发射台 发射台是一种设计为发射火箭能驱动飞行器的地面设施包括运载火箭航天飞机弹道导弹等在内可用于固定和支撐火箭並为火箭和载荷提供维护支持發射台大致可分為固定式發射台和移動式發射台其中移動式發射台可以在公路或铁路上进行移動 大多数发射台都包括固定的服务结构以提供一个或多个进入平台来组装检查和维护运载工具并允许进入航天器包括装载机组人员 该垫可以包含火焰偏转结构以防止火箭排气的强热损坏飞行器或垫结构并且可以采用喷洒大量水的声音抑制系统 该垫也可以受到避雷器的保护 航天发射场通常包括多个发射场和其他支持基础设施 已隱藏部分未翻譯内容歡迎參與翻譯 Most launch pads include fixed service structures to provide one or more access platforms to assemble inspect and maintain the vehicle and to allow access to the spacecraft including the loading of crew The pad may contain a flame deflection structure to prevent the intense heat of the rocket exhaust from damaging the vehicle or pad structures and a sound suppression system spraying large quantities of water may be employed The pad may also be protected by lightning arresters A spaceport typically includes multiple launch complexes and other supporting infrastructure The launch complex for liquid fueled rockets often has extensive ground support equipment including propellant tanks and plumbing to fill the rocket before launch Cryogenic propellants liquid oxygen oxidizer and liquid hydrogen or liquid methane fuel need to be continuously topped off ie boiloff replaced during the launch sequence countdown as the vehicle awaits liftoff This becomes particularly important as complex sequences may be interrupted by planned or unplanned holds to fix problems Most rockets need to be supported and held down for a few seconds after ignition while the engines build up to full thrust The vehicle is commonly held on the pad by holddown arms or explosive bolts which are triggered when the vehicle is stable and ready to fly at which point all umbilical connections with the pad are released