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RS-68 being tested at NASA's Stennis Space Center Viking 5C rocket engine used on Ariane 1 through Ariane 4. A rocket engine is a reaction engine, producing thrust in accordance with Newton's third law by ejecting reaction mass rearward, usually a high-speed jet of high-temperature gas produced by the combustion of rocket propellants stored inside the rocket.
A space vehicle's flight is determined by application of Newton's second law of motion: =, where F is the vector sum of all forces exerted on the vehicle, m is its current mass, and a is the acceleration vector, the instantaneous rate of change of velocity (v), which in turn is the instantaneous rate of change of displacement.
For rocket-like propulsion systems, this is a function of mass fraction and exhaust velocity; mass fraction for rocket-like systems is usually limited by propulsion system weight and tankage weight. [ citation needed ] For a system to achieve this limit, the payload may need to be a negligible percentage of the vehicle, and so the practical ...
Ammonium perchlorate composite propellant (APCP) is a solid rocket propellant.It differs from many traditional solid rocket propellants such as black powder or zinc-sulfur, not only in chemical composition and overall performance but also by being cast into shape, as opposed to powder pressing as with black powder.
The rocket is launched using liquid hydrogen and liquid oxygen cryogenic propellants. Rocket propellant is used as reaction mass ejected from a rocket engine to produce thrust . The energy required can either come from the propellants themselves, as with a chemical rocket , or from an external source, as with ion engines .
The Tsiolkovsky rocket equation, or ideal rocket equation, can be useful for analysis of maneuvers by vehicles using rocket propulsion. [2] A rocket applies acceleration to itself (a thrust) by expelling part of its mass at high speed. The rocket itself moves due to the conservation of momentum.
In rockets for a given target orbit, a rocket's mass fraction is the portion of the rocket's pre-launch mass (fully fueled) that does not reach orbit.The propellant mass fraction is the ratio of just the propellant to the entire mass of the vehicle at takeoff (propellant plus dry mass).
Rocket propulsion Excess speed of an interplanetary transfer orbit is typically shed with a rocket firing known as an orbit insertion burn. For such a maneuver, the spacecraft's engine is used to slow its velocity relative to the target body. [ 2 ]