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Boeing Blended Wing Body Aircraft
pcolley writes "I love it when Science Fiction becomes reality. Boeing is nearly finished designing their super efficient Blended Wing Body (BWB) airplane. It looks like the BatJet." Boeing is considering both civilian and military roles.
There've been delta-wing type aircraft since the 50's. Always touting the "lift of the entire aircraft". What exactly is the issue that 1) they have never caught on with the airlines or public and 2) Boeing thinks it's solved? What am I missing?
7 November 2006: The day Americans realized corruption and incompetence weren't addressing 11 September 2001
I just hope that they have worked out the stability problems. The "all-wing" design has been notorious for being unstable except with computer help and "fly by wire" controls. If they have trumped these problems, go ahead; besides, I have no need to see outside the craft (one of the downsides mentioned. The passengers would be seated in wide rows only a few deep- think of the current tube and turn it 90 degrees, so only a few people would have window seats). But they are considering placing LCDs in front of all the seats with the option of seeing outside the plane. Now if they gave me ultra zoom over the midwest so I could see that farmer's daughter......
Vote monkeys into Congress. They are cheaper and more trustworthy.
The flying wing "blended wing body" (BWB) concept i was originally developed by McDonnell Douglas but was acquired by Boeing when the two companies merged.
Hooray for industry.
The theory of relativity doesn't work right in Arkansas.
The top down view reminds me A LOT of a stealh bomber.
"We've dropped off the passengers in France, now to drop off our 'packages' in northern Afganistan."
It's difficult to imagine anybody flying in this thing. For one thing, the passengers are intended to be kept in compartments close to the center of the aircraft, so no window seats. The very wide body means much greater displacement when the aircraft banks so even a slight bank would feel like a roller coaster ride for those on the extremities. One of the most important design challenges is emergency evacuation. And -- would the average person fly in a radically new, untested airframe?
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Boeing calculates that a BWB seating 480 passengers would use 32 percent less fuel than the proposed A380-700 [...] The plane would weigh 19 percent less, suggesting that it would cost less to build. And it would need 19 percent less thrust, saving on engine manufacturing and maintenance costs.
We at Boeing have the solution you are waiting for. Yes, our 747 is outdated and someone else is making a better product. We don't have an alternative to show but if you hold off buying your new big planes just another few years we'll supply you with a cheaper, better and more efficient product.
Now, why exactly does this all sound so terribly familiar to most of us?
I'm inclined to act on behalf of Jack Northrop, who was flying blended wing bodies in the 40's. I'm calling BULLSHIT! The N-1M is still a popular flying wing aircraft with private pilots today. The N-9M is equally popular with model aircraft enthusiasts (I personally spent two years of my youth finding a rare Tamiya kit of one of these). Then theres the B-35 which just barely missed WWII, but was featured in the original Orsen Wells "War of the Worlds" movie. Then there was the YB-49, a jet powered blended wing bomber. And lets not forget the MX324, Americas first rocket powered military aircraft (the designation "MX" is for "Missile, Experimental", which probably didn't comfort the pilot too much). Of course, the Nazi's had everyone beat with their ME-262 Komet - a rocket powered blended wing fighter-interceptor.
Boeing can no more claim this is "revolutionary" than I can claim that my G3 PowerPC powered linux server at work is revolutionary.
http://www.wpafb.af.mil/museum/fta/fta198.htm"
So how exactly does this benefit the consumer? How much do airlines currently spend on fuel? How much does one flight cost other than the fuel?
I suppose if fuel costs would be 1/3 less per person and the number of flights required per day would be cut in half, the savings per passenger would be somewhere in the 33% to 50% range, but how much of that are we likely to see?
The plane would weigh 19 percent less, suggesting that it would cost less to build. And it would need 19 percent less thrust, saving on engine manufacturing and maintenance costs.
Okay, now _that_ is cost analysis for you! By that reasoning a gun should cost less to build than a club because it weighs less. That example is a little oversimplified, but if the BWB was really similar enough to the tube and wing design to justify that kind of ballpark estimate then they wouldn't have needed to spend as much time researching as they have (and will continue to spend) to solve the engineering dificulties presented by the new design. And Boeing is going to have to factor in the costs of the long research period once they actually start producing it.
Last i checked the airlines weren't in great finacial shape, and once these things start rolling out of the factories they may have to start taking out large loans to update their fleets. And of course they're unlikely to drop the price on tickets by a huge amount for as long as they have those loans to pay off.
That means that the smaller airlines that can't aford the new jets will continue to be feasible for awhile, until five or ten years later when the big airlines finish paying off the loans, and at _that_ point we may see some big price drops. Of course by that point it may be too late for the smaller companies to switch over, and i'm not sure what they'll have to do to stay competitive.
This isn't to say that the idea isn't really cool and would make good economic sense for the long term, but the idea that a medium increase in efficiency will "slash the cost of air transport" all by itself is a naive view of economics. (I won't pretend my view is perfect, but i'm trying to be a _little_ more realistic)
As for the windows issue, it would be cool if they could replace the walls and ceiling with polarizeable high impact plastic of some kind. Make the entire thing into a skylight! It wouldn't give you much view of the ground unless you were near one of the edges, but it would still help everyone feel less cramped i think.
This Space Intentionally Left Blank
Wonder why they picked NorthWest's colors for their graphic?
EnkiduEOT
There is no trap so deadly as the trap you set for yourself
-Raymond Chandler, The Long Goodbye
There's an international standard that all commercial aircraft have to fit into a 262ft (80m) square footprint, which drives design issues like how far apart the gates have to be at airports.
This thing has a projected wingspan of 289ft (88.1m), which means that at airports where it can't "accidentally" fit, special gates will have to be built for it. (Then again, it'll probably have such a weird arrangement of doors, that you'll need multiple oddly-arranged jetways anyway.)
And -- would the average person fly in a radically new, untested airframe?
Boeing has a solid method of both ensuring an plane's good design and ensuring the public that their plane is airworthy.
The send the design engineers out with pretty much all the first flights. As a budding mechanical engineer, that's damn good motivation for me to make sure my plane is designed well.
Alcohol, Tobacco and Firearms should be the name of a store, not a government agency.
This must have been said by people watching Orville and Wilbur.
If you don't want to repeat the past, stop living in it.
Performance pretty much sucked, so they switched the powerplants to eight turbojets (this was the YB-49) which solved the performance issues. Around 1949, Northrop started to think about a civil version, supposed to hold 80 passengers, IIRC, with one big window in the front, the flight deck above.
A combination of (some say) conspiracy, political pressures, strategic considerations, and cost killed the program. Much of the research went into the early development of the B-2 (also by Northrop, almost 50 years later).
At any rate, none of these machines were computer controlled. Not saying that's how it will be on Boeing's machine (probably will be--the 777 is fly-by-wire, as are all the Airbuses), but it's not strictly required for a flying wing.
--Ribald
This is for trans-oceanic, not regional travel. It's efficiency will give it a monster range, so you can go LA-> Singapore in one shot, I think. For the distances that trains are practical, airlines tend to prefer smaller planes (eg 737s) and more numerous departure times.
It's not an SUV, it's a freighter for the skys.
"one treats others with courtesy not because they are gentlemen or gentlewomen, but because you are" --G. Henrichs
Sorry to be lame and reply to myself -- but i think it's better than being lame and keep a bunch of ideas mis-communicated.
1) Airbus 380 has wingspan of 79.8m -- and many airports (the stat was ~20% last i heard) cannot accomodate its size. by comparison, Boeing 747 has a wingspan of 64.4m
2) This proposed design has wingspan of over 88 (88.1?) meters. so if airbus 380 does not fit into some of today's airports, this will be having lots of troubles
3) the rate of new airports being built in the US is diminishing to a handful per year. Most metropolitan areas are surrounded by suburbs and new airports to accomodate new (bigger) planes is out of the question. this leaves us with a serious dilemma: our current airports do not fit these things, and there arn't any new airports here to take their place.
4) before anybody asks -- yes airports can be re-fitted. Chicago-midway, for example, is currently undergoing something like that. but even AFTER refitting, A380 will *still* not fit in ~5% of the airports. (something to do with runway length, gate width, etc etc that makes it economically or logistically impractical to refit) so i do not expect refit to be all that powerful a solution to our new one-wing design.
so... like the concord -- this might come off to be one of the vanity flights offered at only a few airports (for a different reason, of course) -- but it *would* make an excellent alternative if it could land on, say, water. so instead of cruise ships, we can ride THESE all day -- and maybe the top observation deck can be made with a glass ceiling dining room, etc etc. the possibilities are great for these planes -- but i just don't see it in people-carrying NY-Tokyo flights.
My life in the land of the rising sun.
These days many airlines are having trouble filling their 400 or 200-passenger jets. If they're only able to book a maximum of 200-400 passengers on these planes, the airlines are going to end up paying even more for fuel per passenger than they are now.
There went that idea. Next?
Yah, but plenty of those planes currently in the air are nearing their end-of-service, so I imagine that as airlines look to replace them, they will look closely at this design that Boeing claims will save them tons of money.
Perl - $Just @when->$you ${thought} s/yn/tax/ &couldn\'t %get $worse;
I notice several posters questioning why, if this thing's so great, we haven't seen it before. While this would seem a rather odd question on a TECHNOLOGY based forum such as Slashdot, I've tried to offer a bit of an explanation.
Prior to now the BWB was not an option for several reasons, perhaps the greatest being the design of a pressure vessel (remember airliners are pressurized). Typical tube and wing style airliners solve the problem of the pressure vessel by taking pressure load in hoop tension. While this is, from a structural perspective, the preferred way to carry the pressure load, it is not feasible to do so in a BWB aircraft, as the vessel is shaped more like a pancake. This brings is to our first point, modern composites permit a pancaked pressure vessel that will tolerate the load at an acceptable weight. The materials available prior to now (aluminum) were simply not workable in the design of such a pressure vessel without an enormous weight cost-thus vitiating the efficiency increase of the design and sending costs prohibitively high.
In addition to the materials issues, another factor that made Blended Wing aircraft heretofore infeasible was the fly-by-wire systems needed to solve the stability issues associated with the design. Although Northrop's early flying wings flew without benefit of computers, they did exhibit some nasty characteristics and were very sensitive to center of gravity changes, issues that aren't acceptable in a commercial airliner.
That said, the fly-by-wire systems of today eliminate the stability issues that plagued early designs. For those of you who believe computer controlled and stabilized aircraft are not feasible for service in commercial applications due to safety considerations, look no further than the Airbus A-320 & A-319. Both of these aircraft use full authority fly-by-wire. All control actuators are electro-hydraulic, when the aircraft is in autopilot, the stick does not move when control inputs are made by the autopilot, and the throttles sit fixed in a "cruise" detent-regardless of actual throttle position as seen from the perspective of the engine's fuel distribution unit. Further, the aircraft has full trim authority, constantly trimming to 0 G, with no provision for pilot override. What all of this adds up to is that there is no physical link between the pilot and the control surfaces of the aircraft. When the pilot makes an input, the computer decides if, and how much, a given surface will deflect. Complex as it sounds, it works, and works well, and given the degree of redundancy required of flight-critical systems (10^-9 I believe) for certification, the likelihood of full failure is less than today's direct-hydraulic systems
With these problems solved, the design makes infinitely more sense than the tube and wing designs of old. It is much more fuel efficient, and given the overwing engine mounting, much quieter, as aircraft with engines slung under the wings reflect noise off the wings and back at the ground, whereas overwing mounted engines reflect the noise up. Overwing mounted engines are also less susceptible to ingesting debris, and bird strike on rotation.
In short, the BWB is a better way to design an airplane, and this note only scratches the surface as to the reasons why. We haven't seen them before because they weren't feasible before, but now that they are, let's hope Boeing pulls up their socks and builds one
That's one of my gripes with modern airliners - they have such teeny, hard-to-see-through windows. My guess is that they make them that small so the airframe can withstand the streeses of pressurization.
The DeHavilland Comet, one of the first jet airliners, was originally built with large square windows. About a year after they went into service, Comets started falling out of the sky because of metal fatigue from pressurization. Since then, airliners have been designed with those tiny round windows we've all come to hate.
It would be really nice if the BWB was built with big panoramic front windows, so anyone could stick their heads into the aisle and get a decent view. But I don't know if they can do that without comprimising the structure.
Meldroc, Waster of Electrons
Although I agree that aerodynamics are prevalent in aeronautics, there's MUCH room for improvements in engines as well. I don't buy the claim of 30+% less energy consumption with only a new design. I bet the engines they intend to use are part of these 30+% as well.
Just look at cars... In less than 5 years, at least in Europe, gas engines have seen their consumption reduced by more than 40% at equivalent power, with close to no progress at all in aerodynamics. Progress has been even more spectacular with fuel engines. Worse, the friction car engines have to face is higher than in the past (higher total weight, larger width of tires, and recently greater height of cars - see the new Honda Civic). Nowadays, all of these improvements are barely applied to aeronautics. They would help at least on non jet thrust powered airplanes, and that means the vast majority of planes out there. But I'm confident that at least part of these improvements (stratified load for example) could be applied to jet-thrust engines as well.
As a side note, sound is energy as well... The noise generated by aircraft engines is awfully high, especially with jet thrust engines, but the vast majority of this noise is due to frictions in the engine itself... Instead of adding isolating material into the plane (which brings in more weight, hence more energy to move that weight), a better way to solve the problem is just to reduce the friction into the engine itself...
It looks like the BatJet Tonight on our featured flights, we have Batman, and Batman returns at the choosing of Michael Keaton, our honorary resident pilot.
/^[A-Z0-9._%+-]+@[A-Z0-9.-]+\.[A-Z]{2,4}$/i
The obvious answer is to fit big television screens showing what is going on outside, making every seat a window seat.
Yeah. Real obvious. except that it would be DUMB. That'll tack on quite a few dollars to your ticket, as well as take up too much room.
What they really need to do is give the whole plane a glass bottom. Then every seat is a window seat...when you look down.
Your
I want the optional map overlay so I can see where the heck I am.
The living have better things to do than to continue hating the dead.
But "Funny" is just plain cruel!!!!!!
Boeing, fielding a flying-wing-type design?? Sheesh... Boeing is the reason these sorts of planes weren't commonplace 50 years ago!!
Listen, children, to today's aerospace history lesson....
Waaaay back in the late 1940's, Boeing was the darling of the newly formed US Air Force, on the strength of their sturdy, functional WWII bomber designs (B-17, B-29).
However, they were not the only manufacturer capable of designing high-capacity long-distance aircraft.
One of the sucesses of the WWI aircraft industry was a startup called Northrop Aircraft. Led by the brilliant and iconoclastic designer John Northrop, they had started with nothing but ideas, but by the end of the war had already provided one remarkable aircraft to the war effort, the US' first dedicated radar-equipped night fighter, the P61 Black Widow, which decimated Japanese airpower in the latter stages of the war.
John Northrop was well versed in our enemies' aircraft design efforts. He was particularlry intrigued by the work of Germany's Horten brothers, who did pioneering work on "flying wing" aircraft. Much like Boeing's "blended body/wing" designs, there was no separate fuselage; the entire aircraft contributed to lift, and hence were astonistingly efficient.
(Aside: the Hortens also experimented with the use of evading technologies. Their early wings were built of plywood, but their shape, with no corners, no edges, no right-angle "reflector" areas between tail fins or between fuselage and wing, made them unusually hard to detect on the primitive radars of their day. The Hortens added conductive layers of charcoal to the plywood layup, reducing the already low signature dramatically, creating the world's first "stealth" aircraft.)
In 1940, after the defeat at Dunkirk, the US Army Air Corps was convinced that Britain would soon be overrrun by Germany, and realized that it had no way to strike at European targets from North America. They were desperate to develop a bomber that could reach the Germans if England fell. So they put out an open competition for a transcontinental bomber.
Boeing had already designed a pressurized, high-altitude bomber, the B-29, which later in the war would help decimate Japan, both with conventional ordnance as well as the the first atomic bombs. They offered up an improved version of the B-29 to the competition. (yawn)
Another established airframer, Consolidated Vultee Aircraft (later Convair), borrowed heavily from Boeing's B-29, but proposed a much larger, eight(!)-engine monstrosity, the YB-36, IMHO one of the most homely aircraft ever laid out on paper.
Northrop, on the other hand, shot for the moon. They proposed a radical flying wing design, far larger and more sophisticated than the Horten designs. For the sort of long ranges missions the USAAC was proposing, the efficiency of the flying wing gave it a distinct edge. With a weight similar to the B-29, it had the range of the far larger Convair design, with the same bomb capacity. Northrop had already built experimental flying wings; they folded their accumulated experiment into an amazing prototype, the four-engine YB-35.
Suffice it to say, the USAAC wasn't all that open-minded to such a radical design. Boeing's design was a non-starter. Plus, at the time the congressional delegation from California had leadership positions in key appropriations committees... so the huge, ugly, inefficient B-36 got the nod for full production.
But that wasn't the last of Jack Northrop, or his flying wings.
Almost before the ink had dried on Japan's surrender on the deck of the USS Missouri, tensions with the USSR had escalated to the point where the US military had to consider yet another intercontinental war scenario, but this time the ranges were even longer, up over the North Pole. Hence, another design competition.
Convair's B-36 proved to be a disappointment; even retrofitted with newer turboprop engines, it didn't have the sort of speed and range the new US Air Force needed.
Boeing went back to the well yet again, with a technologically modest design; huge, conventional winged airframe, with four pairs of new turbojet engines to get it off the ground.
Northrop went back to their YB-35, refined the design with the results of the extensive testing they'd done on flying wings since the YB-35, scaled it up for enough volume to carry the bombload and fuel required (and then some!), and replaced the prop engines with turbojets, to create the YB-49.
By all accounts, technologically the YB-49 cleaned up. Northrop was so enthused by their success, they set about designing commercial passenger and cargo versions.
But once again, politics won out.
The details are a but hazy, but Boeing lobbied all the right people very heavily, and in a decision that surprised the entire industry, their design was chosen to become the first nuclear-era strategic bomber: the B-52. Northrop was howling mad, and were quite public with their displeasure.
Just to make the whole affiar that much more scandelous, the Department of Defense sued Northrop, claiming that since the YB-49 was designed for them, they owned the design. They won, and the blueprints vanished from history, precluding the commercial version from ever seeing the light of day. The prototypes and test aircraft were ordered cut up for scrap, to prevent Jack Northrop from embarassing the Air Force with a better plane.
Dont' get me wrong, the B-52 has proved to be an amazing aircraft; whiel far from efficient, it's sturdy enough to allow almost endless modifications, and that has allowed it to survive as a front-line weapons platform even today, 50 years after it's first flight.
But stop and think for a moment where we might be today if the better plane had won, validating the general design. If Northrop's commercial models had been allowed to compete with the more conventional early Boeing and Lockheed airliners.
Yeah, the Blended Wing/Body looks radical in the current context. But it shouldn't.
Learn from the mistakes of others. You won't live long enough to make them all yourself.
For more information on flying wing stability, here is a talk by Jack Northrop to the the Royal Aeronautical Society.
Jack provides a very thorough discussion of lateral stability (your "hunting" problem) in the latter parts of his talk, where he describes a simple method to solve this, without computers:
For you non-aeronautical engineers, "deadbeat damping" means "rock-solid stable". The "rudders" he talks about are split flaps at the wing-tips, same as those used on the B-2.
The real problem with a BWB as I see it is the wingspan and the position of the passenger doors -- how the heck is that thing going to fit into most terminals? The link shows a planform comparison of the BWB with a 747-400; the 747-400 wingspan is much smaller, 212 feet compared to the BWB at 289 feet. Regular 747 wingspan is 195 feet.
This is a fundemental problem -- if an airline can't fit the thing into its hub-airport terminals, they're just not going to buy it, no matter what its other benefits.
I think if passengers and cargo operators are willing to give the blended-wing body airplane a chance to succeed, the plane will definitely have some major advantages.
First, the plane uses substantially less fuel on a seat-mile basis than even the Airbus A380. This means the BWB could carry 200-250 more passengers per plane for the same range as the A380-800 (8,000 nautical miles). If Boeing is willing to keep the passenger capacity at around 550 passengers the plane could achieve perhaps the last major goal of commercial aviation, the ability to fly between London, England and Sydney, Australia non-stop in both directions year around (the distance is about 9,000 nautical miles on a Great Circle route).
Second, because the engines are located on the back of the plane, this could mean lower noise levels, meeting the upcoming ICAO Stage IV noise standard easily.
Third, since the entire plane's shape becomes a lifting surface, that could mean the BWB will probably need less runway lengths than the A380-800. Also, the BWB's landing gear placement will also mean compatibility with today's airport taxiways.
Fourth, because the BWB's length from front to back is about the same as a 767-300, a simple incorporation of folding wingtips could mean the BWB can easily fit into airport parking gates now used by the 747--no need to build parking gates that comform to the 80 x 80 meter standard that the A380 will require (an very expensive proposition for many airports).
Finally, because of the unique interior volume area of the BWB, Boeing could easily design much more efficient seating areas and airlines could put in large lounge areas or for the first time turn First Class seating into roomettes like you see on railroad sleeping cars.
Let's face it folks. Air travel is going to continue to increase in popularity, and given the space restrictions and noise abatement rules at today's airports the BWB could become the new queen of the skies by 2015.