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89-441: The three-stream adaptive cycle design can direct air to the bypass third stream for increased fuel efficiency and cooling or to the core and fan streams for additional thrust and performance. The 45,000 lbf (200 kN) thrust class engine is expected to be significantly more powerful and efficient than existing low-bypass turbofans. The U.S. Air Force and U.S. Navy began pursuing the adaptive cycle engine concept in 2007 with

178-403: A helicopter . The fuel economy of an automobile relates to the distance traveled by a vehicle and the amount of fuel consumed . Consumption can be expressed in terms of the volume of fuel to travel a distance, or the distance traveled per unit volume of fuel consumed. Since fuel consumption of vehicles is a significant factor in air pollution, and since the importation of motor fuel can be

267-617: A car and the production, transmission and storage of electricity and hydrogen, the label "zero pollution" applies only to the car's conversion of stored energy into movement. In 2004, a consortium of major auto-makers — BMW , General Motors , Honda , Toyota and Volkswagen / Audi — came up with "Top Tier Detergent Gasoline Standard" to gasoline brands in the US and Canada that meet their minimum standards for detergent content and do not contain metallic additives. Top Tier gasoline contains higher levels of detergent additives in order to prevent

356-399: A change in buying habits with a propensity to heavier vehicles that are less fuel-efficient. Energy efficiency is similar to fuel efficiency but the input is usually in units of energy such as megajoules (MJ), kilowatt-hours (kW·h), kilocalories (kcal) or British thermal units (BTU). The inverse of "energy efficiency" is " energy intensity ", or the amount of input energy required for

445-494: A common point) to focus sunlight on ships of the Roman fleet as they invaded Syracuse , setting them on fire. Historians point out that the earliest accounts of the battle did not mention a "burning mirror", but merely stated that Archimedes's ingenuity combined with a way to hurl fire were relevant to the victory. Some attempts to replicate this feat have had some success; in particular, an experiment by students at MIT showed that

534-461: A crowd are unaffected, except by panic when they see people fainting, being sick, or running from the scene with their hands over their ears. The virtual inaudibility of the equipment is said to produce a 'spooky' psychological effect." The UK's Ministry of Defence denied the existence of such a device. It stated that it did have, however, an "ultra-loud public address system which [...] could be 'used for verbal communication over two miles, or put out

623-486: A diesel engine. See Brake-specific fuel consumption for more information. The energy efficiency in transport is the useful travelled distance , of passengers, goods or any type of load; divided by the total energy put into the transport propulsion means. The energy input might be rendered in several different types depending on the type of propulsion, and normally such energy is presented in liquid fuels , electrical energy or food energy . The energy efficiency

712-469: A heat value of a fuel, it would be trivial to convert from fuel units (such as litres of gasoline) to energy units (such as MJ) and conversely. But there are two problems with comparisons made using energy units: The specific energy content of a fuel is the heat energy obtained when a certain quantity is burned (such as a gallon, litre, kilogram). It is sometimes called the heat of combustion . There exists two different values of specific heat energy for

801-467: A large part of a nation's foreign trade , many countries impose requirements for fuel economy. Different methods are used to approximate the actual performance of the vehicle. The energy in fuel is required to overcome various losses ( wind resistance , tire drag , and others) encountered while propelling the vehicle, and in providing power to vehicle systems such as ignition or air conditioning. Various strategies can be employed to reduce losses at each of

890-607: A mirror-based weapon was at least possible, if not necessarily practical. The hosts of MythBusters tackled the Mirrors of Archimedes three times (in episodes 19, 57 and 172 ) and were never able to make the target ship catch fire, declaring the myth busted three separate times. In 1935, the British Air Ministry asked Robert Watson-Watt of the Radio Research Station whether a " death ray "

979-467: A much slower rate and more efficiently than even a candle on Earth, and last much longer. Directed-energy weapon A directed-energy weapon ( DEW ) is a ranged weapon that damages its target with highly focused energy without a solid projectile, including lasers , microwaves , particle beams , and sound beams. Potential applications of this technology include weapons that target personnel , missiles , vehicles, and optical devices. In

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1068-487: A non-lethal directed-acoustic-energy weapon. LRAD systems are used for long-range communications in a variety of applications and as a means of non-lethal, non-projectile crowd control. They are also used on ships as an anti-piracy measure. According to the manufacturer's specifications, the systems weigh from 15 to 320 pounds (7 to 145 kg) and can emit sound in a 30°- 60° beam at 2.5 kHz. They range in size from small, portable handheld units which can be strapped to

1157-502: A number of countries still using other systems, fuel economy is expressed in miles per gallon (mpg), for example in the US and usually also in the UK ( imperial gallon); there is sometimes confusion as the imperial gallon is 20% larger than the US gallon so that mpg values are not directly comparable. Traditionally, litres per mil were used in Norway and Sweden , but both have aligned to

1246-404: A person's chest, to larger models which require a mount. The power of the sound beam which LRADs produce is sufficient to penetrate vehicles and buildings while retaining a high degree of fidelity, so that verbal messages can be conveyed clearly in some situations. According to a legend, Archimedes created a mirror with an adjustable focal length (or more likely, a series of mirrors focused on

1335-446: A senior US Air Force officer noted: "they aren't particularly suited to create weapons effects on missiles because of limited antenna size, power and field of view". Potentially lethal effects are produced only inside 100 meters range, and disruptive effects at distances on the order of one kilometer. Moreover, cheap countermeasures can be applied to existing missiles. A weapon often described as an "anti-drone rifle" or "anti-drone gun"

1424-403: A series of hydrogen fueling stations has been established. Powered either through chemical reactions in a fuel cell that create electricity to drive very efficient electrical motors or by directly burning hydrogen in a combustion engine (near identically to a natural gas vehicle , and similarly compatible with both natural gas and gasoline); these vehicles promise to have near-zero pollution from

1513-459: A small combustion engine is combined with electric motors. Kinetic energy which would otherwise be lost to heat during braking is recaptured as electrical power to improve fuel efficiency. The larger batteries in these vehicles power the car's electronics , allowing the engine to shut off and avoid prolonged idling . Fleet efficiency describes the average efficiency of a population of vehicles. Technological advances in efficiency may be offset by

1602-539: A sustained or modulated sound blanket to make conversation, and thus crowd organisation, impossible.'" In East Germany in the 1960s, in an effort to avoid international condemnation for arresting and interrogating people for holding politically incorrect views or for performing actions deemed hostile by the state the state security service, the Stasi , attempted alternative methods of repression which could paralyze people without imprisoning them. One such alternative method

1691-472: A unit of output such as MJ/passenger-km (of passenger transport), BTU/ton-mile or kJ/t-km (of freight transport), GJ/t (for production of steel and other materials), BTU/(kW·h) (for electricity generation), or litres/100 km (of vehicle travel). Litres per 100 km is also a measure of "energy intensity" where the input is measured by the amount of fuel and the output is measured by the distance travelled. For example: Fuel economy in automobiles . Given

1780-436: Is a battery-powered electromagnetic pulse weapon held to an operator's shoulder, pointed at a flying target in a way similar to a rifle , and operated. While not a rifle or gun, it is so nicknamed as it is handled in the same way as a personal rifle. The device emits separate electromagnetic pulses to suppress navigation and transmission channels used to operate an aerial drone , terminating the drone's contact with its operator;

1869-517: Is a popular topic in the field of artificial intelligence (AI) and machine learning (ML). The main factors representing and influencing driving behavior include velocity, acceleration, gear, road parameters, weather, etc. Simple things such as keeping tires properly inflated, having a vehicle well-maintained and avoiding idling can dramatically improve fuel efficiency. Careful use of acceleration and deceleration and especially limiting use of high speeds helps efficiency. The use of multiple such techniques

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1958-401: Is also occasionally known as energy intensity . The inverse of the energy efficiency in transport is the energy consumption in transport. Energy efficiency in transport is often described in terms of fuel consumption , fuel consumption being the reciprocal of fuel economy. Nonetheless, fuel consumption is linked with a means of propulsion which uses liquid fuels , whilst energy efficiency

2047-548: Is applicable to any sort of propulsion. To avoid said confusion, and to be able to compare the energy efficiency in any type of vehicle, experts tend to measure the energy in the International System of Units , i.e., joules . Therefore, in the International System of Units, the energy efficiency in transport is measured in terms of metre per joule, or m/J, while the energy consumption in transport

2136-485: Is called " hypermiling ". The most efficient machines for converting energy to rotary motion are electric motors, as used in electric vehicles . However, electricity is not a primary energy source so the efficiency of the electricity production has also to be taken into account. Railway trains can be powered using electricity, delivered through an additional running rail, overhead catenary system or by on-board generators used in diesel-electric locomotives as common on

2225-535: Is capable of engaging multiple targets, including drone swarms, and reportedly costs less than 10 pence (13 cents ) per shot, making it a cheaper alternative to traditional missile-based air defense systems. A laser weapon is a directed-energy weapon based on lasers . An example of a laser directed-energy weapon is the DragonFire currently being developed by the United Kingdom. It is reportedly in

2314-585: Is commonly defined as being between 300 MHz and 300 GHz (wavelengths of 1 meter to 1 millimeter), which is within the radiofrequency (RF) range. Some examples of weapons which have been publicized by the military are as follows: Active Denial System is a millimeter wave source that heats the water in a human target's skin and thus causes incapacitating pain. It was developed by the U.S. Air Force Research Laboratory and Raytheon for riot-control duty. Though intended to cause severe pain while leaving no lasting damage, concern has been voiced as to whether

2403-400: Is dependent on many parameters of a vehicle, including its engine parameters, aerodynamic drag , weight, AC usage, fuel and rolling resistance . There have been advances in all areas of vehicle design in recent decades. Fuel efficiency of vehicles can also be improved by careful maintenance and driving habits. Hybrid vehicles use two or more power sources for propulsion. In many designs,

2492-443: Is measured in terms of joules per metre, or J/m. The more efficient the vehicle, the more metres it covers with one joule (more efficiency), or the fewer joules it uses to travel over one metre (less consumption). The energy efficiency in transport largely varies by means of transport. Different types of transport range from some hundred kilojoules per kilometre (kJ/km) for a bicycle to tens of megajoules per kilometre (MJ/km) for

2581-533: Is not formed and complete combustion occurs., National Aeronautics and Space Administration, April 2005. Experiments by NASA in microgravity reveal that diffusion flames in microgravity allow more soot to be completely oxidised after they are produced than diffusion flames on Earth, because of a series of mechanisms that behaved differently in microgravity when compared to normal gravity conditions. LSP-1 experiment results , National Aeronautics and Space Administration, April 2005. Premixed flames in microgravity burn at

2670-503: Is not the right fit for the F-35.” Instead, Pratt & Whitney is proposing a "drop-in" enhanced engine package that would improve thrust and range by 10% while also offering a 50% improvement in thermal management. While this falls short of the AETP's goal of a 25% improvement in fuel efficiency, Pratt & Whitney argues the savings would be worth it, estimating the cost of developing AETP for

2759-434: Is very low. This was reflected in a study by AEA Technology between a Eurostar train and airline journeys between London and Paris, which showed the trains on average emitting 10 times less CO 2 , per passenger, than planes, helped in part by French nuclear generation. In the future, hydrogen cars may be commercially available. Toyota is test-marketing vehicles powered by hydrogen fuel cells in southern California, where

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2848-608: The Wunderwaffe . Among the directed-energy weapons the Nazis investigated were X-ray beam weapons developed under Heinz Schmellenmeier, Richard Gans and Fritz Houtermans. They built an electron accelerator called Rheotron to generate hard X-ray synchrotron beams for the Reichsluftfahrtministerium (RLM). Invented by Max Steenbeck at Siemens-Schuckert in the 1930s, these were later called Betatrons by

2937-490: The 1969 Sino-Soviet border clashes , though William Colby doubted that they had actually been employed. In 1973, New Scientist magazine reported that a sonic weapon known as a "squawk box" underwent successful field trials in Northern Ireland, using soldiers as guinea pigs. The device combined two slightly different frequencies which when heard would be heard as the sum of the two frequencies (ultrasonic) and

3026-469: The ALKA directed-energy weapon . After decades of research and development , most directed-energy weapons are still at the experimental stage and it remains to be seen if or when they will be deployed as practical, high-performance military weapons. Directed energy weapons could have several main advantages over conventional weaponry: Some devices are described as microwave weapons; the microwave frequency

3115-626: The Adaptive Versatile Engine Technology (ADVENT) program, a part of the larger Versatile Affordable Advanced Turbine Engines (VAATE) program. While not involved with ADVENT, Pratt & Whitney was selected alongside General Electric for the Adaptive Engine Technology Demonstrator (AETD) program that followed in 2012; this program continued to mature the technology, with tests performed using demonstrator engines. The next step,

3204-638: The Boeing YAL-1 and Boeing NC-135 , the first of which destroyed two missiles in February 2010. Funding has been cut to both of the programs. During the Iraq War , electromagnetic weapons, including high power microwaves, were used by the U.S. military to disrupt and destroy Iraqi electronic systems and may have been used for crowd control. Types and magnitudes of exposure to electromagnetic fields are unknown. The Soviet Union invested some effort in

3293-556: The EL/M-2080 Green Pine radar makes it a hypothetical candidate for conversion into a directed-energy weapon, by focusing pulses of radar energy on target missiles. The energy spikes are tailored to enter missiles through antennas or sensor apertures where they can fool guidance systems, scramble computer memories or even burn out sensitive electronic components. AESA radars mounted on fighter aircraft have been slated as directed energy weapons against missiles, however,

3382-531: The Haber process . In the context of transport , fuel economy is the energy efficiency of a particular vehicle, given as a ratio of distance traveled per unit of fuel consumed. It is dependent on several factors including engine efficiency , transmission design, and tire design. In most countries, using the metric system , fuel economy is stated as "fuel consumption" in liters per 100 kilometers (L/100 km) or kilometers per liter (km/L or kmpl). In

3471-708: The Shiva Star project (a high energy capacitor bank which provided the means to test weapons and other devices requiring brief and extremely large amounts of energy) to accelerate a toroid of plasma at a significant percentage of the speed of light. Additionally, the Russian Federation claims to be developing various plasma weapons. The Long Range Acoustic Device ( LRAD ) is an acoustic hailing device developed by Genasys (formerly LRAD Corporation) to send messages and warning tones over longer distances or at higher volume than normal loudspeakers , and as

3560-530: The heart , stomach and intestines .) Lung tissue was affected at only the closest ranges as atmospheric air is highly compressible and only the blood rich alveoli resist compression. In practice, the weapon was highly vulnerable to enemy fire. Rifle , bazooka and mortar rounds easily deformed the parabolic reflectors, rendering the wave amplification ineffective. In the later phases of World War II , Nazi Germany increasingly put its hopes on research into technologically revolutionary secret weapons,

3649-399: The latent heat of vaporization of water. The difference between the high and low values is significant, about 8 or 9%. This accounts for most of the apparent discrepancy in the heat value of gasoline. In the U.S. (and the table) the high heat values have traditionally been used, but in many other countries, the low heat values are commonly used. Neither the gross heat of combustion nor

Pratt & Whitney XA101 - Misplaced Pages Continue

3738-529: The ratio of effort to result of a process that converts chemical potential energy contained in a carrier ( fuel ) into kinetic energy or work . Overall fuel efficiency may vary per device, which in turn may vary per application, and this spectrum of variance is often illustrated as a continuous energy profile . Non-transportation applications, such as industry , benefit from increased fuel efficiency, especially fossil fuel power plants or industries dealing with combustion , such as ammonia production during

3827-604: The 1980s, with the participation of noted physicists including Edward Teller . A notable example of a directed energy system which came out of the SDI program is the Neutral Particle Beam Accelerator developed by Los Alamos National Laboratory . This system is officially described (on the Smithsonian Air and Space Museum website ) as a low power neutral particle beam (NPB) accelerator, which

3916-499: The 50 kW class and is capable of engaging any target within line-of-sight at a currently classified range. It has been tested against drones and mortar rounds and is expected to equip ships, aircraft and ground vehicles from 2027. Particle-beam weapons can use charged or neutral particles, and can be either endoatmospheric or exoatmospheric. Particle beams as beam weapons are theoretically possible, but practical weapons have not been demonstrated yet. Certain types of particle beams have

4005-700: The Adaptive Engine Transition Program (AETP), was launched in 2016 to develop adaptive engines for sixth-generation fighter propulsion as well as potential re-engining of the F-35 from the existing F135 turbofan engine. The General Electric demonstrator was designated XA100 and the P&;W engine was designated XA101. The AETP goal was to demonstrate 25% improved fuel efficiency, 10% additional thrust, and improved thermal management. In 2017, Pratt & Whitney successfully tested an adaptive three-stream fan with an F135 core, and considered

4094-745: The Americans. The intent was to pre-ionize ignition in aircraft engines and hence serve as anti-aircraft DEW and bring planes down into the reach of the flak. The Rheotron was captured by the Americans in Burggrub on April 14, 1945. Another approach was Ernst Schiebolds 'Röntgenkanone' developed from 1943 in Großostheim near Aschaffenburg . Richert Seifert & Co from Hamburg delivered parts. The Central Intelligence Agency informed Secretary Henry Kissinger that it had twelve reports of Soviet forces using laser weapons against Chinese forces during

4183-620: The Central Intelligence Agency issued an interim assessment concluding that the syndrome is not the result of "a sustained global campaign by a hostile power." Foreign involvement was ruled out in 976 cases of the 1,000 reviewed. In February 2022, the State Department released a report by the JASON Advisory Group, which stated that it was highly unlikely that a directed-energy attack had caused

4272-457: The EU standard of L/100 km. Fuel consumption is a more accurate measure of a vehicle's performance because it is a linear relationship while fuel economy leads to distortions in efficiency improvements. Weight-specific efficiency (efficiency per unit weight) may be stated for freight , and passenger-specific efficiency (vehicle efficiency per passenger) for passenger vehicles. Fuel efficiency

4361-482: The F-35 at up to $ 40 Billion. As of 2021, thermal management had been an ongoing issue for the F135, largely due to the increased sustainment and maintenance costs caused from heat damage by running the engines hotter in order to take full advantage of newer, more powerful sensors and electronics being integrated into Block 4+ F-35s. The sensors and electronics subsequently require additional cooling to take full advantage of

4450-645: The F135, and instead offered an adaptive three-stream fan as Growth Option 2.0 that is separate from the XA101, which would instead have a new engine core. In 2020, the F135 development plan shifted from "Growth Options" to "Engine Enhancement Packages" (EEP), while the three-stream XA101 is a new engine with potential re-engining for the F-35A. Ground testing of the XA101 began in September 2021. Also in September 2021, Pratt & Whitney publicly stated serious doubts about

4539-525: The US and UK rail networks. Pollution produced from centralised generation of electricity is emitted at a distant power station, rather than "on site". Pollution can be reduced by using more railway electrification and low carbon power for electricity. Some railways, such as the French SNCF and Swiss federal railways derive most, if not 100% of their power, from hydroelectric or nuclear power stations, therefore atmospheric pollution from their rail networks

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4628-522: The USAF chose an improved F135 under the Engine Core Upgrade (ECU) program over an adaptive cycle engine such as the XA101 due to cost as well as concerns over risk of integrating the new engine, initially designed for the F-35A, on the B and C. The XA101 is a three-stream adaptive cycle engine that can adjust the bypass ratio and fan pressure to increase fuel efficiency or thrust, depending on

4717-641: The Ukrainian KVS G-6, with a 3.5 km range and able to operate continuously for 30 minutes. The manufacturer states that the weapon can disrupt remote control, the transmission of video at 2.4 and 5 GHz, and GPS and Glonass satellite navigation signals. Ukraine has also used the EDM4S anti drone rifle to shoot down Russian Eleron-3 drones. Due to the threat posed by drones in regard to terrorism, several police forces have carried anti-drone guns as part of their equipment. For example, during

4806-684: The United States, the Pentagon , DARPA , the Air Force Research Laboratory , United States Army Armament Research Development and Engineering Center , and the Naval Research Laboratory are researching directed-energy weapons to counter ballistic missiles , hypersonic cruise missiles , and hypersonic glide vehicles . These systems of missile defense are expected to come online no sooner than

4895-422: The XA101 to be "Growth Option 2.0" in its long-term development plan for the F135. Further contract awards and modifications from Air Force Life Cycle Management Center (AFLCMC) in 2018 increased the focus on re-engining of the F-35; there has also been investigations on applying the technology in upgrades for F-15, F-16, and F-22 propulsion systems. In June 2018, Pratt & Whitney changed its development plan for

4984-528: The advantage of being self-focusing in the atmosphere. Blooming is also a problem in particle-beam weapons. Energy that would otherwise be focused on the target spreads out and the beam becomes less effective: Plasma weapons fire a beam, bolt, or stream of plasma , which is an excited state of matter consisting of atomic electrons and nuclei, and free electrons if ionized , or other particles if pinched . The MARAUDER ( Magnetically Accelerated Ring to Achieve Ultra-high Directed-Energy and Radiation ) used

5073-494: The aircraft's capability. GE had previously stated that one advantage of their AETP XA100 engine is its third airstream, which its officials say can be used to help cool the F-35’s electronics. Nonetheless, Latka urged an official review of the program's requirements, stating, “We need to crystallize on what the requirement is, and then we figure out what the most cost-effective solution is once we understand that requirement." In 2023

5162-422: The build-up of deposits (typically, on fuel injector and intake valve ) known to reduce fuel economy and engine performance. How fuel combusts affects how much energy is produced. The National Aeronautics and Space Administration (NASA) has investigated fuel consumption in microgravity . The common distribution of a flame under normal gravity conditions depends on convection , because soot tends to rise to

5251-633: The central nervous system and cause neurophysiological disorders may violate the Certain Conventional Weapons Convention of 1980. Weapons that go beyond non-lethal intentions and cause 'superfluous injury or unnecessary suffering' may also violate the Protocol I to the Geneva Conventions of 1977." Some common bio-effects of non-lethal electromagnetic weapons include: Interference with breathing poses

5340-541: The collapse of the SED (Socialist Unity Party of Germany) system. In the 1980s, U.S. President Ronald Reagan proposed the Strategic Defense Initiative (SDI) program, which was nicknamed Star Wars . It suggested that lasers, perhaps space-based X-ray lasers , could destroy ICBMs in flight. Panel discussions on the role of high-power lasers in SDI took place at various laser conferences, during

5429-495: The conversions between the chemical energy in the fuel and the kinetic energy of the vehicle. Driver behavior can affect fuel economy; maneuvers such as sudden acceleration and heavy braking waste energy. Energy-efficient driving techniques are used by drivers who wish to reduce their fuel consumption, and thus maximize fuel efficiency. Many drivers have the potential to improve their fuel efficiency significantly. The relationship between fuel consumption and driving behavior

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5518-400: The cost effectiveness of AETP's future for the F-35, stating that the XA101 was "always intended … to be a sixth-generation [powerplant for sixth-generation fighters]." Jennifer Latka, Vice President of the F135 program, explained: “There’s a significant amount of risk that comes with brand-new technology, and that would require a tremendous amount of validation to be done. We’re saying, the AETP

5607-429: The cruise liner Spirit of Adventure also defended itself from Somali pirates by using its LRAD to force them to retreat. The TECOM Technology Symposium in 1997 concluded on non-lethal weapons , "determining the target effects on personnel is the greatest challenge to the testing community", primarily because "the potential of injury and death severely limits human tests". Also, "directed-energy weapons that target

5696-712: The development of ruby and carbon dioxide lasers as anti-ballistic missile systems, and later as a tracking and anti-satellite system. There are reports that the Terra-3 complex at Sary Shagan was used on several occasions to temporarily "blind" US spy satellites in the IR range. It has been claimed that the USSR made use of the lasers at the Terra-3 site to target the Space Shuttle Challenger in 1984. At

5785-403: The difference between the two frequencies (infrasonic) e.g. two directional speakers emitting 16,000 Hz and 16,002 Hz frequencies would produce in the ear two frequencies of 32,002 Hz and 2 Hz. The article states: "The squawk box is highly directional which gives it its appeal. Its effective beam width is so small that it can be directed at individuals in a riot. Other members of

5874-460: The dish reflectors, caused vertigo and nausea at 200–400 meters (220–440 yd) by vibrating the middle ear bones and shaking the cochlear fluid within the inner ear . At distances of 50–200 meters (160–660 ft), the sound waves could act on organ tissues and fluids by repeatedly compressing and releasing compressive resistant organs such as the kidneys , spleen , and liver . (It had little detectable effect on malleable organs such as

5963-485: The health incidents. The cause of Havana syndrome remains unknown and controversial. LRADs are often fitted on commercial and military ships. They have been used on several occasions to repel pirate attacks by sending warnings and by producing intolerable levels of sound. For example, in 2005 the cruise liner Seabourn Spirit used a sonic weapon to defend itself from Somali pirates in the Indian ocean. A few years later,

6052-652: The incident. However, this story is comprehensively denied by the crew members of STS-41-G and knowledgeable members of the US intelligence community. After the end of the Cold War , the Terra-3 facility was found to be a low-power laser testing site with limited satellite tracking capabilities, which is now abandoned and partially disassembled. Havana syndrome is a disputed medical condition reported by US personnel in Havana, Cuba and other locations, originally suspected to be caused by microwave radiation . In January 2022,

6141-521: The mid to late-2020s. China, France, Germany, the United Kingdom, Russia, India, Israel, and Pakistan are also developing military-grade directed-energy weapons, while Iran and Turkey claim to have them in active service. The first use of directed-energy weapons in combat between military forces was claimed to have occurred in Libya in August 2019 by Turkey, which claimed to use

6230-630: The modern German state was investigating the possibility that this X-ray equipment was being used as weaponry and that it was a deliberate policy of the Stasi to attempt to give prisoners radiation poisoning, and thereby cancer, through the use of directed X-rays. The negative effects of the radiation poisoning and cancer would extend past the period of incarceration. In this manner someone could be debilitated even though they were no longer imprisoned. The historian Mary Fulbrook states, The subsequent serious illnesses and premature deaths of dissidents such as

6319-488: The net heat of combustion gives the theoretical amount of mechanical energy (work) that can be obtained from the reaction. (This is given by the change in Gibbs free energy , and is around 45.7 MJ/kg for gasoline.) The actual amount of mechanical work obtained from fuel (the inverse of the specific fuel consumption ) depends on the engine. A figure of 17.6 MJ/kg is possible with a gasoline engine, and 19.1 MJ/kg for

6408-505: The novelist Jürgen Fuchs, and the author of the critical analysis of 'The Alternative in Eastern Europe', Rudolf Bahro, have been linked by some to the suspicion of exposure to extraordinarily high and sustained levels of X-rays while waiting for interrogations, and being strapped to unpleasant chairs in small prison cells in front of mysterious closed boxes- boxes that, along with their mysterious apparatus, curiously disappeared after

6497-557: The out-of-control drone then crashes. The Russian Stupor is reported to have a range of two kilometers, covering a 20-degree sector; it also suppresses the drone's cameras. Stupor is reported to have been used by Russian forces during the Russian military intervention in the Syrian civil war . Both Russia and Ukraine are reported to use these devices during the 2022 Russian invasion of Ukraine . The Ukrainian army are reported to use

6586-618: The policing of the Commonwealth Games in 2018, the Australian Queensland Police Service carried anti-drone guns with an effective range of 3 km (2 mi). In Myanmar, police have been equipped with anti-drone guns "ostensibly to defend VIPs". This UK-developed system was unveiled in May 2024 and uses radio waves to fry the electronic components of its targets, rendering them inoperable. It

6675-410: The potential employment of directed-energy weapons in the future. When additional thrust is needed, the air from the third stream can be directed into the core and fan streams for increased performance. Data from Flight Global, Related development Comparable engines Related lists Fuel efficiency Fuel efficiency (or fuel economy ) is a form of thermal efficiency , meaning

6764-426: The same batch of fuel. One is the high (or gross) heat of combustion and the other is the low (or net) heat of combustion. The high value is obtained when, after the combustion, the water in the exhaust is in liquid form. For the low value, the exhaust has all the water in vapor form (steam). Since water vapor gives up heat energy when it changes from vapor to liquid, the liquid water value is larger since it includes

6853-410: The scenario. It does this by employing a third bypass stream around the entire engine, with the ability to modulate the portion of airflow into the engine core or through this third stream, to increase fuel economy and act as a heat sink for cooling. This capability enables greater use of the high-speed, low-altitude portion of the F-35 flight regime. The increased cooling and power generation also enables

6942-405: The surface-to-air missile's guidance system, deflecting it from the aircraft. Vigilant Eagle was not mentioned on Raytheon's Web site in 2022. Bofors HPM Blackout is a high-powered microwave weapon that is said to be able to destroy at short distance a wide variety of commercial off-the-shelf (COTS) electronic equipment and is purportedly non-lethal. The effective radiated power (ERP) of

7031-424: The system could cause irreversible damage to the eyes. There has yet to be testing for long-term side effects of exposure to the microwave beam. It can also destroy unshielded electronics . Vigilant Eagle is a ground-based airport defense system that directs high-frequency microwaves towards any projectile that is fired at an aircraft. It was announced by Raytheon in 2005, and the effectiveness of its waveforms

7120-408: The tailpipe (exhaust pipe). Potentially the atmospheric pollution could be minimal, provided the hydrogen is made by electrolysis using electricity from non-polluting sources such as solar, wind or hydroelectricity or nuclear. Commercial hydrogen production uses fossil fuels and produces more carbon dioxide than hydrogen. Because there are pollutants involved in the manufacture and destruction of

7209-514: The test were to assess NPB propagation characteristics in space and gauge the effects on spacecraft components. Despite continued research into NPBs, no known weapon system utilizing this technology has been deployed. Though the strategic missile defense concept has continued to the present under the Missile Defense Agency , most of the directed-energy weapon concepts were shelved. However, Boeing has been somewhat successful with

7298-473: The time, the Soviet Union was concerned that the shuttle was being used as a reconnaissance platform. On 10 October 1984 ( STS-41-G ), the Terra-3 tracking laser was allegedly aimed at Challenger as it passed over the facility. Early reports claimed that this was responsible for causing "malfunctions on the space shuttle and distress to the crew", and that the United States filed a diplomatic protest about

7387-435: The top of a flame, such as in a candle, making the flame yellow. In microgravity or zero gravity , such as an environment in outer space , convection no longer occurs, and the flame becomes spherical , with a tendency to become more blue and more efficient. There are several possible explanations for this difference, of which the most likely one given is the hypothesis that the temperature is evenly distributed enough that soot

7476-477: The vicinity for the twenty minutes or so needed for a test. Reversing the order of events in retelling the story created a "tale" where tourists car engine stopped first and then were approached by a German soldier who told them that they had to wait. The soldier returned a short time later to say that the engine would now work and the tourists drove off. Such stories were circulating in Britain around 1938 and during

7565-587: The war British Intelligence relaunched the myth as a "British engine-stopping ray," trying to spoof the Germans into researching what the British had supposedly invented in an attempt to tie up German scientific resources. During the early 1940s Axis engineers developed a sonic cannon that could cause fatal vibrations in its target body. A methane gas combustion chamber leading to two parabolic dishes pulse-detonated at roughly 44 Hz . This sound, magnified by

7654-617: Was among several directed energy weapons examined by the Strategic Defense Initiative Organization for potential use in missile defense. In July 1989, the accelerator was launched from White Sands Missile Range as part of the Beam Experiment Aboard Rocket (BEAR) project, reaching an altitude of 200 kilometers (124 miles) and operating successfully in space before being recovered intact after reentry. The primary objectives of

7743-511: Was called decomposition (transl. Zersetzung ). In the 1970s and 1980s it became the primary method of repressing domestic "hostile-negative" forces. Some of the victims of this method suffered from cancer and claimed that they had also been targeted with directed X-rays . In addition, when the East German state collapsed, powerful X-ray equipment was found in prisons without there being any apparent reason to justify its presence. In 1999,

7832-595: Was possible. He and colleague Arnold Wilkins quickly concluded that it was not feasible, but as a consequence suggested using radio for the detection of aircraft and this started the development of radar in Britain. Stories in the 1930s and World War II gave rise to the idea of an "engine-stopping ray". They seemed to have arisen from the testing of the television transmitter in Feldberg , Germany. Because electrical noise from car engines would interfere with field strength measurements, sentries would stop all traffic in

7921-416: Was reported to have been demonstrated in field tests to be highly effective in defeating MANPADS missiles. The system consists of a missile-detecting and tracking subsystem (MDT), a command and control system, and a scanning array. The MDT is a fixed grid of passive infrared (IR) cameras. The command and control system determines the missile launch point. The scanning array projects microwaves that disrupt

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