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Retrorocket
A retrorocket (short for ''retrograde rocket'') is a rocket engine providing thrust opposing the motion of a vehicle, thereby causing it to decelerate. They have mostly been used in spacecraft, with more limited use in short-runway aircraft landing. New uses are emerging since 2010 for retro-thrust rockets in reusable launch systems. History Rockets were fitted to the nose of some models of the DFS 230, a World War II German Military glider. This enabled the aircraft to land in more confined areas than would otherwise be possible during an airborne assault. Another World War II development was the British Hajile project, initiated by the British Admiralty's Directorate of Miscellaneous Weapons Development. Originally a request from the British Army as a method to drop heavy equipment or vehicles from aircraft flying at high speeds and altitudes, the project turned out to be a disaster and was largely forgotten after the war. Although some of the tests turned out to be succe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Project Gemini
Project Gemini () was the second United States human spaceflight program to fly. Conducted after the first American crewed space program, Project Mercury, while the Apollo program was still in early development, Gemini was conceived in 1961 and concluded in 1966. The Gemini spacecraft carried a two-astronaut crew. Ten Gemini crews and 16 individual astronauts flew low Earth orbit (LEO) missions during 1965 and 1966. Gemini's objective was the development of space travel techniques to support the Apollo mission to Moon landing, land astronauts on the Moon. In doing so, it allowed the United States to catch up and overcome the lead in human spaceflight capability the Soviet Union had obtained in the early years of the Space Race, by demonstrating mission endurance up to just under 14 days, longer than the eight days required for a round trip to the Moon; methods of performing extravehicular activity (EVA) without tiring; and the orbital maneuvers necessary to achieve space rendezv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Project Mercury
Project Mercury was the first human spaceflight program of the United States, running from 1958 through 1963. An early highlight of the Space Race, its goal was to put a man into Earth orbit and return him safely, ideally before the Soviet Union. Taken over from the US Air Force by the newly created civilian space agency NASA, it conducted 20 uncrewed developmental flights (some using animals), and six successful flights by astronauts. The program, which took its name from Roman mythology, cost $ (adjusted for inflation). The astronauts were collectively known as the " Mercury Seven", and each spacecraft was given a name ending with a "7" by its pilot. The Space Race began with the 1957 launch of the Soviet satellite Sputnik 1. This came as a shock to the American public, and led to the creation of NASA to expedite existing US space exploration efforts, and place most of them under civilian control. After the successful launch of the Explorer 1 satellite in 1958, crewed spac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
S-IC
The S-IC (pronounced S-one-C) was the first stage of the American Saturn V rocket. The S-IC stage was manufactured by the Boeing Company. Like the first stages of most rockets, more than 90% of the mass at launch was propellant, in this case RP-1 rocket fuel and liquid oxygen (LOX) oxidizer. It was tall and in diameter. The stage provided of thrust at sea level to get the rocket through the first of ascent. The stage had five F-1 engines in a quincunx arrangement. The center engine was fixed in position, while the four outer engines could be hydraulically gimballed to control the rocket. Manufacturing The Boeing Co. was awarded the contract to manufacture the S-IC on December 15, 1961. By this time the general design of the stage had been decided on by the engineers at the Marshall Space Flight Center (MSFC). The main place of manufacture was the Michoud Assembly Facility, New Orleans. Wind tunnel testing took place in Seattle and the machining of the tools needed to build ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rocket Assisted Descent
A rocket (from , and so named for its shape) is a vehicle that uses jet propulsion to accelerate without using any surrounding air. A rocket engine produces thrust by Reaction (physics), reaction to exhaust expelled at high speed. Rocket engines work entirely from rocket propellant, propellant carried within the vehicle; therefore a rocket can fly in the vacuum of space. Rockets work more efficiently in a vacuum and incur a loss of thrust due to the opposing pressure of the atmosphere. Multistage rockets are capable of attaining escape velocity from Earth and therefore can achieve unlimited maximum altitude. Compared with Airbreathing jet engine, airbreathing engines, rockets are lightweight and powerful and capable of generating large accelerations. To control their flight, rockets rely on momentum, airfoils, Reaction control system, auxiliary reaction engines, gimballed thrust, Reaction wheel, momentum wheels, Thrust vectoring, deflection of the exhaust stream, propellant fl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hajile
Hajile (Elijah Backwards) was an experimental project developed by the British Admiralty's Directorate of Miscellaneous Weapons Development (DMWD) during the final years of Second World War for slowing the landing of air-dropped supplies with retrorockets. Development The project was initiated by a request from the Army for a method of dropping heavy equipment and vehicles from aircraft at high speed, retaining the materiel's terminal velocity for as long as possible in order to minimise drift and damage from anti-aircraft gun batteries. It was further required that the materiel suffer only minimal or no damage from landing, and once dropped be ready to deploy within minutes. The high falling speed ruled out parachutes, so the DMWD came up with the idea of loading the drops onto a platform surrounded with cordite rockets. These would fire at the last instant to decelerate the materiel to a safe landing speed. The initial test produced the project's codename; as the rockets' exhaus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Service Propulsion System
The Apollo command and service module (CSM) was one of two principal components of the United States Apollo spacecraft, used for the Apollo program, which landed astronauts on the Moon between 1969 and 1972. The CSM functioned as a mother ship, which carried a crew of three astronauts and the second Apollo spacecraft, the Apollo Lunar Module, to lunar orbit, and brought the astronauts back to Earth. It consisted of two parts: the conical command module, a cabin that housed the crew and carried equipment needed for atmospheric reentry and splashdown; and the cylindrical service module which provided propulsion, electrical power and storage for various consumables required during a mission. An umbilical connection transferred power and consumables between the two modules. Just before reentry of the command module on the return home, the umbilical connection was severed and the service module was cast off and allowed to burn up in the atmosphere. The CSM was developed and built f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atmospheric Entry
Atmospheric entry (sometimes listed as Vimpact or Ventry) is the movement of an object from outer space into and through the gases of an atmosphere of a planet, dwarf planet, or natural satellite. Atmospheric entry may be ''uncontrolled entry,'' as in the entry of astronomical objects, space debris, or bolides. It may be ''controlled entry'' (or ''reentry'') of a spacecraft that can be navigated or follow a predetermined course. Methods for controlled atmospheric ''entry, descent, and landing'' of spacecraft are collectively termed as ''EDL''. Objects entering an atmosphere experience atmospheric drag, which puts mechanical stress on the object, and aerodynamic heating—caused mostly by compression of the air in front of the object, but also by drag. These forces can cause loss of mass ( ablation) or even complete disintegration of smaller objects, and objects with lower compressive strength can explode. Objects have reentered with speeds ranging from 7.8 km/s for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atmospheric Reentry
Atmospheric entry (sometimes listed as Vimpact or Ventry) is the movement of an object from outer space into and through the gases of an atmosphere of a planet, dwarf planet, or natural satellite. Atmospheric entry may be ''uncontrolled entry,'' as in the entry of astronomical objects, space debris, or bolides. It may be ''controlled entry'' (or ''reentry'') of a spacecraft that can be navigated or follow a predetermined course. Methods for controlled atmospheric ''entry, descent, and landing'' of spacecraft are collectively termed as ''EDL''. Objects entering an atmosphere experience Drag (physics), atmospheric drag, which puts mechanical stress on the object, and aerodynamic heating—caused mostly by compression of the air in front of the object, but also by drag. These forces can cause loss of mass (ablation) or even complete disintegration of smaller objects, and objects with lower compressive strength can explode. Objects have reentered with speeds ranging from 7.8&n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apollo Command And Service Module
The Apollo command and service module (CSM) was one of two principal components of the United States Apollo (spacecraft), Apollo spacecraft, used for the Apollo program, which landed astronauts on the Moon between 1969 and 1972. The CSM functioned as a mother ship, which carried a crew of three astronauts and the second Apollo spacecraft, the Apollo Lunar Module, to lunar orbit, and brought the astronauts back to Earth. It consisted of two parts: the conical command module, a cabin that housed the crew and carried equipment needed for atmospheric reentry and splashdown (spacecraft landing), splashdown; and the cylindrical service module which provided propulsion, electrical power and storage for various consumables required during a mission. An umbilical cable, umbilical connection transferred power and consumables between the two modules. Just before reentry of the command module on the return home, the umbilical connection was severed and the service module was cast off and al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reusable Launch System
A reusable launch vehicle has parts that can be recovered and reflown, while carrying payloads from the surface to outer space. Rocket stages are the most common launch vehicle parts aimed for reuse. Smaller parts such as fairings, boosters or rocket engines can also be reused, though reusable spacecraft may be launched on top of an expendable launch vehicle. Reusable launch vehicles do not need to make these parts for each launch, therefore reducing its launch cost significantly. However, these benefits are diminished by the cost of recovery and refurbishment. Reusable launch vehicles may contain additional avionics and propellant, making them heavier than their expendable counterparts. Reused parts may need to enter the atmosphere and navigate through it, so they are often equipped with heat shields, grid fins, and other flight control surfaces. By modifying their shape, spaceplanes can leverage aviation mechanics to aid in its recovery, such as gliding or lift. In the a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Military Glider
Military gliders (an offshoot of common gliders) have been used by the militaries of various countries for carrying troops ( glider infantry) and heavy equipment to a combat zone, mainly during the Second World War. These engineless aircraft were towed into the air and most of the way to their target by military transport planes, e.g., C-47 Skytrain or Dakota, or bombers relegated to secondary activities, e.g., Short Stirling. Most military gliders do not soar, although there were attempts to build military sailplanes as well, such as the DFS 228. Once released from the tow craft near the front, they were to land on any convenient open terrain close to the target, hopefully with as little damage to the cargo and crew as possible, as most landing zones (LZ) were far from ideal. The one-way nature of the missions meant that they were treated as semi-expendable leading to construction from common and inexpensive materials such as wood. Most nations seriously attempted to recover ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
