency’s viability in the inter­national aerospace community came to a head in 2009. Those issues centered on the planned demolition of the most famous, recognizable, and oldest operating research facility at Langley, the 30- by 60-Foot Tunnel, in 2009 or 2010. Better known by its NACA name, the Full-Scale Tunnel was, according to many, "old, inefficient and not designed for the computer age” in 2009.[640] The Deputy of NASA’s Aeronautics Test Program, Tim Marshall, explained that the Agency decided "to focus its abilities on things that are strategically more important to the nation.” NASA’s focus was supersonic and hypersonic research that required smaller, faster tunnels for experiments on new technologies such as scramjets, not subsonic testing. In the case of the last operator of the FST, Old Dominion University, it had an important mission, refining the aerodynamics of motor trucks at a time of high fuel prices. It was told that economics, NASA’s strategic mission, and the desire of the Agency’s landlord, the U. S. Air Force, to regain the land, even if only for a park­ing lot in a flood zone, overrode its desire to continue using the FST for landlocked aerodynamic research.[641]

In conclusion, wind tunnels have been a central element in the success of NACA and NASA research throughout the century of flight. They are the physical representation of the rich and dynamic legacy of the organization. Their evolution, shaped by the innovative minds at Langley, Ames, and Glenn, paralleled the continual development of aircraft and spacecraft as national, economic, and technological missions shaped both. As newer, smaller, and cheaper digital technologies emerged in the late 20th century, wind tunnels and the testing methodologies pioneered in them still retained a place in the aerospace engineer’s toolbox, no matter how low-tech they appeared. What resulted was a richer fabric of opportunities and modes of research that continued to contribute to the future of flight.

In support of the Apollo lunar landing program, engineers at the Langley Research Center had constructed a huge steel A-frame gantry structure, the Lunar Landing Research Facility (LLRF). Longer than a football field and nearly half as high as the Washington Monument, this facility proved less useful for its intended purposes than free-flight jet-and-rocket powered training vehicles tested and flown at Edwards and Houston. In serendipitous fashion, however, it proved of tremendous value for aviation safety after having been resurrected as a crash-impact test facility, the Impact Dynamics Research Facility (IDRF) in 1974, coincident with the conclusion of the Apollo program.[851]

Over its first three decades, the IDRF was used to conduct 41 full – scale crash tests of GA aircraft and approximately 125 other impact tests of helicopters and aircraft components. The IDRF could pendulum-sling aircraft and components into the ground at precise impact angles and velocities, simulating the dynamic conditions of a full-scale accident

or impact.[852] In the first 10 years of its existence, the IDRF served as the focal point for a joint NASA-FAA-GA industry study to improve the crashworthiness of light aircraft. It was a case of making the best of a bad situation: a flood had rendered a sizeable portion of Piper’s single – and-twin-engine GA production at its Lock Haven, PA, plant unfit for sale and service.[853] Rather than simply scrap the aircraft, NASA and Piper worked together to turn them to the benefit of the GA industry and user communities. A variety of Piper Aztecs, Cherokees, and Navajos, and later some Cessna 172s, some adorned with colorful names like "Born to Lose,” were instrumented, suspended from cable harnesses, and then "crashed” at various impact angles, attitudes, velocities, and sink-rates, and against hard and soft surfaces. To gain greater fidelity, some were accelerated during their drop by small solid-fuel rockets installed in their engine nacelles.[854]

Later tests, undertaken in 1995 as part of the Advanced General Aviation Transport Experiment (AGATE) study effort (discussed subse­quently), tested Beech Starship, Cirrus SR-20, Lear Fan 2100, and Lancair aircraft.[855] The rapid maturation of computerized analysis programs led to its swift adoption for crash impact research. In partnership with NASA, researchers at the Grumman Corporation Research Center developed DYCAST (DYnamic Crash Analysis of STructures) to analyze structural response during crashes. DYCAST, a finite element program, was quali­fied during extensive NASA testing for light aircraft component testing, including seat and fuselage section analysis, and then made available for broader aviation community use in 1987.[856] Application of computa­
tional methodologies to crash impact research expanded so greatly that by the early 1990s, NASA, in partnership with the University of Virginia Center for Computational Structures Technology, held a seminal work­shop on advances in the field.[857] Out of all of this testing came better understanding of the dynamics of an accident and the behavior of air­craft at and after impact, quantitative data applicable to the design of new and more survivable aircraft structures, better seats and restraint systems, comparative data on the relative merits of conventional ver­sus composite construction, and computational methodologies for ever­more precise and informed analysis of crashworthiness.