from spacefuture.com 譯/衛(wèi)偲
發(fā)展航天事業(yè)耗資巨大,但這絲毫沒有阻止人類對(duì)太空技術(shù)的探索與創(chuàng)新。太空技術(shù)未來(lái)的發(fā)展方向不僅是要將宇航員送上天搞科研,而且要將普通人送上天去旅行。為了實(shí)現(xiàn)這個(gè)目標(biāo),胸懷航天夢(mèng)的科學(xué)家與實(shí)干家們一直在努力,設(shè)計(jì)和制造了一系列針對(duì)太空旅行的航天器與運(yùn)載火箭。相信在不久的未來(lái),會(huì)有越來(lái)越多的普通人飛向太空,感受太空旅行的美妙。
In order for people to be able to travel economically to space, for space tourism and for other purposes, we need reusable launch vehicles. All commercial transport industries use reusable vehicles—and so will the commercial space transport industry. Luckily research aimed at developing low-cost reusable launch vehicles has increased recently. The following is a list of projects under way today.
Winner of the $10m Ansari X-Prize1), this suborbital2) passenger-carrying spaceplane was designed by Burt Rutan3)s Scaled Composites, famous for graphite4) composite and also the integrating contractor for the former Roton5). Following their successful bid6) to win the X-Prize, Scaled Composites are now turning their eyes to the next step: the development of a commercially viable passenger-carrying suborbital space vehicle.
SpaceShipOne features a rubber-nitrous oxide7) hybrid rocket engine and cold gas attitude8) control thrusters9); a graphite/epoxy10) primary structure; 3-place, sea-level, shirt-sleeve cabin environment; a low maintenance thermal protection system; and a unique feathered reentry system.
The spaceplane is carried under the belly of Scaled Composites White Knight carrier aircraft. The White Knight is a piloted, twin-turbojet11) research aircraft derived from the Proteus12) intended for high-altitude missions. Its first flight was on August 1, 2002. It provides a high-altitude airborne launch of SpaceShipOne. The White Knight is also equipped to flight-qualify13) all the SpaceShipOne systems except rocket propulsion. The aircrafts cockpit14), avionics15), life support systems, pneumatics16), trim servos, data system and electrical system components are identical to those installed in SpaceShipOne.
A passenger-carrying reusable SSTO17) VTOL18) rocket designed to carry 50 passengers to 200 km Earth orbit started as part of a study program by the Japanese Rocket Society. Since none of the space agencies of the world were studying how to make launch services available to the general public, the JRS started a Space Tourism Study Program in 1993, with the objective of getting the price of a flight to orbit down to around $10,000 per passenger. Work on Kankoh-maru has grown steadily in depth and breadth ever since, and has helped to accelerate the acceptance of space tourism as the direction for space development work today.
Spacebus is a design for a 2-stage passenger-carrying HTOL19) spaceplane by the company Bristol Spaceplanes in Britain. The first stage uses jet engines for take-off, followed by rocket engines to climb to high altitude for separation, after which the upper stage uses rocket engines to reach orbit. Using existing jet and rocket engines is very attractive in reducing initial development costs. And though new air-breathing rocket engines might be more efficient, theyre not needed initially.
Spacecab is a scaled-down version of Spacebus designed to carry 6 passengers. Its attractive as a first step to HTOL launch services since it uses only existing technology, and could start passenger operations much earlier than a vehicle requiring new engines to be developed.
SpaceXs Dragon is a small orbital spacecraft designed for transporting people and goods to and from the ISS20). It has two configurations21): an unmanned cargo configuration and a crew/passenger configuration capable of transporting up to seven people. It is built by a consortium22) led by SpaceX under NASAs Commercial Orbital Transportation Services (COTS) initiative. Dragon is also equipped with an ISS-compatible dock23) that is exposed through a removable nosecone24). Return to the Earths surface is achieved through a parachute-assisted splashdown25) and recovery.
Dragon is delivered into orbit on top of the Falcon 9 two-stage launch vehicle, an expanded version of the Falcon 1 rocket that completed a successful test launch to orbit on 28 September 2008 (after three prior failures). Both stages of the Falcon 9 are intended to be reusable.
The intended use for the combined vehicle is primarily to serve as a replacement for the shuttle fleet after their retirement, so space tourism is not an overt goal. Unlike vehicles aimed explicitly at the space tourism market, the Dragon/Falcon 9 combination is not fully reusable, and so is unlikely to withstand competition from a fully reusable orbital vehicle. However, until such time as such vehicles become available it may be the first privately financed space vehicle to be capable of delivering people, space tourists or otherwise, to orbit.
Xerus is a two-person reusable spaceplane proposed by XCOR Aerospace, which takes off and lands like a conventional aircraft. It is capable of climbing suborbitally to 100 km using a cluster of reusable rocket engines developed by XCOR. After a short period of weightless free fall the vehicle then re-enters the atmosphere. While the primary market for Xerus is space tourism, the vehicle is also being targeted at microsatellite delivery and suborbital science payloads.
XCORs Lynx, announced in March of 2008, is a follow-on design based on Xerus. Like Xerus, Lynx is a two-person suborbital spaceplane designed for the space tourism market but also aimed at science and research applications.
Thunderbird is a low cost fully reusable VTOL rocket from UK-based Starchaser Industries, which has an established track record26) in unmanned rocketry. It is an X-Prize contender, and is designed to carry three people on short suborbital pleasure flights into space.
The vehicle uses existing off-the-shelf27) components wherever possible to minimize development cost, combined with an advanced composite for the airframe. The primary propulsion is provided by LOX/kerosene engines28) which carry the vehicle to a maximum altitude of 100 km after burnout before re-entering tail-first using a steerable parasail29). Reaction control is handled independently by cold gas thrusters.
The Thunderbird is a single stage vehicle, but composed of two discrete and separable units: a command module, which includes the cabin, life support and reaction control system, and a propulsion module comprising the fuel tanks, engines and landing gear. In an emergency the command module is detachable from the rest of the vehicle, allowing the crew to be brought down independently.
Nova is a scaled-down version of Thunderbird designed to bridge the gap between previously flown unmanned rockets and Thunderbird. Standing at roughly two thirds of the height of its 52 feet larger sibling, Nova is designed to carry a single person into space to a maximum altitude of approximately 100 km. Although not an X-Prize contender due to its less than three-person capacity, Nova is intended to be the worlds first privately developed spaceship.
為了讓人們能夠以更經(jīng)濟(jì)的方式前往太空,進(jìn)行太空旅行或?qū)崿F(xiàn)其他目的,我們需要可重復(fù)使用的運(yùn)載器。所有的商業(yè)運(yùn)輸行業(yè)都使用可重復(fù)使用的運(yùn)輸工具,太空商業(yè)運(yùn)輸行業(yè)也將如此。幸運(yùn)的是,旨在開發(fā)低成本、可重復(fù)使用運(yùn)載器的研究最近已經(jīng)多了起來(lái)。下文列出的就是如今正在開展的一些項(xiàng)目。
這架亞軌道載客航天飛機(jī)是獎(jiǎng)金數(shù)額為一千萬(wàn)美元的安薩里X獎(jiǎng)的得主,由伯特·魯坦的縮尺復(fù)合材料公司設(shè)計(jì)。該公司以石墨復(fù)合材料著稱,并且是更早的航天器羅頓的集成承包商。在成功贏得了X獎(jiǎng)之后,縮尺復(fù)合材料公司現(xiàn)在把注意力轉(zhuǎn)向了下一步:開發(fā)一架商業(yè)上可行的亞軌道載客航天器。
太空船一號(hào)的主要特色如下:采用橡膠-氧化亞氮混合火箭發(fā)動(dòng)機(jī)和冷氣體姿態(tài)控制推進(jìn)器;采用石墨/環(huán)氧樹脂主結(jié)構(gòu);座艙可容納三人,具有海平面氣壓水平,在艙內(nèi)只穿襯衣即可;采用低維護(hù)熱防護(hù)系統(tǒng)和獨(dú)特的羽毛型再入系統(tǒng)。
這架航天飛機(jī)搭載于縮尺復(fù)合材料公司制造的運(yùn)載飛機(jī)白色騎士的腹下。白色騎士是一架有人駕駛的雙渦輪噴氣式研究用飛機(jī),其源頭可追溯至用于高空飛行任務(wù)的海神號(hào)飛機(jī)。白色騎士的首次飛行是在2002年8月1日。它能使太空船一號(hào)實(shí)現(xiàn)高空機(jī)載發(fā)射。白色騎士可以用來(lái)對(duì)太空船一號(hào)除火箭推進(jìn)系統(tǒng)外的其他所有系統(tǒng)進(jìn)行飛行資格測(cè)試。這架飛機(jī)配有與太空船一號(hào)完全一樣的駕駛員座艙、航空電子設(shè)備、生命支持系統(tǒng)、氣動(dòng)裝置、平衡伺服系統(tǒng)、數(shù)據(jù)系統(tǒng)以及電氣系統(tǒng)部件。
觀光丸是一枚可重復(fù)使用的單級(jí)入軌垂直起降載客火箭,其設(shè)計(jì)目的是將50名乘客運(yùn)載至200千米高度的地球軌道。該火箭最初是日本火箭協(xié)會(huì)一項(xiàng)研究計(jì)劃中的一部分。鑒于當(dāng)時(shí)世界上沒有一個(gè)太空機(jī)構(gòu)在研究如何為普通大眾提供發(fā)射運(yùn)載的服務(wù),日本火箭協(xié)會(huì)于1993年啟動(dòng)了一項(xiàng)太空旅行研究計(jì)劃,目標(biāo)是將飛往太空軌道的價(jià)格降至每位乘客一萬(wàn)美元左右。自那以后,觀光丸的研究工作在深度和廣度方面一直得以穩(wěn)步進(jìn)展,并且促使人們更快地接受了如下觀念:太空旅行是當(dāng)今太空開發(fā)工作的方向。
太空巴士是由英國(guó)布里斯托航天飛機(jī)公司設(shè)計(jì)的二級(jí)水平起降載客航天飛機(jī)。它的第一級(jí)采用噴氣發(fā)動(dòng)機(jī)起飛,然后利用火箭發(fā)動(dòng)機(jī)攀升至高空進(jìn)行分離。之后,上面一級(jí)使用火箭發(fā)動(dòng)機(jī)進(jìn)入軌道。使用現(xiàn)有的噴氣發(fā)動(dòng)機(jī)和火箭發(fā)動(dòng)機(jī)非常有吸引力,因?yàn)檫@樣能夠降低初始開發(fā)成本。雖然新型的吸氣式火箭發(fā)動(dòng)機(jī)可能更有效,但初始階段并不需要這樣的發(fā)動(dòng)機(jī)。
太空的士是太空巴士的縮小版,能夠攜帶六名乘客。作為實(shí)現(xiàn)水平起降發(fā)射服務(wù)的第一步,太空的士很有吸引力,因?yàn)樗鼉H使用現(xiàn)有技術(shù),與需要開發(fā)新發(fā)動(dòng)機(jī)的運(yùn)載器相比,它啟動(dòng)客運(yùn)業(yè)務(wù)的時(shí)間會(huì)提早很多。
太空探索技術(shù)公司的天龍?zhí)栵w船是一種小型軌道航天器,用于向國(guó)際空間站往返運(yùn)送人員和貨物。它包括兩部分構(gòu)造:無(wú)人駕駛貨運(yùn)構(gòu)造和運(yùn)載量可達(dá)七人的機(jī)組成員/乘客構(gòu)造。該航天器是由太空探索技術(shù)公司牽頭的幾家企業(yè)根據(jù)美國(guó)航空航天局的商業(yè)軌道運(yùn)輸服務(wù)(COTS)計(jì)劃建造的。天龍?zhí)栐诳刹鹦兜念^錐上配備有一個(gè)與國(guó)際空間站兼容的對(duì)接裝置。通過(guò)降落傘輔助濺落和回收的方式,飛船可返回地球表面。
天龍?zhí)栵w船搭載在獵鷹9號(hào)兩級(jí)運(yùn)載器上被送入軌道。獵鷹9號(hào)是獵鷹1號(hào)火箭的擴(kuò)大版,獵鷹1號(hào)在經(jīng)歷三次失敗之后于2008年9月28日成功地完成了發(fā)射至軌道的測(cè)試。獵鷹9號(hào)的兩級(jí)都采用了可重復(fù)使用的設(shè)計(jì)。
這套組合型運(yùn)載器的設(shè)想用途主要是在美國(guó)國(guó)家航空航天局的航天飛機(jī)退休后擔(dān)任替補(bǔ),所以太空旅行顯然并不是這一運(yùn)載器的目標(biāo)。與明確針對(duì)太空旅行市場(chǎng)的運(yùn)載器不同,天龍?zhí)柵c獵鷹9號(hào)的組合并不是能完全重復(fù)使用的,所以不大可能與能完全重復(fù)使用的軌道運(yùn)載器進(jìn)行競(jìng)爭(zhēng)。然而,在這類運(yùn)載器投入使用之前,天龍?zhí)柵c獵鷹9號(hào)的組合可能是第一個(gè)由私人投資的能將人類——太空游客或因其他目的前往太空的人——送入太空軌道的航天器。
齊羅斯是由XCOR宇航公司設(shè)計(jì)的可重復(fù)使用的雙人航天飛機(jī),可以像傳統(tǒng)飛機(jī)一樣起飛和降落。它能夠利用一組由XCOR設(shè)計(jì)的可重復(fù)使用的火箭發(fā)動(dòng)機(jī)攀升至100千米的亞軌道。在短時(shí)間的失重狀態(tài)下自由下落后,這個(gè)運(yùn)載器重新進(jìn)入大氣層。雖然齊羅斯的主要市場(chǎng)是太空旅行,但該運(yùn)載器也正在把目標(biāo)指向微衛(wèi)星發(fā)射和亞軌道科學(xué)載荷。
XCOR公司于2008年3月對(duì)外宣布的山貓航天飛機(jī)是基于齊羅斯的后續(xù)設(shè)計(jì)。與齊羅斯一樣,山貓也是亞軌道雙人航天飛機(jī),是針對(duì)太空旅行市場(chǎng)而設(shè)計(jì)的,但也打算用于科學(xué)研究。
雷鳥是英國(guó)追星者工業(yè)公司生產(chǎn)的一種低成本、可完全重復(fù)使用的垂直起降火箭,該公司以往在無(wú)人駕駛火箭領(lǐng)域具有良好的表現(xiàn)紀(jì)錄。雷鳥是X獎(jiǎng)的爭(zhēng)奪者之一,其設(shè)計(jì)目的是將三人送入太空的亞軌道進(jìn)行短暫的休閑飛行。
該運(yùn)載器盡可能使用現(xiàn)有的非定制組件,以使開發(fā)成本降到最低,同時(shí)使用了先進(jìn)的復(fù)合材料制作機(jī)身?;鸺闹魍七M(jìn)力由液氧/煤油發(fā)動(dòng)機(jī)提供,發(fā)動(dòng)機(jī)在燃料耗盡后可將火箭送達(dá)100千米的最大高度。之后火箭使用一個(gè)可操縱的滑翔傘以尾部先入的方式重返大氣層。火箭的反作用力控制則由冷氣體推進(jìn)器獨(dú)立完成。
雷鳥是一個(gè)單級(jí)運(yùn)載器,但包括兩個(gè)相互分離的獨(dú)立單元:一個(gè)是指揮艙,包括機(jī)艙、生命支持系統(tǒng)和反作用力控制系統(tǒng);另一個(gè)是推進(jìn)艙,包括燃料箱、發(fā)動(dòng)機(jī)和降落架。在緊急情況下,指揮艙可以與火箭的其余部分分離,將機(jī)組人員獨(dú)立帶回。
新星是雷鳥的縮小版本,旨在彌補(bǔ)以前使用的無(wú)人駕駛火箭與雷鳥之間的差距。新星的高度大約是其52英尺高的大個(gè)兄弟的三分之二。根據(jù)其設(shè)計(jì),新星可以將一個(gè)人送入太空,飛行的最大高度接近100千米。由于新星的運(yùn)載量不到三人,所以它無(wú)法參與X獎(jiǎng)的角逐,但新星的設(shè)計(jì)目標(biāo)是要成為世界上第一個(gè)私人開發(fā)的飛船。
1. Ansari X-Prize: 安薩里X獎(jiǎng),原名為X獎(jiǎng)(X Prize),設(shè)立于1996年5月,是為促進(jìn)私人載人航天技術(shù)的創(chuàng)新而設(shè)立的總額為一千萬(wàn)美元的航天大獎(jiǎng)。
2. suborbital [s??b??b?tl] adj. 亞軌道的
3. Burt Rutan:伯特·魯坦(1943~),美國(guó)著名的飛行學(xué)家和設(shè)計(jì)師,太空船一號(hào)的設(shè)計(jì)師,他于1982年創(chuàng)立了縮尺復(fù)合材料公司。
4. graphite [?ɡr?fa?t] n. [礦]石墨
5. Roton:羅頓,一款單級(jí)入軌、可重復(fù)使用和垂直降落的載人航天器,由一家名為“滾動(dòng)火箭”(Rotary Rocket)的公司設(shè)計(jì)與制造。該公司后來(lái)因?yàn)橘Y金短缺于2001年初倒閉。
6. bid [b?d] n. 努力,爭(zhēng)取
7. oxide [??ksa?d] n. [化]氧化物
8. attitude [??t?tju?d] n. [空] (飛行時(shí)的)姿態(tài)
9. thruster [?θr?st?(r)] n. 推進(jìn)器
10. epoxy [??p?ksi] n. [化]環(huán)氧樹脂,熱固樹脂的一種,尤用為表面涂料和黏合劑。
11. turbojet [?t??b??d?et] n. [空]渦輪噴氣飛機(jī)
12. Proteus:海神號(hào)飛機(jī),由縮尺復(fù)合材料公司推出的長(zhǎng)航時(shí)高空飛機(jī)
13. flight-qualify:對(duì)……進(jìn)行飛行資格測(cè)試,即對(duì)某一產(chǎn)品、過(guò)程或材料進(jìn)行測(cè)試,從而證明它能夠適應(yīng)太空飛行環(huán)境。
14. cockpit [?k?kp?t] n. 駕駛員座艙
15. avionics [?e?vi??n?ks] n. 航空電子設(shè)備
16. pneumatic [nju??m?t?k] n. 氣體力學(xué)設(shè)備
17. SSTO:?jiǎn)渭?jí)入軌,single stage to orbit的縮寫
18. VTOL:垂直起飛與著陸,vertical take-off and landing的縮寫
19. HTOL:水平起飛與著陸,horizontal take-off and landing的縮寫
20. ISS:國(guó)際空間站,International Space Station的縮寫
21. configuration [k?n?f?ɡ??re??n] n. 構(gòu)造
22. consortium [k?n?s??ti?m] n. 聯(lián)營(yíng)企業(yè),聯(lián)盟
23. dock [d?k] n. 空間對(duì)接
24. nosecone [?n??zk??n] n. (火箭或?qū)椀模╊^錐
25. splashdown [?spl??da?n] n. [空] (宇宙飛船的)濺落
26. track record:以往的記錄
27. off-the-shelf:(軍用產(chǎn)品等)現(xiàn)成的,非專門設(shè)計(jì)(或定制)的
28. LOX/kerosene engine:液氧/煤油發(fā)動(dòng)機(jī)
29. parasail [?p?r?se?l] n. 滑翔傘