可重複使用的航天器

可重複使用航天器，顧名思義，是可重複使用的航天器，其設計須考慮重複發射、軌道、脫軌、大氣層再入。

可重複使用航天器的例子有太空飛機、航天飛機、航天飞机轨道器、逐夢者太空飛機、龙飞船的宇宙飞船。

此類系統的災難有：挑战者号航天飞机灾难、哥伦比亚号航天飞机灾难。

設計

Atmospheric entry 
Reusable spacecraft include mechanisms to deorbit and reenter the atmosphere in a controlled fashion. For this purpose, the 航天飞机 included 航天飛機軌道機動系統, and the 龙飞船 included its own engines, used for deorbiting. Deorbiting slows the spacecraft down, lowering its perigee to inside the atmosphere where the vehicle descends to Earth.

As a rough rule of thumb, 15% of the landed weight of an atmospheric reentry vehicle needs to be 防熱盾ing.

航天飞机隔热系统s (TPS) can be made of a variety of materials, including  and 再入.  Historically these materials were first developed on ICBM 多目標重返大氣層載具s. However, the requirements of reusable space systems differ from those of single use reentry vehicles, especially with regards to 防熱盾 requirements. In particular the need for durable high 发射率 coatings that can withstand multiple thermal cycles constitutes a key requirement in the development of new reusable spacecraft. Current materials for such high 发射率 coatings include transition metal disilicides.

Ablative heat shields are reliable, but they can only be used once, and are heavy. Reinforced carbon-carbon heat tiles like those used on the Space Shuttle are fragile, and this was proved on the Space Shuttle Columbia disaster. Making a resistant yet lightweight and effective heat tile poses a challenge. The  material was used on the Space Shuttle.

Landing and refurbishment
Spacecraft that land horizontally on a runway require wings and undercarriage. These typically consume about 9-12% of the spacecraft mass, which either reduces the payload or increases the size of the spacecraft. Concepts such as 舉升體 offer some reduction in wing mass, as does the 三角翼 shape of the 航天飞机轨道器.

垂直起降 (火箭) can be accomplished either with parachutes or propulsively. 龙飞船 was an example of 宇宙飞船 with parachute reusability. Its derivative, 龙飞船2号, was originally intended to propusively land on land. However, such concept of reusability was canceled in 2017 and now Dragon 2 uses parachutes to land in the ocean.

After the spacecraft lands, it may need to be refurbished to prepare it for its next flight. This process may be lengthy and expensive, taking up to a year. And the spacecraft may not be able to be recertified as human-rated after refurbishment. There is eventually a limit on how many times a spacecraft can be refurbished before it has to be retired, but how often a spacecraft can be reused differs significantly between the various spacecraft designs.

可重複使用航天器列表

和歐洲太空總署

活躍 
太空船2号
龙飞船2号
Crew Dragon
Cargo Dragon
新雪帕德火箭
X-37試驗機

發展階段 

SpaceX星艦
逐夢者太空飛機
波音星际航线
猎户座飞船

已退役 
 X-15試驗機
 双子座计划
 
航天飞机轨道器
發現號太空梭
挑戰者號太空梭（挑战者号航天飞机灾难）
哥倫比亞號太空梭（哥伦比亚号航天飞机灾难）
企業號太空梭（從未飛過太空）
亞特蘭提斯號太空梭
奮進號太空梭
龙飞船

已取消 
X-20試驗機
赫尔墨斯号航天飞机

暴風雪太空梭計畫軌道飛行器
暴風雪號穿梭機
小鳥號太空梭（從未飛過太空）
（從未飛過太空）
（從未飛過太空）
（從未飛過太空）

發展階段 
鹰宇宙飞船

已取消

其它 
新一代载人飞船
RLV-TD

發展階段 
阿凡達太空梭

已取消

參見 
 可复用发射载具

參考 

 
航天器