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78-413: ATLAS-I was the largest NNEMP (non-nuclear electromagnetic pulse) generator in the world, designed to test the radiation hardening of strategic aircraft systems against EMP pulses from nuclear warfare . Built at a cost of $ 60 million, it was composed of two parts: a pair of powerful Marx generators capable of simulating the electromagnetic pulse effects of a high-altitude nuclear explosion (HANE) of

156-471: A Van de Graaff generator or other highly charged object, care must be taken to release the object and then discharge the body through a high resistance, in order to avoid the risk of a harmful shock pulse when stepping away. Very high electric field strengths can cause breakdown of the air and a potentially lethal arc current similar to lightning to flow, but electric field strengths of up to 200 kV/m are regarded as safe. According to research from Edd Gent,

234-481: A lightning strike can physically damage objects such as buildings and aircraft. The management of EMP effects is a branch of electromagnetic compatibility (EMC) engineering. The first recorded damage from an electromagnetic pulse came with the solar storm of August 1859, or the Carrington Event . In modern warfare, weapons delivering a high energy EMP are designed to disrupt communications equipment,

312-403: A transient electromagnetic disturbance ( TED ), is a brief burst of electromagnetic energy. The origin of an EMP can be natural or artificial, and can occur as an electromagnetic field , as an electric field , as a magnetic field , or as a conducted electric current . The electromagnetic interference caused by an EMP can disrupt communications and damage electronic equipment. An EMP such as

390-465: A 2016 article for the Tokyo -based nonprofit organization Center for Information and Security Trade Control, Onizuka warned that a high-altitude EMP attack would damage or destroy Japan 's power, communications and transport systems as well as disable banks, hospitals and nuclear power plants . Douglas fir The Douglas fir ( Pseudotsuga menziesii ) is an evergreen conifer species in

468-495: A 2019 report by the Electric Power Research Institute , which is funded by utility companies, found that a large EMP attack would probably cause regional blackouts but not a nationwide grid failure and that recovery times would be similar to those of other large-scale outages. It is not known how long these electrical blackouts would last, or what extent of damage would occur across the country. It

546-430: A common problem in the mid-twentieth century was interference emitted by the ignition systems of gasoline engines, which caused radio sets to crackle and TV sets to show stripes on the screen. CISPR 25 was established to set threshold standards that vehicles must meet for electromagnetic interference(EMI) emissions. At a high voltage level an EMP can induce a spark, for example from an electrostatic discharge when fuelling

624-530: A controlled EMP to wipe such magnetic media. A very large EMP event, such as a lightning strike or an air bursted nuclear weapon, is also capable of damaging objects such as trees, buildings and aircraft directly, either through heating effects or the disruptive effects of the very large magnetic field generated by the current. An indirect effect can be electrical fires caused by heating. Most engineered structures and systems require some form of protection against lightning to be designed in. A good means of protection

702-418: A corresponding signal in the surrounding environment or material. Coupling usually occurs most strongly over a relatively narrow frequency band, leading to a characteristic damped sine wave . Visually it is shown as a high frequency sine wave growing and decaying within the longer-lived envelope of the double-exponential curve. A damped sinewave typically has much lower energy and a narrower frequency spread than

780-565: A gasoline-engined vehicle. Such sparks have been known to cause fuel-air explosions and precautions must be taken to prevent them. A large and energetic EMP can induce high currents and voltages in the victim unit, temporarily disrupting its function or even permanently damaging it. A powerful EMP can also directly affect magnetic materials and corrupt the data stored on media such as magnetic tape and computer hard drives . Hard drives are usually shielded by heavy metal casings. Some IT asset disposal service providers and computer recyclers use

858-506: A large low-inductance capacitor bank discharged into a single-loop antenna, a microwave generator, and an explosively pumped flux compression generator . To achieve the frequency characteristics of the pulse needed for optimal coupling into the target, wave -shaping circuits or microwave generators are added between the pulse source and the antenna . Vircators are vacuum tubes that are particularly suitable for microwave conversion of high-energy pulses. NNEMP generators can be carried as

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936-434: A large number of state-of-the-art Tektronix 7912AD digitizers along with a large array of Digital Equipment Corporation PDP-11 computers. The pulse monitoring instrumentation consisted of a number of B dot and H field sensors mounted on the exterior of the wedge connected to oscilloscopes fitted with Polaroid cameras to capture the transient pulse data. The open-air third floor held large inflatable gas bags which could store

1014-452: A model is typically described either in a diagram or as a mathematical equation. Most electromagnetic pulses have a very sharp leading edge, building up quickly to their maximum level. The classic model is a double-exponential curve which climbs steeply, quickly reaches a peak and then decays more slowly. However, pulses from a controlled switching circuit often approximate the form of a rectangular or "square" pulse. EMP events usually induce

1092-511: A natural depression spanning 600 feet across and 120 feet in depth, equivalent to a 12-story-tall building. A wooden ramp 400 feet long by 50 feet wide led to a test stand which itself measured 200 feet by 200 feet. A total of 6.5 million board-feet of lumber were used to build the structure, sufficient to support a fully loaded B-52 (then the largest and heaviest strategic bomber in the US inventory) while also minimizing any chance of interference from

1170-549: A number of specifications including kiln dried and grade stamped, and can be supplied in very long lengths to 60 feet. West coast mills are sophisticated in their processing of timbers, making lead times predictable and availability reliable. Paints adhere well to Douglas fir. Stains perform well on Douglas fir timbers with the mild caution that the natural color of this species varies and care must be taken to ensure uniformity of color. Pitch pockets that may ooze resin can be present in timbers that have not been kiln dried. Because of

1248-569: A payload of bombs, cruise missiles (such as the CHAMP missile) and drones , with diminished mechanical, thermal and ionizing radiation effects, but without the consequences of deploying nuclear weapons. The range of NNEMP weapons is much less than nuclear EMP. Nearly all NNEMP devices used as weapons require chemical explosives as their initial energy source, producing only one millionth the energy of nuclear explosives of similar weight. The electromagnetic pulse from NNEMP weapons must come from within

1326-540: A specialized version of a Marx generator . Examples include the huge wooden-structured ATLAS-I simulator (also known as TRESTLE) at Sandia National Labs , New Mexico, which was at one time the world's largest EMP simulator. Papers on this and other large EMP simulators used by the United States during the latter part of the Cold War , along with more general information about electromagnetic pulses, are now in

1404-531: A tall wooden tower at the far end of the platform. The result was a fast 200 gigawatt pulse of electromagnetic flux powerful enough to reliably reproduce (at short range) the deleterious effects of a thermonuclear detonation on electronic circuitry as created by such examples as the HARDTACK I , ARGUS and DOMINIC I ( Operation Fishbowl ) high altitude nuclear tests. Due to their higher flight altitude and nuclear payload , Strategic Air Command bombers were

1482-456: Is a Faraday shield designed to protect certain items from being destroyed. Like any electromagnetic interference , the threat from EMP is subject to control measures. This is true whether the threat is natural or man-made. Therefore, most control measures focus on the susceptibility of equipment to EMP effects, and hardening or protecting it from harm. Man-made sources, other than weapons, are also subject to control measures in order to limit

1560-455: Is a significant component. The red vole nests almost exclusively in the foliage of the trees, typically 2–50 metres (5–165 ft) above the ground, and its diet consists chiefly of Douglas-fir needles. Douglas-fir needles are generally poor browse for ungulates , although in the winter when other food sources are lacking it can become important, and black-tailed deer browse new seedlings and saplings in spring and summer. The spring diet of

1638-712: Is considered to be an invasive species, called a wilding conifer , and is subject to control measures. But is also one of the most common lumber trees used in forestry alongside Radiata pine with large plantations throughout the country. The species was introduced in the 1900s for its wood. Douglas-fir prefers acidic or neutral soils. However, it exhibits considerable morphological plasticity, and on drier sites P. menziesii var. menziesii will generate deeper taproots. Pseudotsuga menziesii var. glauca exhibits even greater plasticity, occurring in stands of interior temperate rainforest in British Columbia, as well as at

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1716-516: Is extensively used in forestry management as a plantation tree for softwood timber . Douglas-fir is one of the world's best timber-producing species and yields more timber than any other species in North America, making the forestlands of western Oregon, Washington, and British Columbia the most productive on the continent. In 2011, Douglas-fir represented 34.2% of US lumber exports, to a total of 1.053 billion board-feet. Douglas fir timber

1794-843: Is found in the Klamath and California Coast Ranges as far south as the Santa Lucia Range , with a small stand as far south as the Purisima Hills in Santa Barbara County. One of the last remaining old growth stands of conifers is in the Mattole Watershed, and is under threat of logging. In the Sierra Nevada , it ranges as far south as the Yosemite region. It occurs from sea level along

1872-413: Is misleading since it is not a true fir, i.e., not a member of the genus Abies . For this reason, the name is often written as Douglas-fir (a name also used for the genus Pseudotsuga as a whole). The specific epithet menziesii is after Archibald Menzies , a Scottish physician and rival naturalist to David Douglas. Menzies first documented the tree on Vancouver Island in 1791. Colloquially,

1950-555: Is more shade tolerant than some associated fire-dependent species, such as western larch and ponderosa pine, and often replaces these species further inland. Fungal diseases such as laminated root rot and shoestring root-rot can cause significant damage, and in plantation settings dominated by Douglas-fir monocultures may cause extreme damage to vast swathes of trees. Interplanting with resistant or nonhost species such as western redcedar and beaked hazelnut can reduce this risk. Other threats to Douglas-fir include red ring rot and

2028-533: Is not a true fir ( genus Abies ), spruce (genus Picea ), or pine (genus Pinus ). It is also not a hemlock ; the genus name Pseudotsuga means "false hemlock". Douglas-firs are medium-size to extremely large evergreen trees, 20–100 metres (70–330 feet) tall (although only coast Douglas-firs , reach heights near 100 m) and commonly reach 2.4 m (8 ft) in diameter, although trees with diameters of almost 5 metres (16 feet) exist. The largest coast Douglas-firs regularly live over 500 years, with

2106-682: Is possible that neighboring countries of the U.S. could also be affected by such an attack, depending on the targeted area and people. According to an article from Naureen Malik, with North Korea's increasingly successful missile and warhead tests in mind, Congress moved to renew funding for the Commission to Assess the Threat to the U.S. from Electromagnetic Pulse Attack as part of the National Defense Authorization Act . According to research from Yoshida Reiji, in

2184-486: Is the Douglas-fir dwarf mistletoe ( Arceuthobium douglasii ). Epiphytes such as crustose lichens and mosses are common sights on Douglas-firs. As it is only moderately shade tolerant , undisturbed Douglas-fir stands in humid areas will eventually give way to later successional, more shade-tolerant associates such as the western redcedar and western hemlock—though this process may take a thousand years or more. It

2262-461: Is to use a current clamp in reverse, to inject a range of damped sine wave signals into a cable connected to the equipment under test. The damped sine wave generator is able to reproduce the range of induced signals likely to occur. Sometimes the threat pulse itself is simulated in a repeatable way. The pulse may be reproduced at low energy in order to characterise the subject's response prior to damped sinewave injection, or at high energy to recreate

2340-443: Is unusual in that it typically has a preliminary "leader" discharge of low energy building up to the main pulse, which in turn may be followed at intervals by several smaller bursts. ESD events are characterized by high voltages of many kV, but small currents sometimes cause visible sparks. ESD is treated as a small, localized phenomenon, although technically a lightning flash is a very large ESD event. ESD can also be man-made, as in

2418-416: Is used for timber frame construction and timber trusses using traditional joinery, veneer , and flooring due to its strength, hardness and durability. As of 2024, the only wooden ships still currently in use by the U.S. Navy in conventional naval operations are Avenger-class minesweepers , made of Douglas-fir. Douglas fir sees wide use in heavy timber structures, as its wood is strong, available in

ATLAS-I - Misplaced Pages Continue

2496-602: Is usually small and the signal may be treated as "noise" or "interference". The switching off or "opening" of a circuit causes an abrupt change in the current flowing. This can in turn cause a large pulse in the electric field across the open contacts, causing arcing and damage. It is often necessary to incorporate design features to limit such effects. Electronic devices such as vacuum tubes or valves, transistors, and diodes can also switch on and off very quickly, causing similar issues. One-off pulses may be caused by solid-state switches and other devices used only occasionally. However,

2574-505: The Douglas-fir beetle . Many different Native American groups used the bark, resin, and needles to make herbal treatments for various diseases. Native Hawaiians built waʻa kaulua ( double-hulled canoes ) from coast Douglas-fir logs that had drifted ashore. The wood has historically been favored as firewood , especially from the coastal variety. In addition early settlers used Douglas fir for all forms of building construction, including floors, beams, and fine carving. The species

2652-548: The Lynn Valley Tree and the Nooksack Giant . The leaves are flat, soft, linear needles 2–4 centimetres ( 3 ⁄ 4 – 1 + 1 ⁄ 2  in) long, generally resembling those of the firs, occurring singly rather than in fascicles ; they completely encircle the branches, which can be useful in recognizing the species. As the trees grow taller in denser forest, they lose their lower branches, such that

2730-550: The Umpqua River in Oregon. It is most dominant in areas with a more frequent fire regime that suppresses less fire-resistant conifers. Douglas-fir seeds are an extremely important food source for small mammals such as moles , shrews , and chipmunks , which consume an estimated 65% of each annual seed crop. The Douglas squirrel harvests and hoards great quantities of Douglas-fir cones, and also consumes mature pollen cones,

2808-468: The blue grouse features Douglas-fir needles prominently. The leaves are also used by the woolly conifer aphid Adelges cooleyi ; this 0.5 mm-long sap -sucking insect is conspicuous on the undersides of the leaves by the small white "fluff spots" of protective wax that it produces. It is often present in large numbers, and can cause the foliage to turn yellowish from the damage it causes. Exceptionally, trees may be partially defoliated by it, but

2886-507: The sulfur hexafluoride (SF 6 ) gas from the Marx generator enclosures when they needed to be opened for maintenance. The ATLAS-I program was shut down after the end of the Cold War in 1991, which brought an end to destructive EMP testing of aircraft by the Air Force, being replaced by far cheaper computer simulations as technology improved. Despite going without maintenance 20 years,

2964-532: The Earth's surface. The explosion releases a blast of gamma rays into the mid- stratosphere , which ionizes as a secondary effect and the resultant energetic free electrons interact with the Earth's magnetic field to produce a much stronger EMP than is normally produced in the denser air at lower altitudes. Non-nuclear electromagnetic pulse (NNEMP) is a weapon-generated electromagnetic pulse without use of nuclear technology. Devices that can achieve this objective include

3042-588: The Mexican border, becoming increasingly disjunct as latitude decreases and altitude increases. Mexican Douglas-fir ( P. lindleyana ), which ranges as far south as Oaxaca , is often considered a variety of P. menziesii . Fossils (wood, pollen) of Pseudotsuga are recorded from the Miocene and Pliocene of Europe ( Siebengebirge , Gleiwitz , Austria). It is also naturalised throughout Europe, Argentina and Chile (called Pino Oregón ). In New Zealand it

3120-501: The actual threat conditions. A small-scale ESD simulator may be hand-held. Bench- or room-sized simulators come in a range of designs, depending on the type and level of threat to be generated. At the top end of the scale, large outdoor test facilities incorporating high-energy EMP simulators have been built by several countries. The largest facilities are able to test whole vehicles including ships and aircraft for their susceptibility to EMP. Nearly all of these large EMP simulators used

3198-421: The aircraft to safely discharge any static. The switching action of an electrical circuit creates a sharp change in the flow of electricity. This sharp change is a form of EMP. Simple electrical sources include inductive loads such as relays, solenoids, and brush contacts in electric motors. These typically send a pulse down any electrical connections present, as well as radiating a pulse of energy. The amplitude

ATLAS-I - Misplaced Pages Continue

3276-436: The amount of pulse energy emitted. The discipline of ensuring correct equipment operation in the presence of EMP and other RF threats is known as electromagnetic compatibility (EMC). To test the effects of EMP on engineered systems and equipment, an EMP simulator may be used. Induced pulses are of much lower energy than threat pulses and so are more practicable to create, but they are less predictable. A common test technique

3354-411: The back half of a mouse, with two feet and a tail. The massive mega- genome of Douglas fir was sequenced in 2017 by the large PineRefSeq consortium, revealing a specialized photosynthetic apparatus in the light-harvesting complex of genes. The common name honors David Douglas , a Scottish botanist and collector who first reported the extraordinary nature and potential of the species. The common name

3432-652: The care of the SUMMA Foundation, which is hosted at the University of New Mexico. The US Navy also has a large facility called the Electro Magnetic Pulse Radiation Environmental Simulator for Ships I (EMPRESS I). High-level EMP signals can pose a threat to human safety. In such circumstances, direct contact with a live electrical conductor should be avoided. Where this occurs, such as when touching

3510-607: The coast to elevations of 1,500 m (4,900 ft) or higher, and inland in some cases up to 2,100 m (6,900 ft). Another variety exists further inland, Pseudotsuga menziesii var. glauca , the Rocky Mountain Douglas-fir or interior Douglas-fir. Interior Douglas-fir intergrades with coast Douglas-fir in the Cascades of northern Washington and southern British Columbia, and from there ranges northward to central British Columbia and southeastward to

3588-516: The computers needed to operate modern warplanes, or even put the entire electrical network of a target country out of commission. An electromagnetic pulse is a short surge of electromagnetic energy. Its short duration means that it will be spread over a range of frequencies. Pulses are typically characterized by: The frequency spectrum and the pulse waveform are interrelated via the Fourier transform which describes how component waveforms may sum to

3666-602: The damage is rarely this severe. Among Lepidoptera , apart from some that feed on Pseudotsuga in general, the gelechiid moths Chionodes abella and C. periculella as well as the cone scale-eating tortrix moth Cydia illutana have been recorded specifically on P. menziesii . The inner bark is the primary winter food for the North American porcupine . Poriol is a flavanone, a type of flavonoid, produced by P. menziesii in reaction to infection by Poria weirii . A parasitic plant which uses P. menziesii

3744-960: The edge of semi-arid sagebrush steppe throughout much of its range, where it generates even deeper taproots still. The coast Douglas-fir variety is the dominant tree west of the Cascade Mountains in the Pacific Northwest . It occurs in nearly all forest types and competes well on most parent materials, aspects, and slopes. Adapted to a more moist, mild climate than the interior subspecies, it grows larger and faster than Rocky Mountain Douglas-fir. Associated trees include western hemlock , Sitka spruce , sugar pine , western white pine , ponderosa pine , grand fir , coast redwood , western redcedar , California incense-cedar , Lawson's cypress , tanoak , bigleaf maple and several others. Pure stands are also common, particularly north of

3822-481: The electric and the magnetic field components have a discontinuity. In general, only radiation acts over long distances, with the magnetic and electric fields acting over short distances. There are a few exceptions, such as a solar magnetic flare . A pulse of electromagnetic energy typically comprises many frequencies from very low to some upper limit depending on the source. The range defined as EMP, sometimes referred to as "DC [direct current] to daylight", excludes

3900-503: The explosively pumped flux compression generator for generating a non-nuclear electromagnetic pulse was conceived as early as 1951 by Andrei Sakharov in the Soviet Union, but nations kept work on non-nuclear EMP classified until similar ideas emerged in other nations. Minor EMP events, and especially pulse trains, cause low levels of electrical noise or interference which can affect the operation of susceptible devices. For example,

3978-406: The extensive fire suppression piping were constructed of fiberglass . On the other side of the platform was the transmission "wedge", 250 feet in length with a total height of 240 feet. The wedge was constructed using steel I-beams. The entire structure was covered with a wire mesh similar to livestock fencing in order to create an enormous Faraday cage. A multistory building was constructed inside

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4056-423: The foliage may start as high as 34 m (110 ft) off the ground. Douglas-firs in environments with more light may have branches much closer to the ground. The bark on young trees is thin, smooth, grey, and contains numerous resin blisters. On mature trees, usually exceeding 80 years, it is very thick and corky, growing up to 36 cm (14 in) thick with distinctive, deep vertical fissures caused by

4134-858: The funding necessary to have the structure protected as a national historic landmark , although efforts are complicated by the top secret nature of the Sandia/Kirtland facility. The trestle structure is visible from commercial aircraft landing and taking off from Albuquerque International Sunport , lying about one mile to the southeast of the threshold of Runway 26 at 35°01′47″N 106°33′28″W  /  35.02981109416866°N 106.55767558197573°W  / 35.02981109416866; -106.55767558197573 . 35°01′48″N 106°33′27″W  /  35.029898°N 106.557574°W  / 35.029898; -106.557574  ( ATLAS-I (Trestle) ) NNEMP#Non-nuclear electromagnetic pulse An electromagnetic pulse ( EMP ), also referred to as

4212-569: The gradual expansion of the growing tree. Some of the mature bark is brown, while other parts are lighter colored with a cork-like texture; these develop in multiple layers. This thick bark makes the Douglas-fir one of the most fire-resistant tree native to the Pacific Northwest. The female cones are pendulous, with persistent scales, unlike those of true firs. They have distinctive long, trifid (three-pointed) bracts which protrude prominently above each scale and are said to resemble

4290-412: The ground or the structure itself, creating a reasonable simulation of airborne conditions. A mix of Douglas fir and Southern yellow pine were used for the timbers, as both showed excellent EMP transparency with the former having the best tensile strength and the latter the best weather resistance. By using an all glued laminated timber structure and woodworking joints to mate the giant timbers, with

4368-561: The highest frequencies comprising the optical ( infrared , visible , ultraviolet ) and ionizing ( X and gamma rays ) ranges. Some types of EMP events can leave an optical trail, such as lightning and sparks, but these are side effects of the current flow through the air and are not part of the EMP itself. The waveform of a pulse describes how its instantaneous amplitude (field strength or current) changes over time. Real pulses tend to be quite complicated, so simplified models are often used. Such

4446-419: The inner bark, terminal shoots, and developing young needles. Mature or "old-growth" Douglas-fir forest is the primary habitat of the red tree vole ( Arborimus longicaudus ) and the spotted owl ( Strix occidentalis ). Home range requirements for breeding pairs of spotted owls are at least 400 hectares (4.0 km ; 990 acres) of old growth. Red tree voles may also be found in immature forests if Douglas-fir

4524-399: The joints being held together with wooden bolts and nuts, measurements from the EMP tests would not be skewed by large amounts of ferrous material in the structure. Some metal was used in the construction as critically loaded joints incorporated a circular steel shear ring that surrounded the wooden bolt clamping the joint. Even the fire escape along one side of the trestle and the whole of

4602-504: The many millions of transistors in a modern computer may switch repeatedly at frequencies above 1  GHz, causing interference that appears to be continuous. A nuclear electromagnetic pulse is the abrupt pulse of electromagnetic radiation resulting from a nuclear explosion . The resulting rapidly changing electric fields and magnetic fields may couple with electrical/electronic systems to produce damaging current and voltage surges . The intense gamma radiation emitted can also ionize

4680-425: The observed frequency spectrum. EMP energy may be transferred in any of four forms: According to Maxwell's equations , a pulse of electric energy will always be accompanied by a pulse of magnetic energy. In a typical pulse, either the electric or the magnetic form will dominate. It can be shown that the non-linear Maxwell's equations can have time-dependent self-similar electromagnetic shock wave solutions where

4758-468: The oldest specimens living for over 1,300 years. Rocky Mountain Douglas-firs , found further to the east, are less long-lived, usually not exceeding 400 years in age. There are records of former coast Douglas-firs exceeding 120 metres (390 feet) in height, which if alive today would make it the tallest tree species on Earth. Particular historical specimens with heights exceeding 400 feet include

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4836-415: The operation of Trestle greatly assisted in the construction of the much more powerful 40 megavolt, 50 terawatt (50,000 gigawatt) Z Machine at Sandia during the 1990s. Technological advances during the 2000s have since boosted this output to 290 terawatts (290,000 gigawatts), high enough to actually study nuclear fusion at the point of detonation. The primary wooden structure of trestle was built inside

4914-441: The original pulse, due to the transfer characteristic of the coupling mode. In practice, EMP test equipment often injects these damped sinewaves directly rather than attempting to recreate the high-energy threat pulses. In a pulse train, such as from a digital clock circuit, the waveform is repeated at regular intervals. A single complete pulse cycle is sufficient to characterise such a regular, repetitive train. An EMP arises where

4992-403: The pine family, Pinaceae . It is native to western North America and is also known as Douglas-fir , Douglas spruce , Oregon pine , and Columbian pine . There are three varieties: coast Douglas-fir ( P. menziesii var. menziesii ), Rocky Mountain Douglas-fir ( P. menziesii var. glauca ) and Mexican Douglas-fir ( P. menziesii var. lindleyana ). Despite its common names , it

5070-506: The primary object of the tests, but fighters, transport aircraft and even missiles were also tested for EMP hardness on Trestle. In addition to electronics survivability tests, numerous sensors located inside, beneath and to the sides of the aircraft would gather additional data on the airframe's EMP permeability to be used in design considerations for future Cold War aircraft and to identify areas which needed additional EM hardening. The advances made in EMP generation technology by Sandia during

5148-401: The same manner as the main test platform, one on each side of a large wedge shaped steel structure which acted as a ground plane for the horizontally polarized pulse. Each Marx generator consisted of a stack of 50 trays, each containing two large capacitors and a plasma switch. A large peaking capacitor, used to adjust the shape of the resulting pulse, was also part of the design. Each generator

5226-400: The shock received from a Van de Graaff generator . An ESD event can damage electronic circuitry by injecting a high-voltage pulse, besides giving people an unpleasant shock. Such an ESD event can also create sparks, which may in turn ignite fires or fuel-vapour explosions. For this reason, before refueling an aircraft or exposing any fuel vapor to the air, the fuel nozzle is first connected to

5304-483: The source emits a short-duration pulse of energy. The energy is usually broadband by nature, although it often excites a relatively narrow-band damped sine wave response in the surrounding environment. Some types are generated as repetitive and regular pulse trains . Different types of EMP arise from natural, man-made, and weapons effects. Types of natural EMP events include: Types of (civil) man-made EMP events include: Types of military EMP include: Lightning

5382-472: The species is also known simply as Doug fir or Douglas pine (although the latter common name may also refer to Pinus douglasiana ). Other names for this tree have included Oregon pine , British Columbian pine , Puget Sound pine , Douglas spruce , false hemlock , red fir , or red pine (although again red pine may refer to a different tree species, Pinus resinosa , and red fir may refer to Abies magnifica ). One Coast Salish name for

5460-399: The surrounding air, creating a secondary EMP as the atoms of air first lose their electrons and then regain them. NEMP weapons are designed to maximize such EMP effects as the primary damage mechanism, and some are capable of destroying susceptible electronic equipment over a wide area. A high-altitude electromagnetic pulse (HEMP) weapon is a NEMP warhead designed to be detonated far above

5538-493: The timber sizes available, stamped timber grading, and relatively short lead times, Douglas fir sees wide use in both public and residential projects. The species has ornamental value in large parks and gardens. It has been commonly used as a Christmas tree since the 1920s, and the trees are typically grown on plantations. The buds have been used to flavor eau de vie , a clear, colorless fruit brandy. Douglas-fir pine leaves can be used to make pine needle tea . They possess

5616-705: The tree, used in the Halkomelem language, is lá:yelhp . In the Lushootseed language, the tree is called čəbidac . Pseudotsuga menziesii var. menziesii , the coast Douglas-fir, grows in the coastal regions from west-central British Columbia southward to central California . In Oregon and Washington , its range is continuous from the eastern edge of the Cascades west to the Pacific Coast Ranges and Pacific Ocean. In California, it

5694-527: The type expected during a nuclear war, and a giant wooden trestle built in a bowl-shaped arroyo , designed to elevate the test aircraft above ground interference and orient it below the pulse in a similar manner to what would be seen in mid-air. Trestle is the world's largest structure composed entirely of wood and glue laminate. The electromagnetic pulse was produced by a pair of Marx generators built by Maxwell Laboratories of San Diego, California. The generators were mounted on pedestals constructed of wood in

5772-423: The weapon, while nuclear weapons generate EMP as a secondary effect. These facts limit the range of NNEMP weapons, but allow finer target discrimination. The effect of small e-bombs has proven to be sufficient for certain terrorist or military operations. Examples of such operations include the destruction of electronic control systems critical to the operation of many ground vehicles and aircraft. The concept of

5850-420: The wedge were charged to opposite polarities and fired into twin transmission lines (antennas) mounted on either side of the test platform. When triggered simultaneously the resulting EM waves from each generator combined at the sharp point of the wedge building, adding to a total electrical potential of 10 mega volts . The transmission lines were terminated into a 50 ohm low inductance resistive load mounted on

5928-410: The wedge which served as offices, laboratories and testing facilities. The second floor of the building housed a large electromagnetically shielded room, supplied by Electromagnetic Filter Company of Palo Alto, California, which contained the data acquisition electronics, the Marx generator charging and firing control and field strength monitoring instrumentation. The data acquisition system consisted of

6006-414: The wooden trestle structures were all still standing in 2011, and the structure remained the biggest metal-free wood laminate structure in the world. The trestle had become a significant fire hazard since the pentachlorophenol - isobutane - ether -treated wood had dried considerably in the desert conditions and the automatic fire sprinkler system had been deactivated in 1991. Efforts were underway to secure

6084-442: Was enclosed in a large fiberglass structure which was filled with sulfur hexafluoride (SF 6 ) acting as an insulating gas. The tray capacitors were slowly charged such that each tray had up to 100kV of potential. When discharged through the plasma switches, the 50 trays in series could (ideally) produce up to 5 megavolts of electrical potential in a pulse with a rise-time in the 100 nanosecond range. The generators on either side of

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