The next time you jet off on a cross-country vacation flight or a short-hop work trip, say a little thank you to NASA.
The agency is best known for, but it’s long been at the forefront of aviation as well. Every flight you take today is made possible through technologies NASA has developed, from the shape of your airplane’s wing to the air traffic control systems that guide your flight through the air. You may not be flying to the moon, but you are riding on NASA’s decades of aviation research.
The goal of NASA’s Aeronautics Research Mission Directorate: Make air travel better for everyone, not just military fighter pilots or astronauts in training.
“[Our] ambition is to help the US aerospace industry be at the leading edge of the global market,” says Peter Coen, project manager for NASA’s Commercial Supersonic Technology Project. “We’re putting the technology out there that essentially the aerospace business can use to make successful products.”
To get there, NASA conducts a huge range of research projects for the next generation of aircraft. Some of the models that have been in its wind tunnels don’t look like anything carrying passengers today — say, a blended-wing aircraft that combines the wing and fuselage into a single bulbous structure that looks like something you’d see sneaking a flight out of Area 51. But the agency isn’t confining itself to daring experimental designs or Jetsons-like dreams of personal airplanes for crowded cities. It’s also working on perfecting existing aircraft to make them safer, cleaner and much, much faster.
Before NASA and after
NASA’s history with flight goes back more than a century, starting with the National Advisory Committee for Aeronautics, founded in 1915. At what’s now NASA’s Langley Research Center, the NACA experimented with wing shapes, built early wind tunnels and helped develop the X-1, the first airplane to break the sound barrier.
When NASA was founded on Oct. 1, 1958, absorbing the NACA’s aviation research, the jet age and the era of mass air travel were just taking off. One of its first flight projects was the rocket-powered X-15 research aircraft, part of a long series of experimental X-planes that continues to this day. The X-15 set altitude and speed records, and data from the program was invaluable in helping astronauts handle spaceflight.
Later developments have trickled into every aspect of aviation today. Fuselages made of composite materials make airliners like the Boeing 787 and the Airbus A350 stronger and lighter, winglets save fuel by helping airplanes fly more efficiently, and synthetic vision systems let pilots fly more safely by giving them increased information about the environment around them.
NASA isn’t stopping there. Here are three programs it’s bringing to the skies.
In the nearly three decades that it carried passengers, the Concorde, the world’s only supersonic airliner to regularly carry them, delivered the fastest and most exclusive ride in the sky. But its engines were deafening on takeoff, it spewed emissions at high altitudes (about 56,000 feet), and it was massively expensive to operate. Regulations that limited or banned sonic booms over land also meant that it had few places to fly.
The Concorde was permanently grounded in 2003, but NASA is now working to help travelers like you break the sound barrier again. By softening the effects of a sonic boom, which can annoy people, disturb wildlife and damage structures, it hopes to persuade governments that faster-than-sound flight over land isn’t a bad thing.
“We want to get to the point where we essentially have supersonic airliners that could fly any route while being efficient and otherwise an environmental good neighbor,” Coen says.
In April, NASA announced a partnership with Lockheed Martin to build a test airplane with “low boom” technology, scheduled for a first flight in 2021. Both say the Low-Boom Flight Demonstrator (also known as the LBFD or the X-59 QueSST) will produce a sonic boom that sounds more like a car door slamming than the thunderous noise Concorde produced.
Key to dampening the boom is the LBFD’s shape. A long, pointed nose, sharply swept wings and raked canards (small wings positioned forward of the main wings) ensure that the individual shock waves the airplane produces at speeds faster than Mach 1 never converge and cause a traditional sonic boom.
“We’ve found the best way to reduce [a sonic boom] is to control the strength and position of each wave so that they’re relatively similar in strength, and relatively evenly distributed along the length of the airplane” Coen says. “If you do that, most of them don’t converge.”
Until the LBFD flies, NASA will conduct tests using one of its F/A-18 aircraft to see if a quieter boom is possible. During the tests, which begin in November, the F/A-18 will dive from almost 50,000 feet over the Gulf of Mexico off Galveston, Texas, and go briefly supersonic before leveling off at about 30,000 feet. The sonic boom produced from the dive should sound more like the LBFD’s predicted boom (NASA calls it a “sonic thump”).
After initial test flights to assess the LBFD’s general performance as an airplane, Lockheed and NASA will start flying it supersonically in 2022 over populated areas from California’s Edwards Air Force Base. These flights will have a twofold mission: Make sure the LBFD has a low boom and gauge public response to it. Coen says the hope is that residents won’t mind the noise overhead.
“We really want to get as broad a response as we can,” he says. “We want to understand what the effects of repeated exposures are as well as individual exposures.”
But if even the flights are successful, there’s still one big hurdle to ordinary people sipping supersonic champagne again. Since 1973, the FAA has prohibited commercial supersonic flight over the United States. Overturning that ban, and similar ones in other countries, is critical before supersonic flight can be economically viable.
“The aviation business is so global these days that any product built in any country is going to be certified in other countries in order to make it successful,” Coen says. “So [to go supersonic] you have to keep quiet.”
Noise concerns don’t afflict just supersonic aircraft. Sit under the final approach to the runway at any airport, and the whine of descending flights is unmistakable, sometimes painfully so.
Though jet engines rightly get most of the blame for aircraft noise, Mehdi Khorrami, an aerospace scientist at Langley, says an aircraft’s landing gear can be an even bigger factor. As an airplane comes in to land, air flowing over its extended landing gear causes turbulence, which translates to noise.
“The engine [sound] is still significant, but the airframe is really a prominent portion of the aircraft noise,” Khorrami says. “NASA has this long-term goal … to confine that objectionable part of the aircraft noise to within airport boundaries.”
One idea NASA’s developed is to put noise-absorbing foam into the well in the fuselage where the gear retracts during flight. It’s also developed fairings — plates that cover landing gear when extended — with tiny holes that allow air to pass through and reduce noise.
Then there are the surfaces on the wing that slow an aircraft during descent. When flaps are lowered on most existing aircraft, noise comes from air flowing in the gap between the flap and the wing’s back end. But with NASA’s experimental Adaptive Compliant Trailing Edge flap, there’s a seamless transition between it and the wing.
“These concepts will really reduce significantly the noise that is produced,” Khorrami says. “So when an an airplane lands, it would be no louder than the surrounding background noise. That’s a tall order.”
When developing noise-cutting technology, Khorrami starts by conducting computer simulations. That’s followed by deploying the technology on models in wind tunnel tests and then on a real aircraft as part of NASA’s Acoustic Research Measurement flights based at Edwards. As with the LBFD, microphones on the ground measure the noise level of the test Gulfstream III.
So far, Khorrami says, the landing gear and flap changes have reduced noise on the test aircraft by 70 percent. But his team also has to make sure its tech won’t hurt an aircraft’s flight performance and will allow air to cool its brakes when it’s on the ground.
“It has to be the right balance between significantly reducing the noise and not impacting [a plane’s] operation,” he says.
Even as it works on a quieter aircraft design, NASA isn’t ignoring engines. An electric-powered aircraft in development would be cleaner, quieter and more efficient.
Though the notion of an electric airplane may worry you — maximizing your battery’s range is a more pressing issue 35,000 feet in the air than on the freeway — it’s hardly a pie-in-the-sky idea. Besides NASA, others are pursuing the goal of an electric plane, including European low-cost airline Easyjet, which plans to fly one in 2021.
For its part, NASA is developing an all-electric test aircraft called the X-57 Maxwell using a modified Tecnam P2006T aircraft. Though much of the basic design is unchanged, NASA is replacing its gas-powered propellers with electric engines. Using an existing aircraft has a couple of advantages: NASA doesn’t have to design an entirely new plane, and it can compare how the electric-powered X-57 performs with how the airplane flew on its original engines.
The main goals of the project are to see a 500 percent increase in flight efficiency over a standard P2600T and to set standards for electric propulsion. Other benefits would include a reduction in carbon emissions and engine noise and lower operating and maintenance costs. In other words, they’re pretty much the same reasons you’d buy an electric car.
Though the project is aimed at private planes and air taxis for now (current battery technology has a range of around 50 miles), the technology could one day result in a turboelectric passenger airliner. Tom Rigney, project manager for X-57, says lower operating costs for such an aircraft may translate to lower airfares for passengers.
“Electric aircraft are more efficient, quieter and friendlier to the environment than standard fuel-powered aircraft,” Rigney said in an email. “Electric propulsion technologies may also allow smaller aircraft to take off and land vertically on roof tops or from parking lots, making them more accessible for applications such as air taxies and commuter aircraft.”
The tests will exist in four stages, starting from ground tests of the electric engines and ending with a fully modified X-57 taking to the air. That plane will have a long, experimental wing to give it more lift, two electric motors on the wingtips for propulsion and 12 smaller electric motors to give it more speed for takeoff. NASA also is training pilots in simulators to fly an electric plane and building an 860-pound lithium-ion battery to power the motors.
Sean Clarke, principal investigator for X-57, says some of the battery technology comes from designs NASA developed for the International Space Station.
“This helps ensure that failures in the battery system are contained and won’t impose an increased safety risk to the aircraft,” Clarke said in an email. “The X-57 Maxwell aircraft uses electric motors that are customized for the power and speed needed for this aircraft, but does not require development of new technologies.”
Taking It to Extremes: Mix insane situations — erupting volcanoes, nuclear meltdowns, 30-foot waves — with everyday tech. Here’s what happens.
Fight the Power: Take a look at who’s transforming the way we think about energy.