King of Iration Feat. Mr Williamz Fire Blazing Feat. Danman Wondergirl Feat. Tell' dem Feat. Jman Dark Matters Resulting from a long studio work punctuated by concerts on stage or sound system, this album brings together all the influences that have animated for over 11 years the artistic project of the "dubmaker" FELDUB, from Bordeaux, France.
The choice of the artistic collaborations authors, singers, instrumentalists testifies it largely. Infrared wavelengths lie between 0. In discussions on the absorption and emission of infrared radiation, the term black body is used to define an object that will absorb any and all radiation falling upon it, with no reflection. The term emissivity is defined as the ratio of total radiation emitted by an object at a certain temperature to total radiation that would be emitted by a perfect black Infrared radiation body same temperature.
An depends on the amount of most of the energy striking it, engine heat for example, then the surface's emissivity is high, and the surface in this case will get hot and be easily detectable by infrared-guided missiles. If the same surface reflects most or all of the infrared radiation striking it, then the surface will emit small amounts of infrared radiation and will have a low emissivity and a low infrared signature.
A black body at The painted surface of an aircraft at the same temperature will radiate 41 milliwatts per square centimeter. If the aircraft were not painted and had a bare aluminum skin, it would emit less than 4 milliwatts per square centimeter.
Infrared radiation produced by a turbine exhaust or rocket engine exhaust plume, while not as crucial as the infrared signature from hot engine parts, is a factor that must be minimized. This type of infrared radiation is caused by molecular excitation of water vapor and carbon dioxide, both of which are by-products of combustion.
This radiation peaks and at about 2. Surface Table Emissivity of Selected Surfaces. Emissivity Black body 1. It is interesting to note that, although a visually reflective surface not desirable is and radar-signature reduction standpoints, it is desirable for reduced infrared signature reduction.
This is just one of the many compromises stealth designers must deal with in their quest for "invisible" aircraft. Several commercial and military programs have been underway for many years to reduce the noise produced by turbine Noise is engines. Figure shows a conversion developed by Page Avjet Corp.
This engine was used for many early commercial airliners, including Boeing's venerable The conversion, called the Quiet Nacelle Noise Reduction modification, cuts noise emitted by the engine in two ways: by absorbing high-frequency harmonic vibrations produced by the high-speed Florida, for the Pratt airflow exhausted from the primary fan nozzles, and by dampening noise generated by the rotating stages of the engine.
An acoustically treated engine inlet, center body, and bifurcated duct are installed, but no modification to the main engine cowling is required. The air intake cowl is modified with an acoustically treated inner facing, and the body is remanufactured using sound-absorbing materials. Both remain the same size as the orginial.
The original bifurcated duct is modified with a liner consisting center Bifurcated fan air exit duct exhaust treatment in inner and outer walls Fan-exhaust thrust Inlet duct acoustic reverser, stowed treatment Existing aft cowling Center body acoustic treatment Fig. Reducing the aural signature. Fan-exhaust thrust reverser deployed Radio Frequency Emission and Leakage O 27 Nomex honeycomb and preimpregnated graphite fabric. Nomex honeycomb sandwiched between layers of graphite fabric, Fiberglas, and perforated aluminum is used in various places.
The pattern of perforations, hole size, and material-layering sequence vary, depending on the harmonic frequency to be absorbed and the structural requirements of each component. Several new methods have been developed to further reduce the acoustic signatures of military aircraft engines.
They include the use of screech liners in afterburners and sandwich composite skins with pyramidal structures pointing inward to absorb engine noise.
Use of baffles and louvers in areas where airflow is noisy also helps to reduce engine noise. Procedures that reduce acoustic signatures also contribute to rrunimizing infrared Laminated coatings on the exhaust nozzle, and acoustic signatures. Lockheed's YO-3A quiet reconnaissance aircraft used during the Vietnam War had an extremely quiet exhaust system, as well as a slow- turning propeller that emitted very little noise.
Emissions and leakage can be reduced or eliminated by shielding the leaky equipment with RAM placed around avionics bays.
Boron-type composites and ferrite-based coatings Chapter 5 are best for preventing internal radio-frequency leakage and are also used to harden or shield avionics from destructive electromagnetic pulses resulting from er important nuclear explosions. If a stealth aircraft is equipped with radar, the radar should be operated in nonstandard modes so that its emissions won't be detected. One method is to operate the radar with intermediate pulsing, as well as incorporate techniques to eliminate side-lobe leakage and beam scatter.
The radar antenna must be shielded from incoming radar energy, yet also be able to transmit and receive radar energy; this might be difficult and require unorthodox design techniques. The more-pronounced scattered waves, some which bounce back to the radar receiver, are what enable radar to detect the target. The less-pronounced waves are called side lobes and can also sometimes be detected as well.
Stealth technology's main function is to reduce, eliminate, or scatter even further any reflected radar energy so that radar receivers won't be able to detect what of little reflected energy remains. A research team at Sperry Corp. These models featured a variety of aerodynamic configurations and had with triangular- or quadrilateral-shaped wings and reflection cylindrical fuselages stabilizers.
It was found that RAM reduced scatter response reflected energy , but that the amount of reduction depended on the spectrum of radar energy and the model's aspect angle, or the angle at which the radar energy was directed at the model.
The results of the tests showed that RAM reduces RCS by attenuating, or lessening, the magnitude of the target's reflectivity. One area of the plane where reflectivity is often strong is in engine bay cavities, which tend to become resonant chambers when illuminated by radar. Dipoles installed in an engine bay cavity interact with the radar energy and disperse the energy. When properly positioned in the cavity, the dipoles defocus, or scatter, the energy at various angles, thus reducing the RCS of the cavity.
Carbon-carbon porous foam see Chapter 5 is a form of RAM used in engine bay cavities and is just as effective as dipoles in 28 attenuating or dissipating radar energy. Advanced Stealth Design Considerations and Operational Techniques O 29 Sharp external airframe angles are also good reflectors of radar energy, but CAD make it possible to reduce RCS by designing an airframe that tends to scatter and disperse radar energy instead of reflecting it back to the radar receiver FlGS.
Recent stealth designs from Lockheed include small flat techniques surfaces with high aspect angles to the radar illumination; these surfaces are excellent side-lobe attenuators. The radar like reflection of porcupine to the radar to quills, using from been designed stealth technology. RAM coatings, the F screens, but only be detected— reportedly, Aircraft that haven't benefit Lockheed's FA stealth fighter on radar and F RCS at when 20 miles or is said to look fuzzy, the aircraft is close enough less.
The tracking radars in the F and F were not able to lock on to the SR The effectiveness of the SR's stealth of tests, in While the goal of stealth technology is to make aircraft "invisible," in certain cases a stealth aircraft can be readily visible to radar. Older low-frequency early warning radars have wavelengths large enough to resolve stealth-equipped aircraft.
A flat Reflected radar echo surface at a right angle to incoming radar energy makes an excellent radar reflector detectable. It has a high radar signature. The paint highly infrared reflective and diffuses sunlight, thus helping the aircraft blend more easily into the background. Air Force Fig. The Air Force's B-1B bomber. Engine baffles that nacelles, the square portions under each wing, are fitted with snake-type hide the engine's metal compressor faces from incoming radar energy.
Triangular titanium radar reflectors Al to A4 are set at an angle to incoming radar energy. Super-plastic developed by Lockheed is fitted into the cavities formed by the titanium triangles Bl to B5. Radar reflector plates C deflect incoming radar energy D and keep it trapped in radar-absorbent plastic B. Tracking and guidance radars, for instance, can't distinguish between reflected radar signals from stealth aircraft and the signal from background as when is being used in look-down mode Fig.
With- out the necessary computing power, the low-tech radar cope would be blank and would not show any information on the stealth aircraft. However, on missions against countries that use an older low-frequency radar, a stealth aircraft might need to use other methods to avoid detection, or, as the saying goes, "If you can't be stealthy, then be sneaky.
Passive microwave or laser radar over tile hills is used to provide terrain-clearance information hug the ground as it streaks toward its target— climbing and mountains and dropping quickly into valleys— to remain clear of hos- for the aircraft, allowing it to radar searches.
Aircraft operating at high speeds close to the ground are equipped with autostabilization and automatic ride-control devices to smooth the often violently rough ride at such low altitudes. A stealth aircraft, on the other hand, with an RCS smaller than the wavelength of the interceptor's look-down radar and the ground-based early-warning radar and flying at low levels, could easily avoid detection.
The optimum time for low-level Conventional aircraft flying at quite successfully, but stealth operations is at night, preferably after midnight. AAAM development will use "new engage stealth-type targets. This technology apparently incorporates a breakthrough in sensor and signal processing systems.
The U. This is referred to as A, while aircraft D O 35 avoids radar nap-of-the-earth flying, terrain following, or jinking, and requires that the aircraft be flown at high speeds close to the ground to avoid detection. Although a RCS, its stealth aircraft might be able chances of completing its to avoid detection by radar merely by virtue of mission increase greatly if it bottom illustration shows a terrain-following aircraft and the path Most such flying is done within feet of the ground.
The might take around some obstacles. Friendly fighters also get information on intruders from Fig. An airborne radar detection system such as that used in the Sentinel can easily detect conventional attacking aircraft, even if they are flying low in an attempt to avoid detection by ground-based radars. If the Soviets deploy more advanced systems and newer radar and detection tracking equipment, then American stealth designers will need to develop new techniques to counter increasingly sophisticated Soviet systems.
The lower the stealth aircraft's RCS, the less power will be needed by the ECM equipment to jam burn through and spoof fool the hostile radar. The less radar energy reflected by the aircraft, the less power will be needed to alter the energy to fool the hostile radar. By the time it, cross-match it the radar operator notes the information miles away from where on his scope, the stealth aircraft will be many the operator believes the aircraft to be.
Over-the-horizon backscatter radar can detect targets over the horizon by bouncing radar energy off the iono- sphere. If a stealth aircraft is having trouble avoiding detection, the EFA Raven radar-jamming Raven is shown positioned for refueling by an The Raven can defeat any known Soviet radar used to direct surface-to-air missiles also effective against Soviet guidance radars. Air Force be helpful. This Great Britain. Used in conjunction with the FAG provides friendly aircraft an almost weapons-free path to and from intended targets by attacking EF- A Haven, the SAM sites with a variety of air-to-surface weapons.
Operating in conjunction with the F-4G and the EFA, a stealth aircraft could attack targets without suffering any damage.
Air Force Previously, there was some circumstantial evidence that the Soviets were own stealth program, U. One of the U. Radars capable of searching through the full radio-frequency spectrum can overcome some types of RAM by using a frequency that isn't addressed by the RAM. Their anti-aircraft missiles monopulse semiactive radar guidance, and some newer missiles use active radar guidance in the pulse-Doppler mode. Their surface-to-air missiles SAMs operate in Tband frequencies. These represent the threats that the U.
Millimeter- Wave Radiometry One possible countermeasure— a system that could be used to detect stealth measurement of radiation in the infrared, visible, and ultraviolet regions of the electromagnetic spectrum. This kind of system has sensors that can detect objects reflected against a background with a higher or lower temperature than the object.
A stealth aircraft might show warm against a cold sky as viewed from below, for instance, or cold against the warm earth as viewed from above. Thermal Imaging Sensor Closely akin to an infrared optical sensor is a new type called a thermal imaging which can sense both hot and cool areas of any given target, whether it be of conventional or stealth design. Unlike an infrared sensor, however, the TIS can "see" through mist, smoke, darkness, haze, light fog, and rain, and is not affected by low-level background ER radiation, which has hampered most IR sensors seeking targets, especially in the look-down mode.
The thermal imaging sensor better than infrared sensors. There is a down side to effectively employing thermal imaging sensors to detect ground-based targets. Targets to be hidden from the thermal sensor can employ a number of countermeasures, such as: O O Thermal sensors can be "spoofed" by decoys or blinded by false signals. Thermal imaging sensors can be spoofed by a British-developed antithermal smoke screen.
Called Visual and Infrared Screening Smoke V1RSS , it employs a substance to provide infrared "hotspots" within the smoke itself, as well as provide an absorbent quality. VIRSS reportedly can provide protection 3- to 5- and 8- to micron range. This netting screens and only allows undetectable warm air to be employ another emitted. In conjunction with this camouflaging, the item might thermal net to emit an infrared signature that matches the surrounding infrared background.
Whether or not makes use stealth aircraft being detected by thermal imaging sensors of these, or similar, techniques to avoid is not known. Radio-Frequency Sensor A sensor that employs methods developed for radio astronomy could be used Such sensors would be based on the principle that an object that gives off infrared radiation produces a corresponding radio signal.
It is the same principle that allows astronomers to learn the temperatures of stars and planets. A stealth aircraft flying through the air would not be able to avoid aerodynamic heating of the air it passes through, and thus would emit radio signals that could be picked up by a sensitive passive sensor. In this kind of sensor, signal-to-noise ratio is very important and will need to be at low enough levels for the sensor to detect radiofrequency emission produced by aerodynamic heating of an aircraft in flight.
Although these radio frequency emissions are relatively small compared to background noise, this type of sensor might be viable, given enough research and development. Bistatic Radar A bistatic radar transmits radar energy that is reflected from a target and received by receivers in locations apart from the transmitter.
These are passive receivers that aircraft, and that can guide weapons against stealth can be located on land, ships, or targets without being detected. Magnetic Anomaly Detector To track stealth aircraft, a magnetic anomaly detector MAD would have to be more sophisticated than the types used to detect submarines. MADs are used to show the position of submarines by detecting distortions in the Earth's magnetic field by the submarines' steel hulls.
Aluminum and its alloys distort the Earth's magnetic field much less than does the steel in submarines, but a sensitive enough MAD might be able to reveal the location of a stealth aircraft.
Doppler Radar Engineers speculate that, since by high-definition Doppler a stealth aircraft. The technique involves of radar energy simultaneously in frequencies is said to defeat certain types a radar that generates pulses spanning the entire or almost radar more advanced than the latest pulse Doppler, or frequency agile types, which might employ many different frequencies in operation, but only one frequency at a time.
The carrier-free radar, with its omni-frequency capability, has waves that are square to rectangular in form and will not be absorbed by RAMs. The carrier-free radar waves, therefore, will be reflected.
In most stealth aircraft designs, the precision fitting of parts of RAMs is very spectrum. This type of radar crucial to the aircraft's RCS is value. If the parts are not fitted to extremely close and will increase the RCS value CAD and computer-aided manufacturing CAM techniques were employed in the design and production of the B-2 and F stealth aircraft.
One technique employed by Lockheed for producing the F stealth fighter is called faceting and achieves excellent results at eliminating tolerances, radar reflective "hot-spots" will result of the stealth aircraft. Computer-aided-design the so-called radar reflective "hot-spots. With the recent advances in composite nonmetallic materials, stealth technology has become more viable and realistic. Some of the materials used in stealth aircraft include pure composites, composites combined with metal, coated metal, synthetic materials, glass fibers embedded in plastic, ceramic materials, and special paints and dissipating, RAM coatings.
Stealth technology has been driven by military needs, specifically by the U. Although materials for stealth aircraft certainly can be used for ordinary commercial or military aircraft, the pressing need for undetectable stealth aircraft has stimulated a great deal of research on materials that are suitable for stealth aircraft. This material was somewhat effective, but primitive and heavy. Too many 43 44 O Stealth Materials coats added too much weight to an aircraft, and in some cases, the treated aircraft became too heavy to fly.
Lockheed and Northrop were heavily involved with early stealth programs and gained considerable experience in the field. The two companies' prototypes also gained much press attention between and Boeing, Rockwell, General Dynamics, and LTV are also believed to have built stealth prototypes, including both flight and static, or wind tunnel test, articles.
Crucial Composites Composite materials are structures, leading to lighter now beginning to replace metal throughout aircraft airframes. A side benefit of composite and stronger is that they contribute greatly to reducing an aircraft's RCS and its infrared and acoustic signatures. Materials for stealth aircraft are chosen for their ability to absorb and dissipate microwave radar or infrared radiation.
Composites of carbon, boron, silicon, and materials such as ceramics and super-plastics are excellent radar materials energy absorbers. One Jaumann absorber, consists of laminated layers of a comby a dielectric spacer material.
Jaumann absorber is reportedly difficult to manufacture, but it has been developed to the point where it can be used with a reasonable degree of accuracy and effectiveness.
Note that any substance or material that absorbs energy will show an increase in temperature as a result of the energy absorption. Aluminum Oxide Fibers. Used in metal-matrix or hybrid composites with layer that an aramid is transparent to the radar energy. Aramid Fibers. Aromatic polyamide fibers used in resin-matrix composites. Large-diameter boron fibers for use in matrix resin and metal matrix composites can be made by vapor deposition of boron on tungsten filaments. Boron fibers can be coated with boron carbide for use in metal matrix composites.
Dense carbon grain and ultradense carbon foam pure pitch are used in engine areas to absorb heat from the engine exhaust. Carbon-carbon composites can be formed into wing leadingedge panels, and nose and tail cones. Carbon-reinforced Fiberglas material, developed by the Air Force, is used in some air-launched cruise missiles.
Carbon Fibers. Made from pitch for use in resin-matrix composites. Excellent radar-energy transparent material, making it an ideal Carbon-carbon Composite. Used infrared radiation dissipation dielectric substance. Also acts effectively as an infrared radiation dissipater when Early Developments Fibaloy. Developed by Dow O 45 Chemical Co. This material reportedly and which is skin for piloted vehicles RPVs that energy absorbency Lockheed manufactures.
Fibaloy has excellent radar- qualities. Epoxy Resin Composites. Simplest radar-energy transparent masome stealth aircraft and in many commerical aircraft. Fiberglas terial; used in A Du Pont product; possible replacement for carbon-fiber is an aramid fiber-based composite that is stronger and lighter than some metals and an excellent radar energy absorber. A commercial version of Kevlar also absorbs radar energy and is damage-resistant to gunfire.
Metals that will most likely be used in stealth airframes include a lightweight lithium-aluminum alloy, high-temperature aluminum-metal matrix composites, and to replace expensive titanium in areas where temperatures rise above degrees centigrade, a powder metallurgy aluminum-iron-cerium alloy. A metal -composite produced by Arco Metals Co. Rice hulls are baked at high temperatures until they break down into carbon and silicon-carbide whiskers.
These whiskers are mixed with aluminum powder to form Silag composite. Silag can be used for an aircraft's structural members. Radar-absorbent capabilities of Silag are Kevlar Kevlar 49 minimal, but the material is effective for Silicon-Carbide Fibers.
A silicon some specific radar wavelengths. Similar to tiles used on belly and wing leading edges of U. Silicon-carbide fibers are also used in metal-matrix composites.
Developed by Allied Corp. Developed by the Air Force Materials Laboratory and commercial firms, super-plastics are thermoplastics that are lighter and stronger than steel is of and titanium, but do not thought to reflect radar energy.
One application of thermoplastics be a black fiber-reinforced graphite skin used for the wing leading edges Northrop 's B-2A Advanced Technology Bomber. One class of thermoplastics is known as ordered polymers the Air Force Materials Laboratory. There are three and was developed by known types of ordered polymers: parapolybenzothiazole; parapolybenzoxazole; and parapolybenzimidazole.
The first has the greatest microwave-absorbency potential of the three. Boeing has developed a thermoplastic material for its part in the technology fighter ATF program. The company built a full-scale, advanced- high-temperature wing reinforced with graphite fibers to demonstrate advanced on Lockheed's YF ATF. Boeing is responsible for manufacturing YF primary and secondary structural members using thermoplastics. Operationally the YF aircraft will be easier to maintain because thermoplastics are tougher than thermoset composites is that thermoplastics and are easier to repair.
As a result, there airframe weight is Thermoplastic is more room Another advantage ratios nearly three times smaller is needed than to construct thermoplastic for fuel tanks or avionics installations and total reduced. Unlike thermoset composites, thermoplastic materials up and scrap can be down at degrees centigrade and reformed into new Compound curves, such as those needed in conformal engine air intakes reprocessed by being melted rigid parts. Like thermoset composites, thermoplastic parts are cured at a high temperature and high pressure in an autoclave.
Although thermoset composites were once widely considered the wave of the shown that they aren't used to make thermoset future, production experience, according to the Air Force, has as inexpensive as was once thought. The raw materials composites are more expensive than expected, and manufacturing costs and scrap rates are high. The advent of thermoplastics is resulting in new manufacturing processes, including automated hot-head tape-laying and postforming channels, that reduce times to build components to minutes instead of hours.
Thermoplastics also can be stored indefinitely at room temperature, as opposed to require special environmentally controlled storage. In addition to lower production costs, thermoplastics' ability to withstand higher temperatures means they will be well suited for construction of the supersonic— Mach 1.
Skin temperatures as much composites, but fighter at would be ATF's airframe will reach no problem for thermoplastic in certain areas of the as degrees centigrade. This presents those speeds and temperatures, a thermoset composite supersonic useless because thermosets become unstable above degrees centigrade.
Thermoplastics are more damage-resistant than thermoset composites, and any damage that occurs will be visible on the surface of the material. Thermoplastics will be used throughout the Lockheed YF, but metal will be used in areas where complex three-dimensional shapes and loading occur and, to ensure a wide margin of safety, where temperatures could rise above degrees centigrade. Thermoplastics are excellent radar-energy absorbers. They also can be such a way made in that they are transparent to radar energy.
Thermoset Composites. This material is made of high-strength carbon fibers in an epoxy resin FlG. It is like Fiberglas, but uses carbon fibers instead of glass fibers. Thermoset composites have a higher strength-to- weight ratio than metals, but it costs one and a half times as much to manufacture parts from thermoset composites instead of aluminum.
The material has a short shelf life and must be stored in controlled environment freezers. The strands are oxidized at 2, degrees Fahrenheit, leaving 97 percent pure carbon fiber, which can be woven into various shapes. Shown is a unidirectional carbon-fiber weave which is impregnated with epoxy, cut, then layered in varying orientations to make, in this case, a wing panel.
Thermoset composite must be cured in an autoclave, under high temperature and pressure. Once cured, the material has undergone an irreversible chemical reaction, unlike thermoplastic composites, can be cured, then reheated and reformed into Damage tolerance and toughness are new problems occurring with thermoset composites. Although carbon fibers are inherently strong, they are relatively weak and brittle resin. The paint is an effective radar-energy absorber, and radar operators on ships near the bridges can't see the bridges on their scopes, but can see other ships without the clutter from the bridges.
Department of Defense has tried ferrite-based coatings but although the paint did reduce the the aircraft too heavy to fly, aircraft's just as occurred on some made with MX in Research into and lightweight coatings continued, however, and advanced effective aircraft, radar signatures, the coating stealth paints now being used for a variety of military vehicles, including ships, tanks, and aircraft FlGS. The page itself is as much of a piece of art as the panels that reside in it a fan recently framed them.
The second reason for this is that the characters, ranging from comic strip icons like Snoopy to Popeye, lived on paper.
The madness that is this parody clicks better when you see these old and beloved characters murder the shit out of each-other on the dry and stark white paper that they were syndicated on for so long. Paper holds the concept better. Beyond the high quality of print, and the reasons that I believe you should read it as a physical copy, the author deserves your money.
Jason Yungbluth churns out quality work. So much of the internet is free, and so much of it is utter garbage. Weapon Brown is something the internet needs more of and frankly, should absolutely be valued in dollars. Confused about the entire concept of Weapon Brown? Your tags:. Send-to-Kindle or Email Please login to your account first Need help? Please read our short guide how to send a book to Kindle. The file will be sent to your email address.
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