Aeronautics Under NASA

By Edward Goldstein

Test pilots Scott Crossfield, Maj. Robert White, USAF, and Neil Armstrong with the first and second X-15s. This photo was taken on the occasion of North American Aviation’s delivery of the second X-15 to NASA.

NASA PHOTO

On Oct. 1, 1958, NASA, an agency required by its founding legislation to pursue both aeronautical and space activities, officially opened for business with five facilities inherited from the National Advisory Committee for Aeronautics (NACA): Lewis Research Center in Ohio, Langley Research Center and the Wallops rocket test range in Virginia, and Ames Research Center and the Muroc aircraft test range in California. By executive order, President Dwight D. Eisenhower transferred existing space projects from other government agencies to NASA. NASA began with a staff of 8,240 (8,000 from the NACA) and a budget of approximately $340 million.

If there were any doubts in the public’s mind about where the fledgling agency was headed, they were eliminated six days later when NASA officials announced Project Mercury, the attempt to put a human in orbit. By April 9 of the following year, NASA introduced its first class of astronauts, and the space race was on. But while astronaut Alan Shepard’s first suborbital flight was still two years in the distance, North American Aviation test pilot Scott Crossfield was only two months away from the maiden flight of the X-15, the joint NASA-Air Force-Navy project to demonstrate experimental high-speed rocket-powered high-altitude aircraft. The long and cylindrical X-15 was conceived in 1952 as part of the NACA’s experimental aircraft program. The world’s first hypersonic research aircraft was carried into the atmosphere on a NASA B-52 that lifted off from Edwards Air Force Base, California, on Sept. 17, 1959, for the X-15’s first powered flight. Dropped from under the wing of the B-52, Crossfield engaged the X-15’s powerful Reaction Motors XLR11 engines and flew above 52,000 feet and beyond Mach 2 before he landed at Rogers Dry Lake, where the first Space Shuttles also ended their flights 22 years later. For nine years, the three X-15s flew 199 times, seven of them with Neil Armstrong in the cockpit, setting records for speed (4,520 mph, or Mach 6.7) and altitude (354,200 feet or 67 miles), often reaching the edge of outer space and returning with valuable data on aerodynamic heating, high-temperature materials, reaction controls, and space suits. Although the X-15’s flights did receive a due amount of publicity and honors, including the 1961 Collier Trophy for test pilots Maj. Robert White (USAF), Joseph Walker (NASA), Forrest Petersen (USN), and Scott Crossfield, news coverage paled in comparison to the live network broadcasts accorded to every human spaceflight of that era. Going forward, the story of aeronautics throughout NASA’s existence has largely been the same. Somewhat out of sight, but definitely not out of relevance.

The Spirit of Innovation Continues

Despite the lack of high-level attention and funding – NASA’s aeronautics function is proposed by the administration for $634 million in FY 2019 funding, or 3 percent of the agency’s funding – the results of NASA aeronautics research can be found in practically every domestically produced commercial transport or military aircraft flown today, making the skies safer, more efficient, and more environmentally friendly. NASA’s research has also greatly influenced the development of modern rotorcraft, unmanned aircraft systems, and our national air traffic management system. “Aviation as we know it today worldwide would not have the capabilities that it has, had it not been for the NACA/NASA investment in aeronautics,” said noted aerospace historian Dr. Richard Hallion. “I would stress that continuum, one to another. And the fact that you will rarely meet people as dedicated as those that have worked for NASA in this field. When you look at the challenges they faced, it’s extraordinary what they accomplished.” Indeed, aeronautics is often called the “quiet A” in NASA, but sometimes actions speak louder than words.

North American Aviation test pilot Scott Crossfield climbs into the cockpit of an X-15 after it has been jacked up to be mounted beneath the wing of NASA’s NB- 52B mother ship.

NASA PHOTOS

Changing Research Themes

While there certainly was continuity between the NACA’s and NASA’s dedication to conducting and building upon research into the fundamental problems of aeronautics, there are definitely themes that are unique to aeronautics research during the NASA period. One was the recognition that aviation was becoming a mature form of transportation in the latter part of the 20th century, and that research focused on discrete matters such as improving aviation safety margins, taking advantage of computers and composite materials to improve aircraft performance, and looking at ways to improve engine efficiency and to incorporate alternative jet fuels to reduce aviation’s environmental footprint would reap significant benefits. “As the technologies matured significantly, there were incremental things to take on that NASA took on and did so very effectively,” said Roger Launius, the associate director of collections and curatorial affairs at the Smithsonian’s National Air and Space Museum and former NASA historian. “I’m very much enamored with small projects that yielded major results, like the wind shear project that Langley did in the 1980s that yielded the warning system that’s on every airplane now for wind shear.”

The X-15-1 released from the NB- 52A carrier aircraft on May 12, 1960, with NASA test pilot Joe Walker at the controls. The flight reached Mach 3.19 and an altitude of 77,382 feet.

NASA PHOTOS

Another theme related to aviation’s advances was NASA’s focus, or lack of focus, on supersonic (Mach 1.25-5) and hypersonic research (Mach 5 and above). Decisions made in this research area were heavily influenced by the large expense of high-speed flight. For instance, during the 1960s, when NASA was aiming toward the Moon, the agency rejected taking a lead role in conducting research and development on a proposed American Super Sonic Transport (SST) airplane to compete with the French-British Concorde Consortium and the Russians (TU-144). Deputy Administrator Hugh Dryden wisely argued that, with Apollo underway,

NASA research pilot Milt Thompson sits in the M2-F2 “heavyweight” lifting body research vehicle before a 1966 test flight. The M2-F2 and the other lifting-body designs were all attached to a wing pylon on NASA’s B-52 mothership and carried aloft. The vehicles were then drop-launched and, at the end of their flights, glided back to wheeled landings on the dry lake or runway at Edwards AFB. The lifting body designs influenced the design of the Space Shuttle and were also reincarnated in the design of the X-38 in the 1990s.

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NASA didn’t have sufficient resources and managerial personnel to take on this massive and ultimately controversial project. But NASA never totally abandoned supersonic research. Today, “Innovation in Commercial Supersonic Aircraft” is one of six research thrusts defined in the agency’s “Aeronautics Research Strategic Implementation Plan,” with flight tests collecting data on the perceptions of sonic booms on the ground being one element of the research. In the area of hypersonic research, following the X-15 program, budget tightening and a lack of technological maturity affected programs such as the National Aerospace Plane, X-33 suborbital space plane, and X-38 wingless lifting body. Despite all the fits and starts with hypersonics research, Hallion believes that “NASA contributed greatly to the technology of high speed flight in terms of its studies of shapes, configurations, materials, guidance and control issues and pilot protection. That was tremendously useful.”

The M2-F1 lifting body is seen here under tow at the Dryden Flight Research Center (later redesignated the Armstrong Flight Research Center), Edwards, California. The wingless, lifting body aircraft design was initially conceived as a means of landing an aircraft horizontally after atmospheric re-entry. The absence of wings would make the extreme heat of re-entry less damaging to the vehicle. In 1962, Dryden management approved a program to build a lightweight, unpowered lifting body as a prototype to flight test the wingless concept. It would look like a “flying bathtub,” and was designated the M2-F1, the “M” referring to “manned” and “F” referring to “flight” version. It featured a plywood shell placed over a tubular steel frame crafted at Dryden. Construction was completed in 1963. The first flight tests of the M2-F1 were over Rogers Dry Lake at the end of a tow rope attached to a hopped-up Pontiac convertible driven at speeds of up to about 120 mph. These initial tests produced enough flight data about the M2-F1 to proceed with flights behind a NASA C-47 tow plane at greater altitudes. The C-47 took the craft to an altitude of 12,000 feet where free flights back to Rogers Dry Lake began.

NASA PHOTOS

A final theme related to aeronautics during the NASA period was how NASA’s approach to managing large-scale mission-oriented research forced the aeronautics component of the agency to alter its way of doing business. As Robert G. Ferguson points out in NASA’s First A: Aeronautics from 1958 to 2008, “Over time, the original intention to maintain a sharp distinction between an operational space program and basic research began to give way to a belief that all of NASA should be run in the same fashion as the space program,” he wrote. “In the NASA era, knowledge production gave way to the completion of big projects. The size of research expanded, and, increasingly, it involved teams of researchers working in conjunction with subcontractors. With big projects came big money and big management. This was in marked contrast to the lone researcher working on a topic of personal interest on bootstrapped wind tunnel time.” Of course the downside of this approach was that large aeronautics projects had to compete with the more amply funded space projects, and in many cases, the funding was not always there.

This photo shows the HL-10 in flight, turning to line up with lakebed runway 18. The pilot for this flight, the 29th of the HL-10 series, was Bill Dana. The HL-10 reached a peak altitude of 64,590 feet and a top speed of Mach 1.59 on this particular flight.

NASA/DRYDEN FLIGHT RESEARCH CENTER PHOTO

Enter the Lifting Body

That said, one of the agency’s most inventive aeronautical research efforts of the 1960s and 1970s, NASA’s Lifting Body Vehicles Research Program, was the opposite of a large project in its origins. It was largely driven from the ground up by enthusiastic engineers such as R. Dale Reed at the Flight Research Center (now Armstrong Research Center) in California. Using the motto, “Don’t be rescued from outer space – fly back in style,” Reed and his colleagues pushed for wingless lifting body designs first conceptualized at the Ames Aeronautical Laboratory – utilizing air flowing over a fuselage to generate lift – that would enable a spacecraft to fly through the atmosphere to a controlled landing on an airstrip rather than parachute back to an ocean splashdown, as was the case during the Mercury, Gemini, and Apollo programs.

Encouraged by Reed’s passion, Center Director Paul Bikle approved discretionary funding to construct a homebuilt lifting body featuring a plywood shell placed over a tubular steel frame, the M2-F1. Using volunteer help from center personnel, Reed built the M2-F1 for the princely sum of $30,000. Because the M2-F1 was unpowered, it was first tested at Rogers Dry Lake Bed by being towed around by a hopped-up 1963 Pontiac convertible speeding at 120 mph. It later attained free flight and had 77 air-towed flights. The larger M2-F2 and subsequent manned lifting bodies, the HL-10, X-24A, M2-F3, and the X-24B, contributed to the design and construction parameters of the Space Shuttles, although the actual shuttle design rejected the lifting body concept.

NASA selected a Vought F-8 Crusader as the testbed aircraft (designated TF-8A) to install an experimental Supercritical Wing (SCW) in place of the conventional wing. The unique design of the SCW reduces the effect of shock waves on the upper surface near Mach 1, which reduces drag. In the decades since the F-8 SCW testbed flew, the use of such airfoils on airliners has become common.

NASA PHOTO

The Genius of Richard Whitcomb

Original configuration of the NASA Boeing 737 with monochrome flight displays. This first “glass cockpit” paved the way for the full-color, multifunction electronic flat panel displays that equip aircraft flight decks today.

NASA PHOTOS

The NASA aeronautics story is also a legacy story of brilliant engineers who began their careers at the NACA and contributed greatly to modern aeronautics in the shadow of the space program. One person affected by the demise of NASA’s SST work was research engineer Richard Whitcomb, already celebrated for developing the Transonic Area Rule. “When he got out of the SST program, he threw up his hands and said, ‘It’s not going to happen,’” said colleague Joseph Chambers, who ran Langley’s Large Scale Wind Tunnel next door to Whitcomb’s 8-foot Wind Tunnel. “He went back to subsonic transport, trying to increase the speed capability of aircraft, which led to supercritical wing [a swept-back wing airfoil that delayed the onset of aerodynamic drag].” NASA tests of a supercritical wing design on the Vought F-8A Crusader aircraft in 1971 confirmed measurements from Whitcomb’s wind tunnel tests, which showed increased cruising speed, improved fuel efficiency and greater flight range than conventional-wing aircraft. This research led to the design being utilized on new airliners and business jets to reduce fuel costs and lower operational costs. Later in the decade, Whitcomb developed the winglet, a barrier at the tip of a wing in the form of a supplementary vertical wing that has improved aircraft efficiency by reducing another source of drag. The winglet technology was initially used for business jets, and has since been incorporated into most modern commercial and military transport jets. Aviation Partners Boeing (APB), the company that manufactures and retrofits winglets for commercial airliners, projects its Blended Winglet technology will have saved 10 billion gallons of jet fuel worldwide through the end of 2019. “If you take a look at Whitcomb as a focal figure, really the airplane today reflects his shaping genius about the way we approach aircraft design,” noted Hallion. “That was rooted very much in the NACA, but he was very effective at securing support in the Langley environment and continuing support through the NASA era.”

Results that Matter

F-8 Digital Fly-By-Wire aircraft in flight. The computer-controlled flight systems pioneered by the F-8 DFBW created a revolution in aircraft design. The F-117A, X-29, X-31, and many other aircraft have relied on computers to make them flyable. Built with inherent instabilities to make them more maneuverable, they would be impossible for human pilots to fly if the computers failed or received incorrect data.

NASA PHOTOS

In May 1970, NASA announced Neil Armstrong’s appointment as deputy associate administrator for aeronautics for the Office of Advanced Research and Technology. Although Armstrong, ill suited for a bureaucratic management position, would only last in that post for a year, NASA’s aeronautics function started to climb in importance within the agency, because it continued to produce results that mattered, and because the White House, Congress, and other stakeholders wanted to see more balance in the NASA portfolio of activities following the end of the Apollo era. The breadth and depth of NASA aeronautics innovations from the 1970s on are truly impressive:

• The development of the NASTRAN integrated software package, which became the standard structural analysis code for the aviation industry.

• Flight Research Center engineers validated digital fly-bywire aircraft, or all-electronic flight control systems. Digital fly-by-wire systems allowed computers to control military and commercial aircraft and the Space Shuttles, increasing stability and maneuverability.

• Spurred on by Ames Research Center Director Hans Mark, researchers at Ames as well as Langley revolutionized the use of Computational Fluid Dynamics, utilizing high-speed supercomputers that could solve demanding aeronautical research problems by using many processors in parallel.

• As transport aircraft instrument design increased in complexity, engineers at Langley joined with industry to develop and test electronic flight display concepts, culminating in test flights on a Boeing 737 using Rockwell Collins hardware that became the modern full-color, multifunction, electronic flat panel display glass cockpit. The technology went on to be standard equipment for commercial, business, and military aircraft and the Space Shuttle.

• A push to make airplanes more efficient in response to the 1973-1974 oil embargo imposed on the U.S. and other Western countries by the Organization of the Petroleum Exporting Countries (OPEC) and subsequent high jet fuel prices. NASA’s Aircraft Energy Efficiency Program expanded research on: Engine Component Improvement, Fuel Conservative Engines, Fuel Conservative Transport (aerodynamic design, active controls) Turboprops, 1 Laminar Flow Control and Composite Primary Structures. NASA’s work to make airplanes more fuel efficient and to reduce their carbon footprint continues today under its Environmentally Responsible Aviation program. The program has the goal by 2025 of reducing aircraft drag by 8 percent; aircraft weight by 10 percent; engine specific fuel consumption by 15 percent; oxides of nitrogen emissions of the engine by 75 percent, and aircraft noise by one-eighth compared with current standards.

• Following several high profile airline crashes involving wind shear, or dangerously strong downdrafts of wind currents affecting planes during takeoff and landing, Langley engineers teamed up with the Federal Aviation Administration to develop sensors to alert pilots of the imminent approach of hazardous weather.

• A joint Army-NASA project on tilt-rotor research aircraft culminated in flights at NASA/Dryden of the Bell XV-15, the first tilting-rotor vehicle to solve the problems of “prop whirl.” Its success directly led to development of the U.S. Marine Corps and U.S. Air Force V-22 Osprey.

• Thirty years before unmanned aircraft systems, or drones, became all the rage, NASA’s Highly Maneuverable Aircraft Technology (HiMAT) demonstrated the viability of pilotless, radio-controlled aircraft. Composed of various metal alloys, graphite composites, and glass fiber materials, and with sharply swept wings, winglets, and canard surfaces, HiMAT also pointed the way to the high-performance military aircraft that would eventually contribute to U.S. air dominance in modern conflicts.

• In the 1990s, NASA engineers at Ames, Langley and Lewis developed a computer-assisted engine control system that enabled a pilot to land a plane safely when its normal control surfaces are disabled. The Propulsion-Controlled Aircraft system uses standard autopilot controls already present in the cockpit, together with new programming in the aircraft’s flight control computers.

• In response to a 1994 crash of a commuter aircraft caused by severe icing conditions, NASA Glenn developed a cooperative icing flight research program with the FAA, the National Center for Atmospheric Research, and the Atmospheric Environmental Service of Canada. Ninety research flights focused on Supercooled Large Droplets, resulting in improved instrumentation and icing weather models, giving pilots a better chance to avoid this phenomenon.

Today, NASA’s NextGen contributions include the development of advanced automation tools to provide controllers with more accurate predictions about the nation’s air traffic flow, weather and routing.

A possible future hybrid wing body or blended wing body aircraft. The aerodynamics of such a design hold great promise for dramatic reductions in fuel consumption, noise and emissions. This concept also would use two wing-tip-mounted gas-turbine-driven superconducting electric generators to provide power to drive the electric fans propelling the aircraft.

NASA PHOTOS

An artist’s conception of NASA’s Low Boom Supersonic Demonstrator aircraft. The program’s goals are to design and build a piloted, large-scale supersonic X-plane to lower the effects of a sonic boom; and to fly the aircraft over certain U.S. communities to study human responses to the low-boom flights.

NASA PHOTOS

The NASA Aeronautics Research Mission Directorate (ARMD) is led by Dr. Jaiwon Shin, a South Korean-born expert in aerodynamics and heat transfer. Under the present project structure, ARMD is seeking to achieve a strategic vision that builds upon current U.S. aerospace leadership and enables revolutionary advances. The structure is based on six strategic thrusts: 1) Safe, Efficient Growth in Global Operations (NextGen technologies); 2) Innovation in Commercial Supersonic Aircraft; 3) Ultra-Efficient Commercial Vehicles (breakthrough technology for leaps in efficiency and environmental performance); 4) Transition to Low-Carbon Propulsion (alternative fuels and low-carbon propulsion technology); 5) Real Time System-Wide Safety Assurance; and 6) Assured Autonomy for Aviation Transformation (high impact aviation autonomy applications). These goals will be advanced by mission programs, including: Airspace Operations and Safety (e.g. Airspace Technology Demonstrations; Air Traffic Management- Exploration, System-Wide Safety, and UAS Traffic Management); Advanced Air Vehicles (e.g., Advanced Air Transport Technology, Revolutionary Vertical Lift, Commercial Supersonic, Advanced Composites, Aerosciences Evaluation and Test); Integrated Aviation Systems (e.g., Low Boom Flight Demonstrator, UAS Integration into the National Airspace System, Flight Demonstrations and Capabilities); and Transformative Aeronautics Concepts (e.g., Transformational Tools and Technologies, Convergent Aeronautics Solutions).

Tower controllers test out NASA surface automation tools in a simulation at NASA’s Future Flight Central air traffic control tower simulator. NASA researchers have developed a number of decision-support tools for air traffic controllers and aircraft crewmembers in order to make air travel safer and more efficient now and in the future.

NASA PHOTO

What all this adds up to, according to Shin, is a determination that if the agency is the “world premier R&D organization, we will be leading all the technologies in aeronautics for the world.” Shin added, “In my view, our country is asking us to put ourselves 10, 20 years ahead of U.S. industry and work on revolutionary, fundamental research. At the moment, at the present time, industry may not even realize that they actually need these certain technologies, or they cannot foresee the certain technologies needed for their market or product. We are responsible for having this vision that would put us way, way ahead of industry, and we will continue to work on achieving that. I believe that is our role and that is our mission, to stay ahead of everybody else in the world and continue to push the envelope of aeronautics technologies.”