|
In spaceflight, a launch vehicle or carrier rocket is a rocket used to carry a payload from Earth's surface into outer space. A launch system includes the launch vehicle, the launch pad, and other infrastructure.〔 See for example: (【引用サイトリンク】title=NASA Kills 'Wounded' Launch System Upgrade at KSC )〕 Although a carrier rocket's payload is often an artificial satellite placed into orbit, some spaceflights, such as sounding rockets, are sub-orbital, while others enable spacecraft to escape Earth orbit entirely. Earth orbital launch vehicles typically have at least two stages, and sometimes as many as four or more. == Types == Expendable launch vehicles are designed for one-time use. They usually separate from their payload and disintegrate during atmospheric reentry. In contrast, reusable launch vehicles are designed to be recovered intact and launched again. The Space Shuttle was the only launch vehicle with components used for multiple orbital spaceflights. SpaceX is developing a reusable rocket launching system for their Falcon 9 and Falcon Heavy launch vehicles. A second-generation VTVL design was announced in 2011.〔(【引用サイトリンク】url=http://www.breitbart.com/article.php?id=CNG.13fe8544a6e090af0506874197e65650.271&show_article=1 )〕〔 〕 The low-altitude flight test program of an experimental technology-demonstrator launch vehicle began in 2012, with more extensive high-altitude over-water flight testing planned to begin in mid-2013, and continue on each subsequent Falcon 9 flight.〔 〕 Non-rocket spacelaunch alternatives are at the planning stage, although it is known that some companies are developing actual launch platforms, such as the spanish zero2infinity with their rockoon-based launcher "bloostar". Launch vehicles are often classified by the amount of mass they can carry into orbit. For example, a Proton rocket can lift into low Earth orbit (LEO). Launch vehicles are also characterized by their number of stages. Rockets with as many as five stages have been successfully launched, and there have been designs for several single-stage-to-orbit vehicles. Additionally, launch vehicles are very often supplied with boosters supplying high early thrust, normally burning with other engines. Boosters allow the remaining engines to be smaller, reducing the burnout mass of later stages to allow larger payloads. Other frequently-reported characteristics of launch vehicles are the launching nation or space agency and the company or consortium manufacturing and launching the vehicle. For example, the European Space Agency is responsible for the Ariane V, and the United Launch Alliance manufactures and launches the Delta IV and Atlas V rockets. Many launch vehicles are considered part of a historical line of vehicles of same or similar name; e.g., the Atlas V is the latest Atlas rocket. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Launch vehicle」の詳細全文を読む スポンサード リンク
|