Topic: Military history/Military science, technology, and theory (Page 7)
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🔗 FOGBANK
FOGBANK is a code name given to a material used in nuclear weapons such as the W76, W78 and W80.
FOGBANK's precise nature is classified; in the words of former Oak Ridge general manager Dennis Ruddy, "The material is classified. Its composition is classified. Its use in the weapon is classified, and the process itself is classified." Department of Energy Nuclear Explosive Safety documents simply describe it as a material "used in nuclear weapons and nuclear explosives" along with lithium hydride (LiH) and lithium deuteride (LiD), beryllium (Be), uranium hydride (UH3), and plutonium hydride.
However National Nuclear Security Administration (NNSA) Administrator Tom D'Agostino disclosed the role of FOGBANK in the weapon: "There's another material in the—it's called interstage material, also known as fog bank", and arms experts believe that FOGBANK is an aerogel material which acts as an interstage material in a nuclear warhead; i.e., a material designed to become a superheated plasma following the detonation of the weapon's fission stage, the plasma then triggering the fusion-stage detonation.
Discussed on
- "FOGBANK – How USA forgot how to manufacture an essential ingredient for nukes" | 2017-09-25 | 22 Upvotes 6 Comments
🔗 Polybolos
Polybolos, meaning "multi thrower" in Greek, was an ancient Greek repeating ballista reputedly invented by Dionysius of Alexandria, a 3rd-century BC Greek engineer at the Rhodes arsenal, and used in antiquity.
Philo of Byzantium encountered and described a weapon similar to the polybolos, a catapult that like a modern machine gun could fire again and again without a need to reload. Philo left a detailed description of the gears that powered its chain drive, the oldest known application of such a mechanism, and that placed bolt after bolt into its firing slot.
Discussed on
- "Polybolos" | 2015-11-13 | 30 Upvotes 7 Comments
🔗 Communication with Submarines
Communication with submarines is a field within military communications that presents technical challenges and requires specialized technology. Because radio waves do not travel well through good electrical conductors like salt water, submerged submarines are cut off from radio communication with their command authorities at ordinary radio frequencies. Submarines can surface and raise an antenna above the sea level, then use ordinary radio transmissions, however this makes them vulnerable to detection by anti-submarine warfare forces. Early submarines during World War II mostly traveled on the surface because of their limited underwater speed and endurance; they dove mainly to evade immediate threats. During the Cold War, however, nuclear-powered submarines were developed that could stay submerged for months. Transmitting messages to these submarines is an active area of research. Very low frequency (VLF) radio waves can penetrate seawater a few hundred feet, and many navies use powerful VLF transmitters for submarine communications. A few nations have built transmitters which use extremely low frequency (ELF) radio waves, which can penetrate seawater to reach submarines at operating depths, but these require huge antennas. Other techniques that have been used include sonar and blue lasers.
Discussed on
- "Communication with Submarines" | 2016-12-26 | 10 Upvotes 1 Comments
- "Communication with submarines" | 2009-06-05 | 19 Upvotes 5 Comments
🔗 Five Eyes
The Five Eyes (FVEY) is an anglophone intelligence alliance comprising Australia, Canada, New Zealand, the United Kingdom and the United States. These countries are parties to the multilateral UKUSA Agreement, a treaty for joint cooperation in signals intelligence.
The origins of the FVEY can be traced back to the post–World War II period, when the Atlantic Charter was issued by the Allies to lay out their goals for a post-war world. During the course of the Cold War, the ECHELON surveillance system was initially developed by the FVEY to monitor the communications of the former Soviet Union and the Eastern Bloc, although it is now used to monitor billions of private communications worldwide.
In the late 1990s, the existence of ECHELON was disclosed to the public, triggering a major debate in the European Parliament and, to a lesser extent, the United States Congress. As part of efforts in the ongoing War on Terror since 2001, the FVEY further expanded their surveillance capabilities, with much emphasis placed on monitoring the World Wide Web. The former NSA contractor Edward Snowden described the Five Eyes as a "supra-national intelligence organisation that does not answer to the known laws of its own countries". Documents leaked by Snowden in 2013 revealed that the FVEY has been spying on one another's citizens and sharing the collected information with each other in order to circumvent restrictive domestic regulations on surveillance of citizens.
In spite of continued controversy over its methods, the Five Eyes relationship remains one of the most comprehensive known espionage alliances in history.
Since processed intelligence is gathered from multiple sources, the intelligence shared is not restricted to signals intelligence (SIGINT) and often involves defence intelligence as well as human intelligence (HUMINT) and geospatial intelligence (GEOINT). The following table provides an overview of most of the FVEY agencies involved in such forms of data sharing.
🔗 Project Habakkuk, Britain's plan to build an aircraft carrier from ice
Project Habakkuk or Habbakuk (spelling varies) was a plan by the British during the Second World War to construct an aircraft carrier out of pykrete (a mixture of wood pulp and ice) for use against German U-boats in the mid-Atlantic, which were beyond the flight range of land-based planes at that time. The idea came from Geoffrey Pyke, who worked for Combined Operations Headquarters. After promising scale tests and the creation of a prototype on a lake (Patricia Lake, Jasper National Park) in Alberta, Canada, the project was shelved due to rising costs, added requirements, and the availability of longer-range aircraft and escort carriers which closed the Mid-Atlantic gap the project was intended to address.
Discussed on
- "Project Habakkuk, Britain's plan to build an aircraft carrier from ice" | 2019-01-13 | 13 Upvotes 1 Comments
🔗 Hafnium Controversy
The hafnium controversy is a debate over the possibility of 'triggering' rapid energy releases, via gamma ray emission, from a nuclear isomer of hafnium, 178m2Hf. The energy release is potentially 5 orders of magnitude (100,000 times) more energetic than a chemical reaction, but 2 orders of magnitude less than a nuclear fission reaction. In 1998, a group led by Carl Collins of the University of Texas at Dallas reported having successfully initiated such a trigger. Signal-to-noise ratios were small in those first experiments, and to date no other group has been able to duplicate these results. Peter Zimmerman described claims of weaponization potential as having been based on "very bad science".
🔗 Corona reconnaissance satellites
The Corona program was a series of American strategic reconnaissance satellites produced and operated by the Central Intelligence Agency Directorate of Science & Technology with substantial assistance from the U.S. Air Force. The Corona satellites were used for photographic surveillance of the Soviet Union (USSR), the People's Republic of China, and other areas beginning in June 1959 and ending in May 1972.
Discussed on
- "Corona reconnaissance satellites" | 2015-11-13 | 26 Upvotes 4 Comments
🔗 Venetian Arsenal
The Venetian Arsenal (Italian: Arsenale di Venezia) is a complex of former shipyards and armories clustered together in the city of Venice in northern Italy. Owned by the state, the Arsenal was responsible for the bulk of the Venetian republic's naval power from the late Middle Ages to the early modern period. It was "one of the earliest large-scale industrial enterprises in history".
Discussed on
- "Venetian Arsenal" | 2023-05-28 | 27 Upvotes 2 Comments
🔗 Fifth-Generation Warfare
Fifth-generation warfare (5GW) is warfare that is conducted primarily through non-kinetic military action, such as social engineering, misinformation, cyberattacks, along with emerging technologies such as artificial intelligence and fully autonomous systems. Fifth generation warfare has been described by Daniel Abbot as a war of "information and perception". There is no widely agreed upon definition of fifth-generation warfare, and it has been rejected by some scholars, including William S. Lind, who was one of the original theorists of fourth-generation warfare.
Discussed on
- "Fifth-Generation Warfare" | 2023-11-08 | 26 Upvotes 3 Comments
🔗 Thermobaric Weapon
A thermobaric weapon, aerosol bomb, or vacuum bomb is a type of explosive that uses oxygen from the surrounding air to generate a high-temperature explosion. In practice, the blast wave typically produced by such a weapon is of a significantly longer duration than that of a conventional condensed explosive. The fuel–air explosive is one of the best-known types of thermobaric weapon.
Most conventional explosives consist of a fuel–oxidizer premix (black powder, for example, contains 25% fuel and 75% oxidizer), but thermobaric weapons are almost 100% fuel and so are significantly more energetic than conventional condensed explosives of equal weight. Their reliance on atmospheric oxygen makes them unsuitable for use under water, at high altitude, and in adverse weather. They are, however, considerably more destructive when used against field fortifications such as foxholes, tunnels, bunkers, and caves, partly because of the sustained blast wave and partly by the consumption of the oxygen inside it.
Many types of thermobaric weapons can be fitted to hand-held launchers.
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- "Thermobaric Weapon" | 2022-02-28 | 20 Upvotes 9 Comments