Thanks to advancements developed by NASA, today’s aviation industry is better equipped than ever to safely and efficiently transport passengers to their destinations. In fact, every U.S. aircraft and air traffic control tower uses NASA-developed technology. Streamlined aircraft bodies, quieter jet engines, drag-reducing winglets, and lightweight composite structures are an everyday part of flying thanks to NASA research that traces its origins back to the earliest days of aviation. But NASA isn’t finished. Here are some new technologies that could change the airline industry of the future.
In-Flight Folding Wing
NASA is exploring the feasibility of a system that will allow part of an aircraft’s wing to fold in flight to increase efficiency through wing adaptation. Armstrong Flight Research Center, Langley Research Center, and Glenn Research Center are working on the Spanwise Adaptive Wing concept (SAW) that would permit the outboard portions of the wings to move as much as 75 degrees to the optimal position during flight. This could potentially result in an increase in efficiency by reducing drag and increasing lift and performance. A mechanical joint, acting as a hinge line for rotation, makes the freedom of movement possible.
Folding-wing capabilities have been around for decades, but have generally been used to conserve deck space on aircraft carriers and aircraft storage areas. While the XB-70 Valkyrie examined wing articulation 50 years ago, modern actuator technology makes it possible to explore deeper into its potential benefits.
“We are revisiting folding-wing aircraft because new technologies that did not exist in the 1960s allow actuation to be put in tighter wings, in smaller volumes,” said Matt Moholt, Armstrong’s principal investigator for SAW. “Now you can articulate a very small, thin air foil, whereas before, the actuator technology didn’t exist.”
The increase in the size of aircraft, including the integration of higheraspect- ratio wings, has made wing articulation more practical in areas of heavy aircraft ground operation. NASA seeks to examine the feasibility of unlocking further benefits from the technology by applying it to flight. This testing is made possible through the use of advanced actuators.
“Some wings are so long that to clear infrastructure, it has to fold on the ground. If we’re going to be articulating wings, let’s explore the use of an advanced actuator that could enable it to articulate in flight as well, then you can really put the wing in an ideal setting,” said Moholt. “Further, why just take the ground benefit of it? Let’s see if there’s a flight benefit of it as well.”
Advanced actuation could make possible a design that is both compact and lightweight, minimizing stress on the wing, and allowing for more compact packaging. Conventional systems have included gearboxes and hydraulic, pneumatic, or magnetic motors. NASA engineers believe actuator technology may be dramatically reduced in size and weight. Additionally, these solid-state actuators can be driven by an all-electric mechanism.
“In supersonic flight, yaw stability becomes a big issue,” said Moholt. “If you’re flying supersonically, you have tons of lift. Let’s say you need more yaw control. If I fold the wing portion all the way down, I may be able to trade lift in favor of more yaw control where I need it, and less lift where I don’t need it.”
NASA is working to create experimental aircraft that will demonstrate new green aviation technology intended to dramatically reduce fuel use, emissions, and noise — with the goal of cutting emissions from the nation’s commercial aircraft fleet by more than 50 percent while also reducing perceived noise levels near airports to one-half the level of the quietest aircraft flying today.
NASA experiments designed to help reduce fuel consumption and emissions flew on a specially outfitted Boeing 757 airplane called the ecoDemonstrator. The first experiment is the Active Flow Control Enhanced Vertical Tail Flight Experiment. NASA worked with Boeing to install 31 tiny jets called sweeping jet actuators that can manipulate, on demand, the air that flows over the ecoDemonstrator 757’s vertical tail and rudder surfaces. An aircraft’s vertical tail is primarily used to add stability and directional control during takeoff and landing, especially in the event of an engine failure. But when the aircraft is cruising at altitude, the same large, heavy tail is not necessary. Engineers theorized they could reduce the size of the vertical tail by using the sweeping jets to generate the same side force during takeoff and landing that a larger tail does. That would reduce the weight and drag of the airplane and decrease its fuel consumption.
Ground studies by NASA, Boeing, University of Arizona, and Caltech researchers on a full-scale 757 vertical tail in a wind tunnel showed the active flow control jets could increase side force by 20 to 30 percent, which could allow designers to scale down the vertical tail by about 17 percent, and reduce fuel usage by as much as one-half percent.
The agency’s other green aviation initiatives include reducing airline emissions and flight delays. Working in partnership with airlines and air traffic controllers at the Charlotte Douglas International Airport in North Carolina, NASA is beginning the first-of-a-kind demonstration of new technologies that coordinate operational schedules for aircraft arrivals, departures, and taxiing.
Pilot Training and Cockpit Displays
Engineers at Langley Research Center are looking at ways to improve flight training, cockpit displays, and other flight deck operations. As a result of a collaboration with American Airlines, they will have the chance to fly as observers in the cockpit during at least a half-dozen round-trip American flights each year to get firsthand knowledge of flight crew actions and reactions.
NASA Langley aviation safety research is helping to improve flight simulator realism following studies by engineers of loss-of-control events, where planes ended up in unsafe orientations or other conditions, such as aerodynamic stall, that sometimes resulted in accidents.
“By partnering with Langley, American can incorporate higher simulator fidelity and provide more realism in our flight training,” said American Airlines Captain Dan Kiggins. “Making scenarios that are more challenging and more fluid provides a richer training experience for pilots, which ultimately is to the benefit for our passengers.”
Part of the collaboration includes American participation in NASA testing, such as providing professional pilots. Langley also has flight simulators it uses to develop new cockpit technologies and procedures aimed at making flights safer and more efficient.
NASA has a number of agreements with different airlines to help further its research. A Langley association with American — and pilot Kiggins in particular — goes back more than 15 years. Kiggins was one of a half-dozen pilots who not only tested NASA “synthetic vision” technology in simulators, but also assessed the cockpit display while flying a NASA research aircraft in Colorado in 2001.
Synthetic vision systems, which are now available commercially in part because of NASA aviation safety research and collaborations with industry, are display technologies that offer pilots an electronic picture of what’s outside their windows, no matter the weather or time of day. Langley is continuing research into improved vision displays for flight crews. Researchers are also studying workload issues, enhanced training capabilities, and new technologies to help pilots better understand how a plane is behaving.