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 编辑
Atmospheric entry 编辑
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.[1][2]
As a rough rule of thumb, 15% of the landed weight of an atmospheric reentry vehicle needs to be 防熱盾ing.[3]
航天飞机隔热系统s (TPS) can be made of a variety of materials, including reinforced carbon-carbon and 再入.[4] 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.[5]
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 LI-900 material was used on the Space Shuttle.
Landing and refurbishment 编辑
Spacecraft that land horizontally on a runway require wings and undercarriage. These typically consume about 9-12% of the spacecraft mass,[來源請求] which either reduces the payload or increases the size of the spacecraft. Concepts such as 舉升體 offer some reduction in wing mass,[來源請求] 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.[6][7]
可重複使用航天器列表 编辑
美國和歐洲太空總署
编辑
活躍 编辑
發展階段 编辑
已退役 编辑
- 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 编辑
俄羅斯 
苏联
编辑
發展階段 编辑
已取消 编辑
其它 编辑
發展階段 编辑
已取消 编辑
參見 编辑
參考 编辑
- ^ Dragon – Spacecraft & Satellites. [2020-05-31]. （原始内容存档于2023-02-09） （美国英语）.
- ^ Coming Up: Crew Dragon Deorbit Burn – Commercial Crew Program. blogs.nasa.gov. [2020-05-31]. （原始内容存档于2023-02-09） （美国英语）.
- ^ Chung, Winchell D. Jr. Basic Design. Atomic Rockets. Projectrho.com. 2011-05-30 [2011-07-04]. （原始内容存档于2020-04-13）.
- ^ Johnson, Sylvia. Thermal Protection Materials: Development, Characterization, and Evaluation (PDF). NASA Ames Research Center. September 2012 [2023-02-09]. （原始内容存档 (PDF)于2020-04-13）.
- ^ High emissivity coatings on fibrous ceramics for reusable space systems （页面存档备份，存于互联网档案馆） Corrosion Science 2019
- ^ Thompson, Loren. SpaceX Abandons Plan To Make Astronaut Spacecraft Reusable; Boeing Sticks With Reuse Plan. Forbes. [2020-05-31]. （原始内容存档于2023-02-09） （英语）.
- ^ SpaceX launches Dragon as it prepares for next cargo contract. SpaceNews.com. 2019-07-25 [2020-05-31] （美国英语）.