Posted on 06/06/2006 7:13:58 PM PDT by SandRat
SEATTLE When Boeing names an airplane design after a Muppet, it must be pretty different.
Two small teams at the company are re-imagining the airplane in futuristic configurations that sprout wings, tails and engines in unexpected shapes and places.
The research, illustrated in internal documents, aims in two directions: low-cost airplanes, and environment-friendly planes that will be quieter, use much less fuel and leave fewer pollutants in the upper atmosphere.
In the latter category is the "Kermit Kruiser," a low-noise concept airplane with main wings radically swept forward rather than back, and sporting miniature wings on the front.
Then there's the "Fozzie." It has a "Pi-tail" two vertical tails joined by a piece across the top, and sips fuel because it flies slower using open-rotor jet engines that resemble the old-style propellers.
The concepts are "intended to help us focus technology on a future out beyond the horizon," said Dan Mooney, Boeing vice president of product development, who directs both research teams.
The documents show Boeing has looked at other concepts as well: a supersonic business jet; a megasize freighter; airplanes that use biofuels or hydrogen; and even a "reduced crew" airliner one with no windows in the cockpit, judging by a sketch in the Boeing documents.
But of all the potential concepts, Boeing has prioritized the "low-cost" and the "green" planes for further research this year. Both teams have begun work with engine companies on the various propulsion alternatives.
The Boeing documents include assessments of very similar research projects that its rival Airbus has sketchily mentioned at scientific conferences. In an interview, Mooney declined to discuss proprietary details of the designs but offered insight into what his research teams are up to.
He said the latest airplanes being sold today, such as the 787, are designed to meet airlines' projected requirements for about the next two decades. Designers strike a balance among cost, fuel efficiency, capacity, range and other factors based on those projections.
His concept teams, however, think "out beyond 15 or 20 years," where fuel costs, noise or other factors may become more important and reshape what airlines want. "We need to be developing technology today to allow us to be ready for those uncertainties in the future." The low-cost team, documents show, is studying the benefits of options such as long, thin wings and new engine types. That team has not yet envisioned new structural designs, however.
In contrast, the Green Team, with a broad mandate to address diverse issues of fuel burn, noise and emissions, has considered some widely differing airplane structures each with its own whimsical code name. (The Muppet theme may be a reference to the song Kermit sang on "Sesame Street": "It's not easy bein' green.")
* "Kermit Kruiser": Low noise. The engines sit atop a twin-fin tail, so that the noise is reflected upward. The wings are placed so far back they join the fuselage right at the horizontal stabilizer. And most radically, the wings sweep forward, not back, lowering aerodynamic drag and increasing maneuverability at the price of some stability. Keeping this tail-heavy aircraft stable in flight requires a canard those mini-wings up front. The plane would be a wide-body seating nine abreast.
* "Fozzie": Ultra-low fuel burn. The airplane is designed to cruise at a much reduced speed 500 mph rather than the typical 600-plus mph of current jets. That would add an hour to the typical transcontinental flight.
Attached to a tail with twin vertical fins and a crossbar (called a Pi-tail because it resembles the Greek letter pi) are engines with an "open rotor" or "unducted fan" design.
The plane has a fanjet gas-turbine engine of the sort used on airliners today, but without the usual duct encasing the fan, Mooney confirmed. At slower speeds, this offers great fuel efficiency.
One internal drawing shows the rotors on the back of the engine; another shows them on the front, the more usual position.
* "Beaker": Low emissions. This airplane has the low fuel burn and same low cruise speed of Fozzie. It has low-emission engines and long, very narrow wings perpendicular to the fuselage. The wingspan is such that the wings must fold to fit an airport gate.
* "Honeydew": Low fuel burn. Another wide-body, this aircraft seems to be a meld of the traditional "tube-and-wing"-shaped airliner and the often-touted "Flying Wing" design that produced the B-2 bomber.
The resulting delta-shaped wing blends in a graceful curve into the fuselage. Yet there is still a distinct fuselage at the front.
The Flying Wing design is more aerodynamically efficient. One disadvantage is that most passengers are far from a window. Honeydew appears to be an intriguing compromise.
Since April, Boeing's Phantom Works research unit, in collaboration with NASA and the U.S. Air Force, has been doing wind-tunnel tests on a small-scale, 21-foot-wingspan prototype of a Flying Wing or Blended Wing Body aircraft concept. Flight testing of the prototype is planned for later this year.
The Air Force is interested in the design's potential as a long-range, high-capacity military aircraft. So how realistic are these cool-looking airplanes? "When you look at where energy costs are going in the next decade, it could be time for a change in the rules," said Jerry Ennis, a retired vice president at Boeing's Phantom Works who worked on prototypes.
Like the Detroit carmakers who wheel out fanciful concept cars that never reach the showroom, Boeing may never build an airplane that looks like any of these images.
Still, Mooney said, "Most likely there'll be parts of the technology or parts of the configuration that will find their way onto products of the future."
Suppose its cheaper to buy oil from Muslim countries, but the option is spending a more money on domestic solutions that use less oil, but cost more.
Is there any condition that your "sound economic practice" could support this?
That slower flight time also means that airlines will lose that plane's availability while it's still in the air instead of being turned around for the next flight. Instead of five flights a day the airline may only be able to squeeze in four flights.
When you're paying $100 ~ $150 million for an airliner, you want to make as many flights a day as possible.
"Wel then, we might as well close the patent office because everything that could possibily be invented has already been invented.............. "
As far as what those designs show there isn't anything there that if they were patented the patents would have expired a long time ago.
Boeing finds Dick Rutan?
Most commercial jet engines today are High Bypass variety where 80% or so of the thrust comes from the fan, and not the jet portion of the engine. The UHB was just the next logical progression. Get rid of the fan shroud which is restrictive and is installed only to control noise. But that was the big hang up, however. They are much louder than conventional turbofans, and could not meet the rather strict, in many cases, airport noise ordinances in most communities.
So we continue to pollute more so people who buy houses around airports and still hear the crickets chirp.
Ain't government wonderful?
Yes, UDF (Un-Ducted Fan) was another acronym for them as well.
Actually, they aren't THAT bad.
The EPA says only 2% of the NOx from mobile sources comes from Aircraft engines. Most of the air going through a turbine engine is just air. Only 8% is products of combustion and only .4% is "pollution". Large Turbofans have a compression ratio higher than a Diesel so there isn't much left to come out but soot and the impurities in the fuel/air, which aren't much.
The "typical jetliner" is also 20 years old. Compare a typical Jetliner to 1,000 or even 100, 20 year old cars and the jetliner is cleaner.
If you had said "particulates", you might have a point as most older jets emit tons of these, but they don't really have much to do with smog. Until the EPA cracked down on Diesels in 1997, trucks and trains emitted tons of this stuff, too. These older planes will go the way of the dinosaur over the next 15-20 years and the particulate problem (if there ever really was one) will go away, with them.
As for efficency, the AVERAGE revenue passenger miles for the US airlines is 44 mpg. I would guess LA traffic averages less than 20 revenue passenger mpg.
However, thanks to better gearbox designs since then (which allow the switch to ten-bladed propfans), this will allow for slower fan speeds with far less noise and less danger in case of blade failure. The Fozzie concept could actually work for an airline like Southwest Airlines flying routes under 900 nautical miles in length, where cruise speed performance is less critical. For example, this plane would be perfect for Southwest's intra-California routes and routes between California and Nevada/Arizona; another place such a plane would be useful is intra-Texas routes.
Example: Delta wings SUCK at low speed. Current commercial wing design is a compromise between straight wing (excellent lift, high drag, and poor high speed performance), and a fully swept, or delta wing (low drag, great high speed performance, lousy low speed performance requiring much higher take-off and landing speed)
Now you mixing Turbo-Prop (With gear box), with Turbo-Fan's (No gearbox) The "Open Rotor" UHB, or UDF is a derivative of the Turbo-Fan. No Gearbox involved.
It certainly is an inappropriate name for a "quiet" design.
Soon, we'll be seeing things like composting toilets.
If you spin the prop slower, the plane is going to go slower, which is unacceptable.
As Jesse says, Keep hope alive.
Me, being a realist, know that the UDF is dead. To prove my point, here is the the GE UDF test bed aircraft crashed for a movie prop. No Air and Space Museum for it. After the first flight, everyone pretty much knew it had no future.
I personally think it sounds cool (and if there were only a couple of them, I wouldn't mind), but it aint 1944 anymore.
One of the reasons why the ATR-42/72 turboprop airliners switched from four-blade propeller units to six-blade propeller units was the very fact this allows for slower fan blade speeds for the same thrust output, which 1) reduces noise quite a bit and 2) reduces fuel burn due to slower speed of the engine during flight. Why do you think Lockheed did the same thing with the C-130J, the current model of the famous Hercules cargo transport?
Hence the reason why the switch from eight-blade to ten-blade propfans. With more blades, this allows for slower blade spin speeds with all the benefits I mentioned above.
The Fozzie is a total joke of a design.
Apples and Oranges.
If you put on more blades and spun the prop slower, you may be quieter, but you also aren't going 450 mph anymore.
but where is the Animal design?
ANIMAL!
Nice designs, but I hate the Muppet names.
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