Moments & Milestones: The First “A” in NASA
- By GEORGE C. LARSON, MEMBER, NAA
- Air & Space magazine, November 2008
NASA Glenn Research Center
This October 1, NASA celebrates its 50th anniversary. To the public, “NASA” means Mercury, Gemini, Apollo, the shuttle—all things space. But of the agency’s half-century of research, some of its most dramatic advances have been in aeronautics.
NASA’s predecessor was the National Advisory Committee for Aeronautics. Today, the NACA is best known for the series of airfoils its engineers developed. Current jets, and even some light general aviation aircraft, fly on wings with airfoils designed not at the NACA but at NASA. The C-17 Globemaster III transport, for example, has what is called a supercritical wing, an airfoil developed at NASA in the 1960s. A supercritical wing makes jets more efficient by delaying the formation of drag-producing shock waves on the wing’s upper surface when aircraft near transonic speeds. With the upper curve of the airfoil flattened, the acceleration of air over the upper surface is reduced, and shock waves are prevented.
Another wing innovation the agency developed, dating back to the 1970s, is the winglet, which reduces drag by turning the vortex of air that forms at the wingtip into a force that actually adds a little thrust. It works like a boat’s sail tacking into the wind. Winglets have recently grown very popular. You’ll see them today on some airliners and business jets.
Both the supercritical wing and the winglet were the products of not just one agency but one engineer: Richard Whitcomb, at NASA’s Langley center in Virginia (and earlier, at the NACA).
Also in the 1970s, NASA operated a Boeing 737 as a flying laboratory, using it to develop numerous technologies and concepts, primarily for the airline industry. In four-dimensional navigation, for example, computing systems guide the airplane in three-dimensional space as well as the fourth dimension: time. In other words, you end up where you should, precisely when you should. The concept is particularly relevant today, as it enables aircraft to calculate flight paths that are the most fuel-efficient.
NASA-developed improvements can be found in engines too. Advanced combustors reduce pollutants like nitrogen oxides. And should a fan blade fracture and fly off, passengers are protected by tough containment structures. Another reason for air travelers to thank NASA.
And now that all sorts of aircraft are made not of aluminum but rather of tough composites, like Kevlar and carbon-fiber, you’ll be glad to know NASA has researched the materials for decades, and helped solved some major composite-related problems. For example, composite airframes face different challenges in lightning strikes. Composites are non-conductive, so if a composite aircraft is hit by lightning, the electricity will pursue a path of least resistance, burning the composite as it goes. NASA helped develop a solution: embedding metal in the composite. The metal disperses the lightning’s charge through the exterior skin, and away from fuel and instruments.
NASA helped industry to develop the standards for what we now call the glass cockpit—electronic screens that have replaced electromechanical instruments and their thousands of delicate parts. Pilots now peer at a world that is more intuitive than the old one.