Newer engines perform most efficiently at relatively slow speeds, Drela says. Indeed, the "double bubble" is designed to fly about 8 percent slower than today's commercial airliners. But a wider body with two aisles could allow faster loading and unloading of passengers—meaning overall trip time could be less despite the flight speed, he says.
Flying hybrids
Research into biofuels promises to reduce fuel consumption and emissions with only marginal changes to planes that have remained basically unchanged for decades. Boeing's N+3 proposal focuses on a hybrid jet fuel–electric propulsion system. Such an engine could reduce fuel consumption by 70 to 90 percent compared with typical aircraft today, Boeing spokesman Daryl Stephenson says. Such a hybrid engine could be especially useful in shortening takeoff distances, he adds, providing extra kick as the vehicle goes airborne. During takeoff and climb, the aircraft would use both jet-fueled turbines and an electric drive to provide the needed power, says Marty Bradley, the Boeing engineer in charge of the subsonic design effort. While cruising, the plane would rely on either its gas turbines or electric drive.
Northrop Grumman's N+3 approach calls for a 120-passenger plane built from ceramic composites and "smart metals" that can deform and return to their original shapes. Although the aircraft resembles a conventional jet, it is designed to take off and land on runways 1,500 meters long, compared with 2,400 meters or longer for today's jets. Northrop is hoping this shorter runway space will enable these planes to be used at smaller regional airports, relieving some traffic from large international fields.
Changes on the horizon
NASA has much work ahead of it to coax big changes out of an industry that has maintained conventional approaches to engineering for so long. What's more, achieving the meaningful reductions in emissions would require that these ecofriendly changes be widespread across the entire aviation industry—not limited to one or two aircraft-makers.
In the short term the push to develop viable biofuels, which are said to be carbon-neutral, likely will dominate efforts to make commercial aviation easier on the environment. "Already three airlines have had successful trials with a mix of kerosene and various biofuels, such as Jatropha and camelina," and fuels based on algae also have shown promise, Green Aviation's Pozniak says. Europe is pushing biofuels over the next couple of decades through emissions trading rules that require airlines to pay for their carbon use, he adds.
And the most innovative aircraft redesigns are yet to come. The truly green plane of the future will run on solar energy, requiring no fossil fuels and generating zero emissions, Pozniak says. A group called the Solar Impulse project, led by the balloonist Bertrand Piccard, successfully tested its Solar Impulse HB-SIA, on a 26-hour voyage in Switzerland earlier this month.
"We are setting the bar rather high," says Jay Dryer, director of NASA's Fundamental Aeronautics Program Office, who is overseeing N+3. "We're really trying to push as many [advances] simultaneously as we can." Dryer doubts that one design will be able to meet all of the agency's targets. More likely, certain elements of the various proposals will appeal to manufacturers and eventually make their way into airplanes, he adds. Solar flight might be the most ecologically friendly technology, but Dryer predicts it will not be mature enough to ferry large numbers of passengers for a half century or more.
Subscription Center
Rights & Permissions
See what we're tweeting about
10 Comments
Add CommentFinally, NASA is thinking about doing something worthwhile. That does not mean it will do anything. NASA is a 50 year old organization with 50,000 permanent government employees, who have learned out to assure their bonuses and hire their friends. Contractors are used to do any real work. Most NASA employees (ok, there are some good scientists) are fixtures in a bureaucratic system that spends most of its energy to justify its existence. While this effort is good news (better than Lisa Nowak and her space soap opera, or the project to go back to the moon), it is unlikely NASA can produce anything. True innovation never comes from a 'permanent government employee', -it never did. Time to disband these corrupt people and shrink NASA down to a PR organization, -which is what it does best.
Reply | Report Abuse | Link to thisThat is fine but won't put a boot on Mars. This country works best when it has a funded long term goal.
Reply | Report Abuse | Link to thisWhat an absolute waste of taxpayer money. Boeing and Airbus will build airplanes that the market demands. If higher fuel prices are the "economic climate", then aircraft like the 787 get introduced. The work being done by NASA is virtually zero as compared with what industry is doing directly to research future technologies. With the US budget being how it is, government spending needs to be better focused and productive. (and I am an very senior aerospace engineer who has been in industry for 30 years)
Reply | Report Abuse | Link to thisSanoran, I believe Richard Whitcomb was a permanent NASA (and NACA) employee.
Reply | Report Abuse | Link to thisI agree with Sisko. As the price of oil increases, Boeing and Airbus will do an excellent job of creating new planes... and if the government wants to influence or help, -they can fund projects via NSF, DARPA etc, and have the Universities, like MIT, be involved.
Reply | Report Abuse | Link to thisNASA's corruption and inefficiency (permanent government employees have little motivation) makes it a waste of money to have NASA involved.
It'll be interesting to see what innovations NASA can come up with, writing contracts for $12.4M. The $125M redundant/competitive FAA program would seemingly have a better shot at producing something worthwhile, although neither project is likely to defray much of the $10B new jumbo jet model development costs.
Reply | Report Abuse | Link to thisThe FAA really thinks the passenger load on U.S. airlines will more than double in 20 years? I didn't see anything about VTOL mentioned - I wonder whose going to build the additional airport facilities? Perhaps the FAA and NASA should be funding more research into flight facilities, control and management.
The idea that NASA is, A) corrupt, and B) a waste of money is drivel. The idea that commercial outfits focused on the quarterly bottom line can or will do anything but incremental tweaking is rubbish.
Reply | Report Abuse | Link to thisTax dollars generate revenue to the nation at varying rates, and return tax dollars on the GNP created from the tax dollars spent. Taxes spent on warfare generate roughly 80 cents back on the dollar. Taxes spent by NIH and NSF generate, on average, between $2 and $3 for every dollar spent. These evaluations have to be done over a 20 year period (and that isn't long enough) because it takes so long for products to move into the pipeline. (For example, the idea of using windows on a computer screen took 16 years to come to market in a fast paced industry.)
NASA has returned between $7 and $8 for every tax dollar spent. Look around you. Almost everything has its roots in NASA. From the microprocessors that became the computer you use, to the skillet in your kitchen and most of your cell phone, it had its roots at NASA.
The problem NASA has now is that it doesn't have a big enough project or goal. This is because half-educated people who think they know it all have this idea that NASA and the space program were a waste of money. They don't bother checking facts, they just lay into the single most consistently high ROI tax expenditure the USA has ever made.
Fact is, if we want to crow our economy fast over the next 20 years, we should throw trillions at NASA and do something big like colonize Mars. That direct investment won't have direct payoff. But the technologies and methods that will spin off from it will pay for it many times over. There is nothing else we can spend tax dollars on that will do as much. NSF and NIH have good PR people, and yes, they are good, solid ROI tax expenditures. But they are roughly 1/4 to 1/3 the ROI of NASA.
And no, I don't work for NASA. I am a PhD microbiologist working in industry, who has been supported by NIH grants in the past.
Reply | Report Abuse | Link to thisI agree wih Dr Toradze. It would also be better if we in the developed world spent our money on manned space programs directed to self supporting settlements on Mars, and the moon in co-operation with other nations than spending it on wars of interference in other nations. Innovation in the aviation industry can come from many areas, but private industry cannot do it alone on projects of this scale. Industry usually reacts to existing conditions. The kind of lead time we need in large changes of technology that we need are an order of magnitude greater than they can provide. That is why NASA should be involved in the research to proof of concept vehicles stage of aviation development in co-operation with universities and industry in all countries.
Reply | Report Abuse | Link to thisjimfromcanada - Your sentiments are well intentioned, but if private industry invests billions of dollars to develop each major commercial aircraft model and NASA is spending a few million on aviation research, it can only be said that private industry is doing it on their own. Twelve million dollars likely only buys you a couple of conceptual design studies. Unless a larger undisclosed investment will be issued, I think there's not much substance to this report.
Reply | Report Abuse | Link to this