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MIT Designs Aircraft That Uses 70% Less Fuel Than Conventional Planes
greenrainbow writes "Today a team of researchers at MIT unveiled their design for an airplane that uses 70% less fuel than conventional aircraft. The MIT design comes thanks to a NASA-funded initiative to increase fuel efficiency, lower emissions, and allow planes to take off on shorter runways. The team accomplished all of NASA's set goals with their innovative D-series plane, lovingly referred to as the 'double bubble,' which has thinner, longer wings and a smaller tail, and engine placement at the rear of the plane instead of on the wings."
Looks like it's fuselage is also a lifting body.
I wonder how the seating configurations are for these planes. There is no scale provided so you wonder what they are calculating on, is it fuel per mile per passenger? Anything else would be irrelevant.
One way they save fuel: flying slower than current aircraft. First, will customers accept that? And second, why not just fly current 737s a bit slower right now, to save on fuel?
NASA's link says the 777 design flies 10% slower. A pretty good return!
Arguing with an engineer is like wrestling a pig in the mud. After a while, you realize the engineer enjoys it.
I remember watching a documentary on the new Airbus plane. There are regulations on wing length, and that plane *has* to use the perpendicular tips at the end of its wings to help with lift, or its wings would be too long. If you require longer wings per pound, you will fit less passengers per plane to fit in regulation. They will have to find a way to collapse the wings without adding significant weight or complications to make this practical for larger planes. That is a very big hurdle, maybe they should focus on that next.
I can't remember why, but I remember them stating that the wing length regulations had very good reasons behind them (logistics of current airports being a major one if I recall). I don't think changing the regulations would be practical if that was the case.
Having a viable prototype design that's gone through simulations and the like is a lot more than artists renderings. What the hell do you think they do to make an airplane? Take some steel, rivets, and aluminum out to the hangar and just see where things end up?
"People who think they know everything are very annoying to those of us who do."-Mark Twain
Well, that and a bottle of jack daniel's, yeah...
It's actually two cylindical (or semi-cylindrical) cabins joined together lengthwise, with a stressed interior partition framework. Kinda like a number 8 laying on its side. Pressurization isn't difficult in that case, and the interior stressed partition can be a latticework. It's not a new idea, although it's never been done for reasons of practicality, just a lot simpler to make the body a long tapered tube and be done.
I'm disappointed in both of the linked articles. Some real substance about the design would have been nice, but as it is, I'm left with a lot of questions:
-70% less fuel? How much of that is aerodynamic savings and how much of that is engine efficiency savings?
-Did they do any wind tunnel testing of their model? How close were their CFD and tunnel test results?
-Are they using engines based closely off existing ones, or are they projecting fuel savings 25 years into the future (the 2035 time frame from the article)?
-What sort of structural weight-saving advances are they assuming, or projecting from?
-So they made the tail smaller, what makes up for the reduction in control authority there?
-Plus other more detailed questions based on the answers to those questions. Would it have been so hard for MIT to link a design document pdf or something? I guess not being a public university, they don't have to if they don't want to. Too bad.
It's not impossible. I used to bullseye flow dynamic calculations on my Ti-15 back home, they're not much bigger than two OOM.
The type D is specifically designed to work with existing airports without drastically changing the terminals.
The type H, however, would require changes to current airports. The article says that these designs are planed for a 2035 deployment, though, so plenty of time to make the requisite changes, if the airlines so chose.
It took FOREVER to get a composite commercial aircraft into production because the insurance companies had no data on hull integrity to do the underwriting. As a result, the proposed premiums were based on utter disaster.
It may have been the Beech Starship http://www.wingsoverkansas.com/legacy/article.asp?id=775 that provided some useful data. Although a turboprop, it is pressurized, and the more-frequent pressure cycling of a corporate hauler may have given them some idea that composites aren't highly more likely than conventional aluminum hulls to become convertibles (Aloha 737) in flight.
If the US gov't really wanted to help advance the aircraft industry, they'd create an insurance agency for new designs and materials.
the design mitigates some of the drawbacks of the BLI technique by traveling about 10 percent slower than a 737.
I wonder if they accounted for the added weight of beefing up the trailing edge of the wing to withstand bird strikes.
Never shake hands with a man you meet in a fertility clinic.
You know, people, it is perhaps shameful to admit in front of this audience but despite working at the cutting edge of technology I only shrug at news like this one. Instead of all the exiting engineering/scientific thoughts that most of you exhibited and made the discussion interesting the only thing that crossed my mind was something like:
"So, we are going to save 70% of the fuel. What would happen in such "vacuum" Well, we will just build 70% more plains, fly even more people around, cheaper perhaps so the "gain" in efficiency will be quickly drowned by the increased volume of planes and passengers. Move along, nothing to see here..."
I don't want to rain on anybody's parade but every time when some new technological development frees us time, it is immediately filled with more work, not more recreation or hobbies or family life. When it comes to food and water it is even worst. Just consider the "green revolution" from the 70's. Population pressure due to the baby boom after the war. Solution - industrial agriculture which completely kills the taste of food (especially fruits and vegetables) but its efficient and easier to transport and preserve. When it was all over , did we wipe out the noble sweat and sat down to enjoy the fruits of our ingenuity (pun intended)?
No, because the population pressure was already pushing us again. We will never catch up with this. And as every scientist will tell you , every next step will require more energy and more effort to squeeze maximum yield from minimum volume. Asymptotic approach to use the proper term. Like trying to accelerate a mass to the speed of light. As long as we do not stop the geometrical progression of our multiplication we will never be able (most of us) to enjoy what the progress is all about - giving MORE time for ourselves and our personal development and personal life. Giving MORE and higher quality goods and services per person (population flat, but efficiency increases).
Globally as humans we experience what we people in the west experience with the constant inflation - you have to run ever harder just to stand still. Miss one year's promotion or a raise and your buying power goes down. The effect of missing one year only is accumulative like compound interest. I am sick to the teeth that I have to run like a mouse on an endless tread just to stand still. Just to exists. And being told all the time how good I have it.