Where is "Animal"? Clean engines, wings that fold: Boeing dreams of futuristic jets By Dominic Gates Seattle Times aerospace reporter PREV 1 of 4 NEXT=20 =20 =20 =20 =20 =20 =20 =20 =20 Related Less maintenance means more revenue for new jet's buyers=20 When Boeing names an airplane design after a Muppet, it must be pretty diff= erent. Two small teams at the company are re-imagining the airplane in futuristic = configurations that sprout wings, tails and engines in unexpected shapes an= d places. The research, illustrated in internal documents obtained by The Seattle Tim= es, aims in two directions: low-cost airplanes, and environmental-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 airplan= e with main wings radically swept forward rather than back, and miniature w= ings on the front. Then there's the "Fozzie." It has a "Pi-tail" =E2=80=94 two vertical tails = joined by a piece across the top, and sips fuel because it flies slower usi= ng open-rotor jet engines that resemble old-style propellers. The concepts are "intended to help us focus technology on a future out beyo= nd the horizon," said Dan Mooney, Boeing vice president of product developm= ent, who directs both research teams. The documents show Boeing has looked at other concepts as well: a supersoni= c business jet; a megasize freighter; airplanes that use biofuels or hydrog= en; and even a "reduced crew" airliner =E2=80=94 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" an= d the "green" planes for further research this year. Both teams have begun = work with engine companies on the various propulsion alternatives. Mooney gave a glimpse of some of these designs late last month at an Americ= an Institute of Aeronautics and Astronautics conference in Washington, D.C.= But attendees didn't get copies, and these images have not been published = before. The Boeing documents include assessments of very similar research projects = that its rival Airbus has sketchily mentioned at scientific conferences. =20 In an interview, Mooney declined to discuss proprietary details of the desi= gns but offered insight into what his research teams are up to. He said the latest airplanes being sold today, such as the 787, are designe= d 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 c= osts, noise or other factors may become more important and reshape what air= lines want. "We need to be developing technology today to allow us to be ready for thos= e uncertainties in the future." The Muppets 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 ai= rplane structures =E2=80=94 each with its own whimsical code name. (The Mup= pet theme may be a reference to the song Kermit sang on "Sesame Street": "I= t's not easy bein' green.") =E2=80=A2 "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 t= hey join the fuselage right at the horizontal stabilizer. And most radicall= y, the wings sweep forward, not back, lowering aerodynamic drag and increas= ing maneuverability at the price of some stability. Keeping this tail-heavy= aircraft stable in flight requires a canard =E2=80=94 those mini-wings up = front. The plane would be a wide-body seating nine abreast. =E2=80=A2 "Fozzie": Ultra-low fuel burn. The airplane is designed to cruise= at a much reduced speed =E2=80=94 500 mph rather than the typical 600-plus= mph of current jets. That would add an hour to the typical transcontinenta= l 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 tod= ay, but without the usual duct encasing the fan, Mooney confirmed. At slowe= r speeds, this offers great fuel efficiency. One internal drawing shows the rotors on the back of the engine, as depicte= d in The Seattle Times illustration; another shows them on the front, the m= ore usual position. "That speed is not acceptable in the current marketplace," Mooney said. "Bu= t in the future, if fuel burn becomes an even bigger driver, airlines and p= assengers may be willing to trade speed for lower fuel costs." Back in the 1980s, Boeing flew an experimental prop-fan engine on a 727. Th= at research ended after oil prices fell and removed the incentive to save f= uel. =E2=80=A2 "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. =E2=80=A2 "Honeydew": Low fuel burn. Another wide-body, this aircraft seems= to be a meld of the traditional "tube-and-wing" shaped airliner and the of= ten-touted "Flying Wing" design that produced the B-2 bomber. The resulting delta-shaped wing blends in a graceful curve into the fuselag= e. 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 in= triguing compromise. Since April, Boeing's Phantom Works research unit, in collaboration with NA= SA and the U.S. Air Force, has been doing wind-tunnel tests on a small-scal= e, 21-foot-wingspan prototype of a Flying Wing or Blended Wing Body aircraf= t 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. Time for a change 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 presi= dent at Boeing's Phantom Works who worked on prototypes. Like the Detroit carmakers who wheel out fanciful concept cars that never r= each the showroom, Boeing may never build an airplane that looks like any o= f these images. Still, Mooney said, "Most likely there'll be parts of the technology or par= ts of the configuration that will find their way onto products of the futur= e." This fall, the internal documents indicate, the advanced-concepts teams wil= l recommend features from their designs that might be used on the replaceme= nt for the 737 single-aisle jet, which is expected to enter service as soon= as 2012. "Our concept-airplane folks stay closely in touch with those working on nea= r-term programs," Mooney said. Hans Weber, a San Diego-based engineer and aviation consultant, said he's n= ot surprised at most of the Green Team designs =E2=80=94 shown to him by Th= e Seattle Times =E2=80=94 because many of the elements, from unducted fan e= ngines to the use of canards, have been studied for a long time. Only the Honeydew model struck him as odd, because he wonders why Boeing wo= uldn't go for a full Flying Wing design rather than a half-measure. But he warned that it would take a great deal of work to get such concepts = as the Kermit forward-swept wing certified as airworthy by the Federal Avia= tion Administration. For Mooney, it's far too early to worry about certifying any specific desig= n. He's directing money into these projects only to find out which of the p= otential technologies may make sense. "There's always business pressure on us to invest in the short term, where = we know we are going to get a benefit," he said. "But we think it's importa= nt to have an ongoing investment in the longer term." The idea, Mooney said, is that Boeing "be ready =E2=80=94 depending on wher= e the future goes." Dominic Gates: 206-464-2963 or dgates@xxxxxxxxxxxxxxxx =20 Roger & Amanda La France