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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.
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.
try clicking the links retard.
BZZT ... the B49 and B2 are full flying wing designs. The Blended Wing is a cross between a traditional swept-wing design and the flying wing concept. Aerodynamically all 3 designs have very different performance characteristics.
... if you hear tell from the old time Boeing employees, Boeing died that day and McDonnell just kept the Boeing name so that people would realize that management was being taken over.
And Boeing merged with McDonnell Douglas, and it was a merger in name only
It is more productive to voice thoughtful opinions (reply) than to judge (moderate) others.
Just how far out to the edge do you think the seats will go? A roller coaster ride? No more than current planes do. The angle of the bank remains the same, only the distance from horizontal increases. I would assume the bwb design absorbs vibration very well. Emergency evacuation is a joke. How many emergencies happened with the plane on the ground and passengers quickly went down the plastic slide? I don't know, but most lethal emergencies involve crashes into land or sea at very high speeds in which nobody survies. If you read some of the other comments, you'd know already this frame is tested and existed for a long time. I'll fly on the plane with the cheap seats and good service, provided there's a good safety record. Maintenance has far more statistical impact than design flaws in crashes.
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"
http://www.boeing.com/phantom/bwb.html
SCO (noun.)- A Slimy Corporate Ogre. Often seeks free money.
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?
Calling this airplane a "delta-wing" is a misnomer. The Saab Gripen fighter and the Concorde are delta-wing aircraft, the BWB is not. The blended wing body is best described as *suprise* a "Blended-Wing Body." It is not just a flying wing, and is not a delta wing.
The "revolution" is in the application of this technology to a practical and profitable passenger aircraft. The idea that blended wing aircraft have not caught on with the airlines or the public is ridiculous. The airlines are in fact eager to purchase airplanes that are more profitable, and the public is eager to save money.
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
The Germans had many revolutionary aircraft, but you have attributed at least three wrongly.
The Me 262 "Schwalbe" was a duel-jet engined fighter-bomber.
The Me 163 "Komet" was a (somewhat) blended-wing rocket interceptor.
The "true" blended-wing aircraft used by the Germans were built by the Horten and Gotha companies. One of which, the Go 229, was actually test flown before surrender to the allies.
A large number of aircraft designs from many German firms in development at the end of the war showed a fascination with the blended-wing design. Even Messerschmitt, who continued building Bf (later Me) 109s right up until the end, was working on aircraft such as the Me 329, a 'zerstoerer' (heavy fighter) of blended-wing-body design.
In fact, we should all be crediting the brothers Reimar and Walter Horten, who began experimenting with flying-wing gliders in 1931. It was their Ho IX which was put into small-scale production as the Go 229.
Q. Who would fly on it?
A1. Anyone looking to pay 25-50% less to fly.
A2. You won't have much choice, the economics will have airlines snapping them up for certain routes.
(At least if the design can achieve the efficiencies and cost reductions they're talking about - plus whatever improvements are made between now and actual construction.)
Of course, for cheap, point-to-point travel, I'm still waiting for my $837,500 Eclipse Jet!
My next sig will be ready soon, but friends can beat the rush!
Bzzztt! Bzzztt! Not entirely right!
7 /
http://www.aerospace-technology.com/projects/74
"The winglets give the 747-400 a fuel mileage improvement of 3% and
their upward angle means that the overall wingspan remains within
the standard airport apron slot."
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
Although the aircraft looks very similar to a flying wing, I think that the revolution has to do with the integration of a flying wing design with what is normally referred to as a 'lifting body'. In a lifting body aircraft, there is no discernible wing, the entire fuselage serves to provide the lift (hence the name). The space program experimented with lifting bodies for a while in an effort to come up with a workable design for a reusable space shuttle. As I recall, one of the biggest drawbacks had to do with control issues. I would suppose that the integration of the two designs has solved those issues.
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.
Fortunately, the issue of engine selection for the BWB is not as serious an issue as you think.
Remember, when the Boeing 777 was being designed Pratt & Whitney, General Electric and Rolls-Royce all designed a new generation of high-bypass jet engines with huge front fans (about the width of a 737 fuselage). The BWB will likely incorporate a variant of these new engines (using three of them), and engine nacelles will use new designs to drastically lower noise levels. In short, the BWB could actually be much quieter than today's widebody jets.
Perhaps its just me but doesn't this plane bear STRIKING resemblance to the B2 Stealth Bomber??
The parent poster was correct, the F-16 was the 1st production fly-by-wire aircraft. The original F-15s (A-D models) aren't fly-by-wire, but the newer F-15E Strike Eagle is.
Yes, most modern fighter aircraft are designed to be inherently unstable, it makes them much more maneuverable.
However, the F-18 is controllable without its flight computer (as is the F-15E). They learned their lesson with the F-16, which was nicknamed the Electric Jet, because of its sophisticated flight control systems. Without electrical power, the F-16 is not capable of human control or even sustained flight: the pilot has about 2 seconds to eject or get the Emergency Power Unit started. Its EPU is actually a hydrazine powered rocket engine in the wing root, very nasty stuff. So the next fly-by-wire aircraft designs factored this into their designs.
Air Canada sometimes do this. When a movie or show isn't playing on the screen they show a live map of where the plane is relative to the ground and your departure/destination. They also throw on info like flight speed, altitude, wind speed, outside temperature etc... It's very useful, especially for those long flights.
If you fly in business/first class it's always available on one of the channels.
Frankly this is much better than having a window since most of the time all you're looking at are white clouds or water.