cz 10 OD V .0 0 M z 0 All LUXURY CARS FOR LESS: Premier and Dynasty vs. Clera and Sable pproved For 9 07 H '9V 6 0 Approved For,Release 2000/0.8/08: CIA-RDP96-00789ROO03.0081000I.-9 What's News lar P STceun' ce Finally: Stealth! So we're finally going to get a look at a real Stealth airplane. We're pleased that it will look pretty much the way we showed it on our September 1986 cover. We've dug up a good many new details on the B-2, as you will find in the piece starting on the next page. Video ball and chain climbed into the pilot's seat. A few minutes later the 140-foot rotor blade lay on the floor, smashed beyond repair. Scott Larwood, student director of the project, says the problem was that Ito weighs 15 pounds less than Eulate.: That apparently changed the helicop- ter's balance, so. it pitched forward when ground-crew members let go. Now the team is evaluating whether to rebuild the single wing or change the design to a three-bladed rotor. improve performance and durability of car engines, the SAE says. They will soon be available, and you can tell when you're buying the new lubricant by checking the doughnut-shaped symbol on the can. What's different about SG oils? Tom McDonnell, chairman of the SAE fuels and lubricants division, says SG oils have significantly more disper- sants, detergents, oxidation inhibitors, and anti-wear agents. In March POPULAR SCIENCF'S cover showed the Mitsubishi VisiTel-a new low-cost videophone that transmits pictures on ordinary phone lines. So 1 was fascinated recently to spot the same piece of equipment in a photo- graph in The New York Times, espe- cially because the accompanying piece was about keeping jail crowding down in Anne Arundel County, Md. It told of a man who had been convicted of drunk driving for a third time. He was sentenced to two months of night- time house Arrest and was also told not to drink. How do authorities make sure he is at home-and sober? Twice nightly, at random times, they call him on the videophone. He answers with his VisiTel. Not only can authorities see thaIt hes home, they can also watch as he uses a hand-held breath anh- lyzer, which displays blood-alcohol levels in bright red numerals that can be read over the VisiTel. So far seven people.under house arrest in the county have been issued the units. For the county it's cheaper than keeping some- one in jail. And the customers are rea- sonably happy. One unidentified user complained that he was sometimes awakened at night by the call from the county. .' "I'm not happy about it," he said, "but., it~ surebeats going to jail," Pedal-p9wered plunge . ; I '.. I , The Da Vinci, II finally got off the ground-maybe. The pedal-powered helicopter built by students at Califor. nia Polytechnic State University [May] quivered briefly as pilot Andres Eulate' pedaled furiously and may-just may -have lost contact with Earth briefly, Nobody is sure. Then bicycle racer Ted Ito, fresh and burning to make history, Energy roundup 0 More news on the coal front: A decade ago, a way of burning coal called fluidized-bed combustion received con- siderable attention, most recently in this magazine in December 1981 ["Multi-fuel Combustor"]. In such a system coal and crushed limestone are mixed, then fed to a furnace in which they burn while suspended ina churn- ing mass on a column of air. As the coal burns, the limestone absorbs the sulfur dioxide it produces, ending or reducing the need for costly wet scrub- bers. Now two major fluidized-bed plants have come on line-a I 10-mega- watt plant at Colorado Ute Electric Associations Nucla station and a 130-megawatt installation at Northern State Power's Black Dog plant. The technology could later be useful in reducing'acid rain and other air pollution, The British. have put another $15 million into a long-range project to develop dry-hot-rock geothermal power. Engineers are investigating a site in*" Cornwall and hope to start building a plant in 1991 when preliminary en- gineering work has been completed. They calculate that the site contains enough heat 6 generate between 750 and 3,000 terawatt-hours, of energy, enough to supply power to Bouthwesi England for the foreseeable future. Befter oil The Society of Automotive Engineers has recommended that car owners start using a new type of engine oils, labeled SG, The new oils have been compounded to reduce engine wear, SG oils should An Audi 12-banger?. BMW has.one [Feb.]; Daimler-Benz is developing one, as is Cadillac. Now the (unofficial) word is that Audi will have a 5.3-liter V12, or maybe a V10, in a limited edition, four-wheel-drive, active-suspension, .high-priced super coupe. Audi worft confirm the rumor. Metric again? The count is down. Now only Burma and the United States still use English measure. Even England has scrapped this system. You may remember that the Metric Conversion Act of 1975 set up the goal of slow conversion in the United States, and envisioned a slow fading away of feet, pounds, and quarts. What faded- instead was the act. Now the Defense Department is go- ing to give metric another nudge. Any- one bidding on a defense contract must now use metric specifications. The reason: simple economics, says the Department. The move will en& NATO's expensive dual inventory Sys- tem and make it easier for foreign companies to get involved in joint development programs. One Pentagon official recalling the distinct lack of enthusiasm with which the country, received the general metrification attempt in the mid-70s quipped, "We're not trying to change the way people live-just the way they fight." 0111~ EdHor-In-Chlef JULY 1988 145 Approved For Release 2000/08/08 : CIA-RDP96-00789ROO0300810001.9 Approved For Release 2000/08/08 CIA-RDP96-00789ROO0300810001-9 What the Air Force isn?t saying-critical.elements not shown CONDUCTIVE INkER WING STRUCTURE MULTI-LAYER ABSOF(SENT COVERING g (C) are ITX~ constructed to minimize radar Ing edges of the wyin refl.-ction. First, they are covwi, , h . I A Second,V ra_,M,iiiI gna s. r ` - - gd o m s6r1 f th f A- , NCOMING en SIGNAL' VQ in 4 0 o , u I n gungyg -With f dq-R~AL-gv_ tjjbej~1Ejjch hexagon is,filled W rial, ORBENT MATERIAL Increasing C RADAR ABSORMON in A density from the outermost edge to the in R-ABS nermost. RAO An incoming radar signal first strikes and is partly ROCKWELL INTERNATIONAL SCIENCE CENTERabsorbed by the multilayered covering. The rest goes into a " hexagonal ` cell. As it penetrates, it continues to be Pro" ~ The I Ing of the B;2 released by the remaining Air Forcei signal of&lal that e 6 Pa ntm strikes the gressively absorbed. - -- ---angled surface at 6d, the (above) shows4Q-9 4a hig- rear , Vg4 is ' reflected 9' in 1 a ! zigzag pattern ,XE --"4 pods. on the wing' Two dT sorbed toQjh_ trailing edge a alongtbis _at back 0 through * the q cell, continuing to be ab : are obvionslylor engines, the third. is and proba- even Iqnger Oath. Suth'o,techniquV1%WV1iep unate- ITly elip ~' i A- bly weapons. W #Ofa-~6's _iO shown tio`n-. - Experts guess from the wing edges. "It's a Roach Motel rjidar reflec that in the absence of any vertical-for stabilizer, directional radar waves," said one observer. "They Icheck in, but control (A) might be achieved *Ith'7they 40S0~iJ'vWjAp6-.,_ don't - check out." Although it is not sho" in the official SpbIlerkrAised on WhVVU4 and not Air the other might intr6- Force V- vers* t ome Fl experts i t,b1nkAh66AnQ- ht p:~Pods_.~ l w i 'othl' h ' i W6u i - a~ fhkf7iii ~W Wh ;; d (D) bra . n re t en urn. o us ra at r aps m l on - 9i y ng a duce draj , t g be mounted in the most forward partsa of the serrated trail- radar signal strikes a normal contoured surface of-the, ing-46dje; because that would put kind'found them closest to the center on most aircraft, a glint is transmitted back in of gri'avity, wh6re they would havealmost minimum effect on pitch. any direction, making the target easy to see on radar. critidal (B). Air probably flows A through faceted surfice, on the other hand, tends to reflect sig- the Intakes, on 'App ~ 'of the wingnals through an S-duct to the in ' directions slightly different from the direction from t e cii i ngme compressor-a strong potential which .efigines. Thus h they came, so they do not return to the originating source of radar echoes-is hidden radar.ko-surface, of course, would frominegming radar sig., Z also be coated with ; _ I di d fl ti Aid 16 UAV nals. A._yA diffuser -r%dar- P_ & uce re n ec ons bs0r re n any ate * g-"-iirder to spot by satellite-bornerection. heat One Un possible wide pl rna countermeasure that might be applied sensors. A thin additional Inlet against called a boundary-layer gut- a stealth aircraft3A bistatle i;vidar, in which the trans. ter can be seen below each main mitter Wet. These probably- servo is ' at f the to one Fi location t "n t the receiver at another (E). The round or satellite transmitter either l nal transmitted b wo purposes. s rs y , a kWer o g p g surface- of Aef, wing can o off1hroughcan this Inlet, ricochet off the target and be received by a separate smoothing the flow into the engine.ground Second,-4.09 additional receiver. Another advantage of this arrangement-, to *W6d- withthe jet to co&_H~AirthorThe listening ground station is Passive; because it is radar-si- Apft%tewhan ng and trail- lento Its location cannot be determined by the attacking plane. g&dgeteqjVb3he gled Fur1k 10 CIA-RD P96-00789ROO0300810001-9 48 1 POPULAR SCIENCE MAGNETIC AND ENERGY DISSIPATING RESISTIVE CARD tOATING ["Advanced-Design to carry two radar transponders. That's because if a sin- gle transponder failed, the plane was nearly invisible to radar. Some versions of such materials reportedly have been considered for the B-2, including a.carboy5laft&-fiberglass composite developed for the Hound Dog missile and a black fiber-reinforced graphite skin. Lockheed's stealth fighter is reported to be made of f4baloy~glass-fibers embedded in ,plastic made by Dow Chemical. '-Special coatings also help suppress radar reflections. The *831-71,- for example, is said to bA painted with 4Lx#dw1. ,jAtive paint,This does not absorb radiation, but rather al~ conducts it over the surface of the structure, cooling off hot spots that may develop at edges, corners, and other such places. The substance used on the SR-71 is called "iron-ball" paint, apparently because it contains micro- Approved ForRelease 2000/08/08 -RDP96-00789ROO030081 0001 J CIA 9 Irec frog the next generation of manned bombers di tly into the world of stealth. The Reagan administration later re- instated a revised B-1 program, now the B-113- The B-IB, now going into operation, is scheduled to serve as a bridge to the time when the B-2 will be brought into operation- the 1990s. Engineerin g secrets of the plane raAar can't see daunting task-building an airliner-size flying struc ture that even super-sensitive, military radars caidt find. Firstjob: reduce what engineers call the RC&--radar cross section. The smaller the RCS, the smaller the echo re turned from a radar signal of a given signal strength, A clue as to how this might be done appeared shortly after World War 11, when radar had changed the rules of the military game. Engineers noticed that some planes returned far larger radar images than others of essen tially the same size. "The problem is that an aircraft, or parts of it, can act like an antenna, reradiating radar sig nals that strike it," said M. William Frasca, an expert in radar-absorbent materials. Some planes were better natural reradiators than oth- ers. In particular, experts pointed to the Russian TU-95 Bear and the British Vulcan bomber. The TU-95, with huge eight-bladed propellers, a tall vertical stabilizer, and many sharp angles, returned a massive radar echo. The Vulcan, by contrast, was a wedge-shape flying wing with the engines buried inside and small vertical fins. At some angles it virtually disappeared from radar, And at no angle did it return an intense echo. Over the years engineers have come,,.~ip with an ever clearer idea of why the Bear and Vulcar(looked so differ- ent to radar-and how they could design a stealth air- craft to take advantage of there principles. For example, the spinning compressor blades of a turbo jet inlet send back radar echoes like a beacon. Sharp edges and abrupt angles tend to act like antennas. So do tall vertical sta- bilizers. "The more you make something into a smooth blob, the better off you are from a radar point of view," says R. John Hansman, an aeronautical engineer from the Massachusetts Institute of Technology. But designers of all-out stealth aircraft are concerned with more than just the shape, The materials used in the structure are also selected to help with the job.-Carbon.- fibermaterhilgZ1or example, are made by embedding thin filaments of carbon in an epoxy resin. The resultant-ma- terial is as strong as steel but does not reflect most radar waves well. Its carbon-based molecules tend to absorb mi- crowave energy, as food does in a microwave oven. One plane built largely of carbon fiber was'the Lear Fan Lear Fan 2100," June '811 which had paints to make airplanes invisible to radar in World War IL At the same time, German submarines had their snorkles painted with a similar substance to keep British radar from detecting them when they poked above the surface. Absorbent coverings first came to public notice in Janu- ary 1982, when the U.S. Embassy in Tokyo called the TDK company, a well-known manufacturer of electronic equip- ment, with a strange request. The Embassy wanted to buy one gallon of paint. So strange were the events sur- rounding the request that it took until August for Japarfs Ministry of Trade and Industry to give an OK. t turned out, had been developed to, Tha~pai"" -stop' lea4 Kr~ m -ovens.- It. contained. ferriQ~iron- containing compou-'AlUt4and- wa's a~~~of interest to U.S. researchers who were trying to design radar-absorptive coatings for planes. Because Japan bans the export of defense-related technology, and the ferrite paint Wkp~,V-, parently wanted for the stealth project, the Ministry took the matter under advisement. It turned out that another Japanese company-Nippon Electric Co. (NEC) had also developed a similar paint that had been used to coat towers and buildings in sensitive locations to eliminate TV ghosts and scattering of u.4- Wanted radio waves. NEC had worked -out a technique using two layers of the ferrite material separated by a dielectric-an insulator. Such an electronic sandwich, researchers found, could absorb much of the microwave energy striking it over a frequency range of 3.5 to 20 giga- hertz. And, most significantly, most military and commer- cial radars operate in the 10- to 30-gigahertz range. That didet mean the ferrite coating was right for stealtl~ aircraft, however. For one thing, it was too thick and heavy to work properly on aircraft. So work continued. About a year ago a researcher named Robert R. Birge of Syracuse University in New York announced the dis scopic iron rt* I to increase conductivity. covery of a new class of radar-absorbing materials callt _pa ic es ApproAwdaFsG*R~**A* *,40qlf iltAr's retinyl Schiff base salts. The salts were black, resembl! t 4 - Jdrci 1~tn~,opvg A 80 efit of' Luftwaffe experime cesslIft Dpa" , O~ p Approved For Release 2000/08/08 CIA-RDP96-00789ROO0300810001-9 in ,--is.-Tight., That first became reliable news in 1985 when The concept of undetectable planes goes back to 1912, Sen. Barry Goldwater, then chairman of the Senate when the U.S. Army built a heavily muffiered plane with Armed Services Committee, who had seen A ffill-scale a carefully camouflaged paint job. The magazine Aerial mock-up of the plane, confirmed that it was a flying wing. Age noted that the new development "opened up a won- The picture shows that the wings.are, swept -back_about, derful field in aviation, making it possible for a biplane 30,,,dWees, which, as one expert points out, puts the or monoplane to sail over cities unheralded and unseea,~, wingtips far enough behind the center of gravity so that Stealth became compelling for military-plaunm in, 1973. you could put effective control surfaces there-surfaces The Arab-Israeli war broke out, and 40 US.-built plan 'es that would operate with moment arms similar to those were shot down by Soviet-built SA-6 radar-guided mis- you get by having a tail at the end of a boom. The pointy siles, despite advanced electronic-warfare equipment that nose suggests that them,~J§h-ghttpe radarantepij4, was supposed to protect them. Sweetman guesses that by If the B-2 has a large radar antenna, it more likeily-16 a 1975 the Air Force had asked Lockheed's famous "skunk,_ phase&array, radaXin which the antenna is made up not works" run by the legendary Kelly Johnson to produce a of a single dish, butxumeroms -small We-mm stealth aircraft, and that several flying versions-including ~,,distributed along t6'Ving-; the apparently now-operational, but not yet public, F-19- There is precedence as well. When the original-B-1 was have since been flown. modified to its present version-the B-113-its dish-shape A short time later-probably in 1981-Northrop was antenna was replaced with a phased array, a modified ver- tapped to develop what was called the ATB-for advanced sion of the APG-66 radar developed, for the F-16 and used technology bomber-which has since come to be called in that fighter for terrain following and general naviga- the stealth bomber and lately the B-2. Almost immedi tion. A yet more advancedversion probably appears in the ately a battle broke out in Congress over whether the B-2. country could afford to develop the ATB and also keep The, w9jo,gurprising, omission. drawbij wEi--no, developing the B-1-then already underway. sho, ""'i7th "' ' re' With budget pressures building, the Carter administra- coiat,rol surfaces at all. Some experts guess 'at- there a movable wing surfaces, probably placed as shown in the tion canceled the B- I program, apparently hoping to leap- drawings that accompany this article. Some also specu- Continued juLY1988 149 late that a technique called thrus h -vectorir offici t v-selectively l release _ - . increasing and e decreasing thrust a t~va riou s engines-could help in steering the plane. Or it could use reaction'control -squirting jets of high-pressure air through nozzles to change the plane's attitude-a technique used in space- craft. It might even have wings with inner mechanisms that could actually change shape, with trailing edges bend- D mcus RADAR EC ing subtly up A or down, This C would avoid the ~ radar reflec- tions that can be generated by gaps formed by regular hinged control AL surfaces. INCGMING SIGNAL One expert speculated I that the strange ~ sawtooth trail- ing edge could accomplish two purposes. First, if flaps were mounted in the notches, those flaps would be quite far FACETE6x forward and near CONTOU the plane's center "U of gravity. Thus E they RED would not greatly RE affect attitude l 7 or pitch. Second, SURFACE SURFACE straight 'ACE lines tend to reflect radar signaN. By breaking the trail- ing edge up into many lines-no two of them parallel -radar reflections would be minimized. And finally, all agree that the plane undoubtedly uses fly-by-wire tech- niques. Like the famous wrong-way-wing X-29 [April '801 the flying wing is a fundamentally unstable design. There- fore a computer constantly monitors its actions, rapidly SATELLITE and continuously TRANSMITTER applying small corrections to keep -it E in-srAnc RADAR flying straight and level. "I would bet a nice cold beer that it has four engines," said an engineer at a competing aircraft company. The shape of the inlets supports this: The double-scoop design indicates that GROUND ~PASSIVE two pairs of side-by-side engines lurk in- TRANSMITTER RECEIVER side the wing. The drawing is vague about size. Some experts say the cockpit may be deliberately too large to disguise the true size of the plane. Reasons Bill Sweetman: He has heard that the plane has fQur GE '1 F 10 n,4mgin -the ~ picture was generally right, a same power plants-lBboml defense-industry aircraft use jin t e ber. Each gener- re designer told the paper that "Many ates 17,000 pounds times when we 'put of thrust, a total of 68,000 pounds. artist renderings together, we Assuming a standard take a great deal of liberty 0.25 to 0.28 thrust-to-weight ratio 4jigefiffigtlii ngs w9JLe_j are impdr t4ntt- - or a large four-engine pIggically. plane, the weight ,ck would fall into ~ i ' _ i i ~ ~ i i- the 240,000- to here." A Los A 275,000-pound n category with e a wingspan n s jele a A:TiiA_th4fa*4AhftY, havelo " ~' i 'l craft executive- poffit of 130 to 140 ed feet. Others du have predicted t that it would that important features such be as control surfaces had been left bigger and heavier. out, adding, "I wouldift Various reports have guessed that speed bet my grandmother's diamond ring on the accuracy of it "O.$-~~about the nps an airlin- " would be k9mLX 'h ' M that picture. s. er s, and range without refueling some 000 m But informed guesses as to the An old idea actual plane's details can be made. Everyone agrees that the Jlyipg!~ g _z~l ~ 'Win shape__ Approved For Release 2000/08/08 : CIA-RDP96-00789ROO0300810001-9 JULY1,988151 Approved For Release 2000/08/08 CIA-RDP96-00789ROO0300810001-9 -71;4 on the bottom of the 1,760 feet down Anchored, ion-leg plat- ulf of mexico, this record-setting tens -will~"tap oil from beneath the sea floor- Unlike form ~entionAl platforms that sit atop underwater Iix neering marvel is t engi yscrapers, thisnewes airwho:e6d- by~. ~gigantic steel mooring lines. T~ g~,.NAOMI J~, FREUNDLICH illustrations by Linda Richards rom a distance the 'new platform will look just like the others in a growing city of huge underwater skyscrapers that tap the. oil-rich seabeds of the Gulf of Mexico. Clus tered. on the continental shelf, these platforms tap reserves in of around 1,00 feet- But next year, when tug depths of wat~ir nation b(ots haul!Conow Inc.s platform into the Gulf, its desti I explain its unusual design. The platform, with its four huge hull columns churning the water, will move past the urban ~~,7 sprawl to new frontiers: the Greieii Canyon Block 184 oil field, about 170 miles southwest of New Orleans, where water depths h almost 2,100 feet. When the platform is installed in 1,760 reac ept it, will be the world's deepest-ever design. IWGulf of Mexico pioneer is a radically new kind of oil I# production ~platform d signed by Conoco to tap deeper reserves e ~'~'!e ic~nbinically. C6nn'ec'ied to the seabed by 12 tubular steel moor- ing lines, the platform's natural buoyancy creates an upward ''T -under tension and allowing it to stay force, keeping the legs in place in water up to 6,000 feet deep. The tension-leg plat- form (TLP) is stable and cost effective: It requires far less steel h n fixed platforms; and with the help of agile remotely oper- t a ated vehicles (ROVs), it's easy to maintain. But perhaps the most important aspect of the tension-leg design is its portabil ity. Once a TLPs work is done in one oil field, it can be un /08: C :)r Release 200 IA-RDP96-00n" Wftj&andmoved to another site. Achieving PIRsign will require few chs-aes in er ~-or Keiease zumutsims L;1A-KUFVb-UU t D NordicTrack is the Best... Here's the evidence.. A major university performance laboratory con- cluded NordicTrack users burried more calories and.obtained sig- nificantly more cardiovascular exercise than from any other machine teste& More complete workout than an exercise bike The efficient arm exerciser Track pro- on the Nordic vides upper body exercise missing when sitting on a stationary bike, Safer, more thorough exercise than a rowing machine Unlike rowing machines, Bill Koch NordicTrack's arm and leg Olympic resistance can be adjusted silver Medalist independently so you can set the tension ideally for your arms and legs. No lower back pain with NordicTrack. Best way to lose weight il- 11Aerobic exercise is the most effective way to lose weight. 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Other threats Most speculation concerning the B-2 has involved hiding it from enemy radar, because radar is clearly the prime military sensor used today. Yet the plane would be worthless if it could be easily detected and tracked by other methods. For example, sat- ellites with infrared sensors have been highly developed. They're used, among other things, to track-test missile fir- ings by both the United States and the Soviet Union. If stealth put out a hot exhaust trail, it might be tracked by satellite infrared sensors. Three techniques will probably be used by stealth to mask IR. First, the exhaust is apparently below the wing, hidden from direct view by a satellite. Sec- ond, it will probably use a broad diffuser that will change the concen- trated jet exhaust into a wide thin wedge of gases. And third, a small auxiliary inlet beneath the main engine inlet-engineers call it the boundary-layer gutter-may gather air to mix with the exhaust, cooling it and thus reducing the probability of it being seen by an IR sensor. Finally, the B-2 will be equipped with the latest electronic countermea- sures available. Because it will have such a small RCS, it will be possible to use forms of ECM spoofing not gen- erally available. "Radar cross section is only one aspect that's going to make a super penetrator," said one officer who would not speak for attribution. "The other half is the avionics. When you get the radar visibility down very small, you can start manipulating the radar signals so the enemy doesn't see you* 11 Such a combination would be able to confuse the enemy even if he picl~e_(r up a stealth echo. "With a very small target, it's easy to spoof at a low power," says Sweetman. "So you can send back a doctored return. You broadcast something that imitates the return on the first pulse, but then yoV gradually feed in an error that says you're where you're not. The second pulse is a little bit later than the real pulse would be. The third is still a lit- tle more separated, and so on. By this time the radar's logic is locked onto this wrong pulse train, and before you know it, the enemy has got the wrong range." Although there is no evidence to re- veal just where it may stand, there is the possibility of an even more exotic approach. It is a technique called ac- Stea IN [Conti.,ed f,.. page 511 Such figures show why there has been such a drive to produce stealth airplanes for many years. Some, in fact, hypothesize that more has been spent on stealth than on the much more highly publicized Strategic De- fense Initiative, or "Star Wars," proj- ect. But while a stealth bomber would have many important advantages, it would have to give up a lot of desin. able features as well. "The more stealthy you make an air- craft, the less efficient will be its per- formance," says Anibal Tinajero, a defense analyst with the Congres- sional Research Service. The experts agree: Design a plane for maximum stealth, and you give up performance, range, and payload. First, stealthy shapes have rela- tively low inherent stability and con- trollability. Remember Hansman's remarks about the best stealth shape being a blob? Unfortunately, blobs don't have very efficient aerodynamic shapes. For best directional control and stability, for example, control sur- faces are on the tail-well behind the center of gravity. To gain stealth, the B-2 gives up its tail entirely. While the shape of the Lockheed fighter has never been revealed, it is generally agreed that several have crashed during testing, the last of 94 1 POPULARSCIENCE Approved For Release 2000/08/08 : CIA-RDP96-00789ROO0300810001-9