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Grasshopper (robot Weather Station)
The Grasshopper was a project by the United States Air Force and United States Navy to develop a portable robot weather station deployed by parachute from long range aircraft in the early 1950s. The Grasshopper was designed to be deployed by parachute into enemy territory and radio back basic weather information for air strikes. With the USAF ''Grasshopper'' after being parachuted down from a long range aircraft, a small explosive charge disconnects the parachute upon impact with the ground. After a selected preset time, a second explosive charge would deploy the legs of the unit while setting it upright on the ground. Finally, a third explosive charge would extend the antenna Antenna ( antennas or antennae) may refer to: Science and engineering * Antenna (radio), also known as an aerial, a transducer designed to transmit or receive electromagnetic (e.g., TV or radio) waves * Antennae Galaxies, the name of two collid ... and make the unit ready to begin taking weather ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States Air Force
The United States Air Force (USAF) is the air service branch of the United States Armed Forces, and is one of the eight uniformed services of the United States. Originally created on 1 August 1907, as a part of the United States Army Signal Corps, the USAF was established as a separate branch of the United States Armed Forces in 1947 with the enactment of the National Security Act of 1947. It is the second youngest branch of the United States Armed Forces and the fourth in order of precedence. The United States Air Force articulates its core missions as air supremacy, global integrated intelligence, surveillance and reconnaissance, rapid global mobility, global strike, and command and control. The United States Air Force is a military service branch organized within the Department of the Air Force, one of the three military departments of the Department of Defense. The Air Force through the Department of the Air Force is headed by the civilian Secretary of the Air Force ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States Navy
The United States Navy (USN) is the maritime service branch of the United States Armed Forces and one of the eight uniformed services of the United States. It is the largest and most powerful navy in the world, with the estimated tonnage of its active battle fleet alone exceeding the next 13 navies combined, including 11 allies or partner nations of the United States as of 2015. It has the highest combined battle fleet tonnage (4,635,628 tonnes as of 2019) and the world's largest aircraft carrier fleet, with eleven in service, two new carriers under construction, and five other carriers planned. With 336,978 personnel on active duty and 101,583 in the Ready Reserve, the United States Navy is the third largest of the United States military service branches in terms of personnel. It has 290 deployable combat vessels and more than 2,623 operational aircraft . The United States Navy traces its origins to the Continental Navy, which was established during the American Revo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Weather Station
A weather station is a facility, either on land or sea, with instruments and equipment for measuring atmospheric conditions to provide information for weather forecasts and to study the weather and climate. The measurements taken include temperature, atmospheric pressure, humidity, wind speed, wind direction, and precipitation amounts. Wind measurements are taken with as few other obstructions as possible, while temperature and humidity measurements are kept free from direct solar radiation, or insolation. Manual observations are taken at least once daily, while automated measurements are taken at least once an hour. Weather conditions out at sea are taken by ships and buoys, which measure slightly different meteorological quantities such as sea surface temperature (SST), wave height, and wave period. Drifting weather buoys outnumber their moored versions by a significant amount. Weather instruments Typical weather stations have the following instruments: * Thermometer for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parachute
A parachute is a device used to slow the motion of an object through an atmosphere by creating drag or, in a ram-air parachute, aerodynamic lift. A major application is to support people, for recreation or as a safety device for aviators, who can exit from an aircraft at height and descend safely to earth. A parachute is usually made of a light, strong fabric. Early parachutes were made of silk. The most common fabric today is nylon. A parachute's canopy is typically dome-shaped, but some are rectangles, inverted domes, and other shapes. A variety of loads are attached to parachutes, including people, food, equipment, space capsules, and bombs. History Middle Ages In 852, in Córdoba, Spain, the Moorish man Armen Firman attempted unsuccessfully to fly by jumping from a tower while wearing a large cloak. It was recorded that "there was enough air in the folds of his cloak to prevent great injury when he reached the ground." Early Renaissance The earliest evidence f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radio Transmission
Radio is the technology of signaling and communicating using radio waves. Radio waves are electromagnetic waves of frequency between 30 hertz (Hz) and 300 gigahertz (GHz). They are generated by an electronic device called a transmitter connected to an antenna which radiates the waves, and received by another antenna connected to a radio receiver. Radio is very widely used in modern technology, in radio communication, radar, radio navigation, remote control, remote sensing, and other applications. In radio communication, used in radio and television broadcasting, cell phones, two-way radios, wireless networking, and satellite communication, among numerous other uses, radio waves are used to carry information across space from a transmitter to a receiver, by modulating the radio signal (impressing an information signal on the radio wave by varying some aspect of the wave) in the transmitter. In radar, used to locate and track objects like aircraft, ships, spacecraft an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Weather Forecasting
Weather forecasting is the application of science and technology forecasting, to predict the conditions of the Earth's atmosphere, atmosphere for a given location and time. People have attempted to predict the weather informally for millennia and formally since the 19th century. Weather forecasts are made by collecting quantitative data about the current state of the atmosphere, land, and ocean and using meteorology to project how the atmosphere will change at a given place. Once calculated manually based mainly upon changes in atmospheric pressure, barometric pressure, current weather conditions, and sky condition or cloud cover, weather forecasting now relies on numerical weather prediction, computer-based models that take many atmospheric factors into account. Human input is still required to pick the best possible forecast model to base the forecast upon, which involves pattern recognition skills, teleconnections, knowledge of model performance, and knowledge of model biases ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Air Strikes
An airstrike, air strike or air raid is an offensive operation carried out by aircraft. Air strikes are delivered from aircraft such as blimps, balloons, fighters, heavy bombers, ground attack aircraft, attack helicopters and drones. The official definition includes all sorts of targets, including enemy air targets, but in popular usage the term is usually narrowed to a tactical (small-scale) attack on a ground or naval objective as opposed to a larger, more general attack such as carpet bombing. Weapons used in an airstrike can range from direct-fire aircraft-mounted cannons and machine guns, rockets and air-to-surface missiles, to various types of aerial bombs, glide bombs, cruise missiles, ballistic missiles, and even directed-energy weapons such as laser weapons. In close air support, air strikes are usually controlled by trained observers on the ground for coordination with ground troops and intelligence in a manner derived from artillery tactics. History Begi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aircraft
An aircraft is a vehicle that is able to fly by gaining support from the air. It counters the force of gravity by using either static lift or by using the dynamic lift of an airfoil, or in a few cases the downward thrust from jet engines. Common examples of aircraft include airplanes, helicopters, airships (including blimps), gliders, paramotors, and hot air balloons. The human activity that surrounds aircraft is called ''aviation''. The science of aviation, including designing and building aircraft, is called '' aeronautics.'' Crewed aircraft are flown by an onboard pilot, but unmanned aerial vehicles may be remotely controlled or self-controlled by onboard computers. Aircraft may be classified by different criteria, such as lift type, aircraft propulsion, usage and others. History Flying model craft and stories of manned flight go back many centuries; however, the first manned ascent — and safe descent — in modern times took place by larger hot-air ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Explosive Charge
An explosive (or explosive material) is a reactive substance that contains a great amount of potential energy that can produce an explosion if released suddenly, usually accompanied by the production of light, heat, sound, and pressure. An explosive charge is a measured quantity of explosive material, which may either be composed solely of one ingredient or be a mixture containing at least two substances. The potential energy stored in an explosive material may, for example, be * chemical energy, such as nitroglycerin or grain dust * pressurized gas, such as a gas cylinder, aerosol can, or BLEVE * nuclear energy, such as in the fissile isotopes uranium-235 and plutonium-239 Explosive materials may be categorized by the speed at which they expand. Materials that detonate (the front of the chemical reaction moves faster through the material than the speed of sound) are said to be "high explosives" and materials that deflagrate are said to be "low explosives". Explosives may also ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antenna (radio)
In radio engineering, an antenna or aerial is the interface between radio waves propagating through space and electric currents moving in metal conductors, used with a transmitter or receiver. In transmission, a radio transmitter supplies an electric current to the antenna's terminals, and the antenna radiates the energy from the current as electromagnetic wave In physics, electromagnetic radiation (EMR) consists of waves of the electromagnetic (EM) field, which propagate through space and carry momentum and electromagnetic radiant energy. It includes radio waves, microwaves, infrared, (visib ...s (radio waves). In Receiver (radio), reception, an antenna intercepts some of the power of a radio wave in order to produce an electric current at its terminals, that is applied to a receiver to be Amplifier, amplified. Antennas are essential components of all radio equipment. An antenna is an array of conductor (material), conductors (Driven element, elements), elect ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Strike Aircraft
An attack aircraft, strike aircraft, or attack bomber is a tactical military aircraft that has a primary role of carrying out airstrikes with greater precision than bombers, and is prepared to encounter strong low-level air defenses while pressing the attack.Mortensen 1987, pp. 24–25. This class of aircraft is designed mostly for close air support and naval air-to-surface missions, overlapping the tactical bomber mission. Designs dedicated to non-naval roles are often known as ground-attack aircraft.Gunston 2009, p. 73. Fighter aircraft often carry out the attack role, although they would not be considered attack aircraft ''per se'', although fighter-bomber conversions of those same aircraft would be considered part of the class. Strike fighters, which have effectively replaced the fighter-bomber and light bomber concepts, also differ little from the broad concept of an attack aircraft. The dedicated attack aircraft as a separate class existed primarily during and aft ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
