飛行的N種可能

當(dāng)飛機制造商不斷通過“拉長”機身、提高燃油效率為飛機升級換代時，

一些或許會徹底改變飛行生活的概念飛機、飛行設(shè)備已經(jīng)悄然問世。

空客旗下100%使用電能的飛機即將投產(chǎn)，

完全利用太陽能進(jìn)行晝夜不間斷飛行的飛機也吸引了諸多飛行愛好者的關(guān)注，電動汽車特斯拉的總裁馬克斯試圖打造舒適、安全的飛行汽車，

德國人正在研制用意念就能操控飛機的飛行控制系統(tǒng)……

在不久的將來，

這些新技術(shù)或許會將公務(wù)機、民航的發(fā)展引入全新的領(lǐng)域，

甚至改變?nèi)藗儗︼w行的理解。

When aircraft manufacturers are upgrading their aircraft with extended fuselage or improved fuel efficiency， some concept aircraft or flying equipment that may fundamentally change our flying lives are quietly being developed. The 100% electric aircraft from Airbus will soon hit the market； a solar-powered aircraft that could fly day and night has been launched； the CEO of Tesla is building a safe and comfortable flying car； the German is developing a mind-controlled flight system … In the near future， these new technologies will be bringing business jets and civil airliners to brand new levels， or even change our perception of flying.

交通領(lǐng)域的能源消耗一直是困擾各國的重要問題，尤其以航空業(yè)為甚。根據(jù)一份世界能源署發(fā)布的數(shù)據(jù)顯示，空中交通約占全球碳排放總量的2.2%，且該數(shù)字正在不斷升高，如不采取行動，預(yù)計到2020年航空業(yè)的碳排放量將達(dá)到8億噸，2050年會占據(jù)全球排放總量的10%。

汽車界新能源利用開展得如火如荼，航空業(yè)也緊隨其后，越來越多的企業(yè)開始開發(fā)利用生物能源、氫燃料等新能源的飛機，其中一些甚至已經(jīng)成功翱翔天空。或許只欠成本降低、技術(shù)成熟的東風(fēng)，這些飛機就能借新能源的利箭，在環(huán)保的戰(zhàn)役中攻城拔寨。

在新能源飛機中，除了通常的節(jié)能環(huán)保、效率高之外，電動飛機具有獨特的優(yōu)勢。其由于電機作用，噪聲和振動水平很低，是降低此類污染的絕佳選擇。此外，電動飛機還更安全可靠，杜絕了燃油泄漏等事故隱患，而且結(jié)構(gòu)簡單、操作更加簡便，維修也相對易行，費用經(jīng)濟。另外，電動飛機可以獲得更佳的設(shè)計效果，采用創(chuàng)新布局，滿足特殊需求。

今年4月25日，空客公司在法國波爾多舉行了“電動飛機日”活動，旗下E-Fan電動飛機首次公開演示飛行。

這款由空客公司旗下的歐洲航空防務(wù)與航天集團（EADS）和法國航空制造商ACS公司聯(lián)合開發(fā)的雙座純電動飛機，由韓國Kokam公司制造的兩組250V鋰離子聚合電池供電，這些電池被安排在機翼內(nèi)側(cè)部分，充滿電只需要1小時。如果在空中電量耗盡，機載備用電池可供緊急降落。

空客公司首席技術(shù)官讓·博迪（Jean Botti）表示：“這款飛機的推出代表我們的技術(shù)發(fā)展邁出了戰(zhàn)略性的一步，我們還將致力于開發(fā)對國防以及民用有益的技術(shù)。”這位前通用汽車電動汽車研發(fā)團隊的工程師，對E-Fan的前景侃侃而談，并解釋其實際上是在為今后開發(fā)用于70～90座支線客機的混合動力發(fā)動機做技術(shù)儲備。在他看來，在電氣化技術(shù)普惠的今天，電動飛機夢變得不再遙遠(yuǎn)，航空業(yè)的改革與創(chuàng)新很可能從電氣化開始。EADS曾領(lǐng)導(dǎo)研發(fā)4引擎電動飛機Cri-Cri的負(fù)責(zé)人伊曼紐爾·朱伯特（Emmanuel Joubert ）也表達(dá)了同樣的看法，他說：“今天，電力驅(qū)動是相當(dāng)好的應(yīng)用技術(shù)，比如電動汽車。”

事實上，這種動力系統(tǒng)和電混動力汽車的原理基本一致，在動力需求最大的起飛階段，電池和電力發(fā)動機將為渦扇機提供全部的動力；等平穩(wěn)飛行時，電力發(fā)動機在保證渦扇動力的同時，可將一部分多余的電力儲存進(jìn)電池。

目前，E-Fan的續(xù)航時間并不長，只能支持實際飛行半個小時左右，但空客認(rèn)為這并不是問題，因為其主要用于試驗或者執(zhí)行任務(wù)的短途飛行、飛行員的特技飛行表演以及初學(xué)者的飛行訓(xùn)練。

博迪樂觀地預(yù)測，等它的技術(shù)足夠成熟，并且能夠批量生產(chǎn)，就可以將它推銷到飛行學(xué)校或特技表演隊。“我們將最快于2017年年底在法國西南部的波爾多工廠生產(chǎn)E-Fan。”他說。或許，在不久的將來，我們就可以在航校里一窺它的風(fēng)采，并且駕駛它學(xué)習(xí)飛行技術(shù)了。

太陽能已經(jīng)是外太空飛行器最基本的能源，在大氣層以內(nèi)，技術(shù)人員也正在嘗試讓它挑戰(zhàn)空氣阻力與地心引力，為飛機提供強大的動力。1981年7月7日，第一架以太陽能為動力的飛機——美國“太陽挑戰(zhàn)者”號，以平均每小時48千米的速度、3350米的飛行高度，完成了全長265千米的旅行，成功跨越英吉利海峽。如今，將太陽能視為一種成熟的空中能源還為時過早，但將它作為一種未來的高效能源，在新能源飛機研發(fā)中已越來越多地被提及。

近日，瑞士飛行員安德烈·博爾施伯格（André Borschberg）在瑞士駐華使館介紹了該公司新一代太陽能飛機 “陽光動力2”號。他將于2015年駕駛這款飛機進(jìn)行環(huán)球飛行。這款飛機克服了太陽能飛機天生的弱點——夜間飛行，使得“永久”航行成為可能。

夜間飛行是太陽能飛機最核心的性能體現(xiàn)，同時也是其最難逾越的技術(shù)障礙。“如果太陽能儲備不能支持夜晚飛行，那么飛機就會因喪失動力而墜落。”在博爾施伯格看來，陽光動力號已經(jīng)基本解決了這一問題。“為了能夠?qū)崿F(xiàn)真正的晝夜不停飛行，這就要求飛機的能效必然非常的高。”為了裝更多的電池，“陽光動力2”號飛機翼展達(dá)到72米，比傳統(tǒng)最大飛機波音747-81更寬。在白天飛行的時候，太陽能電池板從太陽中汲取能量，可以飛到接近9000米的高度，飛得越久，電池儲能就越多。

“陽光動力號（Solar Impulse）兼具科學(xué)及創(chuàng)新意義，同時也具有一定的哲學(xué)意義，它將提升社會大眾共同保護地球資源的意識。”伯特蘭·皮卡德（Bertrand Piccard）表示。陽光動力公司正是這位傳奇人物在十多年前與博爾施伯格共同創(chuàng)立的。他們在2009年6月制造出首架太陽能飛機。

2010年，陽光動力號成為全球首架實現(xiàn)26小時晝夜飛行的太陽能飛機，并在2011年和2012年先后完成跨國和跨洲飛行。2013年5月3日，陽光動力號從美國加利福尼亞州出發(fā)，途中在亞利桑那、德克薩斯、密蘇里、俄亥俄和華盛頓特區(qū)停留，最后在紐約完成飛行。這次飛行是歷史性的，也為兩人能夠繼續(xù)在太陽能飛機領(lǐng)域創(chuàng)造奇跡增加了信心與籌碼。

該項目目前由80位跨學(xué)科團隊專家、90個合作伙伴、100位左右顧問組成，項目經(jīng)過12年的分析、設(shè)計、計算、模擬、制造和測試，已經(jīng)投資1.7億美元。盡管中國太陽能企業(yè)已經(jīng)縱橫捭闔于全球，但是12年來，該項目并未有中國企業(yè)的加入。這也是吸引博爾施伯格來到中國的原因之一。“我們還在不斷尋找合作伙伴，如果有中國企業(yè)參與，我們當(dāng)然可以開展多種合作。”他說。

現(xiàn)在，在陽光動力號中應(yīng)用的一些新技術(shù)也在現(xiàn)有產(chǎn)業(yè)中得到了體現(xiàn)。“比如飛機飛到高空的時候艙外的溫度是零下40攝氏度，我們必須采用最先進(jìn)的隔熱材料，使熱量散發(fā)降到最低，這樣才能使能效達(dá)到最高。這種技術(shù)現(xiàn)在已經(jīng)用在制造冰箱上。還有很多其他的應(yīng)用，都可以從陽光動力號延伸到其他領(lǐng)域。”博爾施伯格說。

皮卡德希望在他的嘗試下，人們可以認(rèn)識到如果連飛機都可以拒絕依賴石油，成功繞行地球一周，那么就沒有人敢說，替代能源對于其他交通工具是不可實現(xiàn)的。博爾施伯格則認(rèn)為，陽光動力號不是為了載人，而是為了傳遞消息，為了向人們展示利用清潔能源我們可以做什么，一切都源于夢想、激情和熱愛。這樣一次冒險必須通過使用清潔技術(shù)，激發(fā)社會熱情，使公眾直面我們這個時代所面臨的各種挑戰(zhàn)。用他的話來說就是：“如果今天不開始，那么永遠(yuǎn)都不會走入明天。”

有專家預(yù)計，40多年后，在解決了太陽能吸收、大幅提高電池功效之后，能夠承載300名乘客的大型太陽能飛機有望投入運營。

當(dāng)安德烈·博爾施伯格在太陽能飛機領(lǐng)域積極奔走時，他的好朋友——特斯拉公司CEO艾隆·馬斯克（Elon Musk）不僅試圖用電動汽車改變世界，也聲稱要打造能廣泛應(yīng)用于大眾生活的飛行汽車。“我們顯然可以造出一輛飛行汽車——但那并非難點。真正的難點在于，怎樣讓這輛飛行汽車具備卓越的安全性和安靜性。原因是倘若這輛汽車聲音隆隆，那么會使人不開心。”

雖然馬斯克的宏愿尚未真正付諸實踐，但他指出了飛行汽車用于生活的兩大問題——安全性和舒適性，如果誰能有效解決這兩個問題，就能搶占先機，將扁平化的汽車世界打造得更加立體。美國航空業(yè)分析師羅伯特·曼恩說，從上世紀(jì)30年代起，人們就念叨著想開車飛上天了，發(fā)明者們也在不斷為此努力。顯然，這個愿望從未像今天這樣切近。

與馬斯克現(xiàn)在只是過嘴癮不同的是，位于美國馬薩諸塞州的Terrafugia公司正在開發(fā)一款名為Transition的兩座小型“飛機”。這款“飛機”不但擁有可折疊的機翼，而且擁有能夠在公路上奔馳的車輪。

在路面擁堵已經(jīng)成為社會常態(tài)的今天，仰望天空，若有一架如《神盾特工局》中“勞拉”一般的飛車呼嘯而過，相信任何人都會對它垂涎三尺。只不過電視劇中是特技效果，Transition卻能讓夢想照進(jìn)現(xiàn)實。

Transition在2009年試飛成功，它能夠在30秒內(nèi)由行駛模式變換為飛行模式，并實現(xiàn)100千米/小時的飛行速度，最遠(yuǎn)能夠飛行700多千米。它的發(fā)明者卡爾·迪特里希（Carl Dietrich）博士是麻省理工學(xué)院（MIT）航空航天部的研究員，他從2006年開始研發(fā)Transition汽車。“當(dāng)我說我在研究飛行汽車時，人們總會發(fā)出譏笑聲，但是事實上我真的是很認(rèn)真地在致力于此。”卡爾說。

因為供應(yīng)商及生產(chǎn)線等問題，Transition一再推遲交付時間，卡爾在2013年、2014年兩度來中國尋找合作者，他在中國的代理人——絲翼航空總裁張弩也陪同他四處奔走，以期獲得第五輪融資的款項、可供量產(chǎn)的制造商或其他技術(shù)支持。

在張弩看來，飛行汽車有著廣闊的前景，當(dāng)城市道路成為巨大的停車場時，似乎只有離開地面才是真正的解決之道。“Transition不僅獲得了美國聯(lián)邦航空管理局關(guān)于輕型運動飛機的許可，還獲得了美國國家公路交通安全管理局的認(rèn)證。雖然在國內(nèi)，走完這些流程、手續(xù)會非常困難，但我相信飛行汽車的社會效益將會非常好，我們也希望能夠有合作者在這些方面提供幫助。”她說。

《私人飛機》：您發(fā)明飛行汽車的初衷是什么？

卡爾：飛行汽車可以讓人們掌控自己的出行時間表，能夠更快、更安全地到達(dá)目的地，比目前的日常出行更加有效率，我認(rèn)為它擁有巨大的社會潛力。

《私人飛機》：何時飛行汽車能夠大規(guī)模量產(chǎn)？它的售價是多少？現(xiàn)在有多少訂單？

卡爾：Transition目前擁有100架訂單，我們將在2016年的第二季度交付第一批產(chǎn)品，其基本價格為27.9萬美元（約合173萬元人民幣）。

《私人飛機》：Transition如何保證它的安全性能？

卡爾：Transition具有全球衛(wèi)星定位系統(tǒng)、電子計算機自控系統(tǒng)以及衛(wèi)星控制技術(shù)等高端科技裝備，駕駛員無須掌握像飛機飛行員那樣的高難駕駛技術(shù)。但在駕駛Transition之前需要有20小時以上的飛行訓(xùn)練。

新一代產(chǎn)品中的計算機還可以幫用戶從數(shù)據(jù)網(wǎng)絡(luò)中規(guī)劃一條合適的飛行路徑，以規(guī)避其他空中飛行器和障礙。用戶只需要練習(xí)并掌握何時何地安全起降，對緊急情況做出反應(yīng)，在緊急情況下，只需知道如何拉動手柄開啟降落傘系統(tǒng)等基礎(chǔ)知識即可。

《私人飛機》：哪些人會喜歡飛行汽車？

卡爾：我們這款飛行汽車的售價略低于傳統(tǒng)的兩座飛機，和法拉利等超跑持平，我想我們的客戶有注重實用性的，因為Transition使用的是普通無鉛汽油，能耗低且使用方便；另外還有客戶是注重娛樂性的，駕駛飛行汽車相當(dāng)酷炫。在一般情況下，我們的客戶應(yīng)該是喜好自由的，向往靈活、有趣產(chǎn)品的。

《私人飛機》：Transition需要在一條至少500米的跑道上起飛，這是它的限制所在，對這點如何改進(jìn)？

卡爾：我們的下一代產(chǎn)品——TF-X是一款可以垂直起飛和降落的車輛，它所能應(yīng)用的地點將更為廣泛。但是飛機垂直起降時需要大量的空氣來助推或緩沖，動力氣流會對周邊的汽車造成破壞，所以TF-X起降大致需要網(wǎng)球場般大小的地方。另外，TF-X還要實現(xiàn)電和燃油的混合動力驅(qū)動以及實現(xiàn)智能自動駕駛等。TF-X大約需要8～10年的研發(fā)。

Transition的問題標(biāo)簽

噪音：Transition采用飛機的噪音標(biāo)準(zhǔn)，無法達(dá)到汽車般的環(huán)保性和舒適性。

起降跑道：美國聯(lián)邦航空管理局規(guī)定其必須在通航機場起降，在美國除了個別州，均對飛機的起降地點有限制，更不用提中國了。而且，Transition盡管賣點之一是解決擁堵問題，但跑道長度的限制注定這是一項不可能完成的任務(wù)。

證件與牌照：在中國，Transition必須具有飛機牌照和汽車牌照，遵從兩種產(chǎn)品的市場管理，駕駛者也必須擁有飛機駕駛牌照和汽車駕駛牌照。在政府監(jiān)管層面，這還是一項空白，一切需等2016年產(chǎn)品量產(chǎn)之后才能確定。

荷蘭PAL-V歐洲公司設(shè)計制造的個人空地兩用車PAL-V（personal air and land vehicle）一號，也是目前具有代表性的一款飛行汽車，它的起飛距離約200米。與Transition不同的是，它是由3個車輪帶動在路面上行駛的，飛行則通過安裝在身后的螺旋槳進(jìn)行驅(qū)動，并依靠頭頂上的水平旋翼提供升力，完成起飛。

三輪的造型讓PAL-V像一輛越野摩托車，巨大的旋翼又昭示它有直升機的基因。PAL-V在路面的實際操控介乎摩托車和賽車之間，共有兩個座椅，底盤采用傾斜設(shè)計，速度可達(dá)到每小時180千米。PAL-V在陸地上行進(jìn)時，旋翼會自動折疊收攏，降低阻力，因此速度很快。

這款飛行汽車的可折疊旋翼可保證駕駛和著陸的安全性。與普通直升機不同，飛行汽車的葉輪在空中只需空氣動力即可旋轉(zhuǎn)。即使發(fā)動機在空中出現(xiàn)故障，頂部的葉輪也可繼續(xù)旋轉(zhuǎn)，使飛行汽車平穩(wěn)降落而非突然下墜。GPS定位系統(tǒng)和雷達(dá)系統(tǒng)可保證其在空中的安全性。

飛行汽車的發(fā)明人約翰·巴克說：“這是輛很炫的車。在基礎(chǔ)設(shè)施建設(shè)不完善的國家和地區(qū)，飛行汽車比普通交通工具更安全快捷。在發(fā)達(dá)地區(qū)，它則可以幫人們省下大量堵在路上的時間。”PAL-V公司希望在未來這款飛機可以用于任務(wù)執(zhí)飛，如緊急服務(wù)和商業(yè)監(jiān)管，而不是用于私人領(lǐng)域。

與Transition相同的是，這款飛行汽車的量產(chǎn)時間也一再延后，但可喜的是，在7月15日，它正式鳴鑼開賣，售價29.5萬美元（約合人民幣183萬元）

從去年開始，可穿戴設(shè)備就成為了科技界最熱門的話題之一。像Google的“Project Glass”眼鏡，集智能手機、GPS、相機于一身，在用戶眼前展現(xiàn)實時信息，只要通過眼部動作就能拍照上傳、收發(fā)短信、查詢天氣路況，不必用手操控，就能記錄資訊。雖然可穿戴設(shè)備市場方興未艾，但是與智能手機一樣，在未來或許會迎來爆發(fā)式的增長，畢竟，電子設(shè)備生產(chǎn)的規(guī)模化使得這些產(chǎn)品的開發(fā)、量產(chǎn)成本較低，并能快速融入現(xiàn)有社會生態(tài)。

如今，這股旋風(fēng)也吹到了航空業(yè)，由于可穿戴設(shè)備可以很大程度上解放雙手，所以在飛機駕駛、維修等操作中都能得到有效利用，能夠讓操作者獲得更大的自由度，來掌控更多事務(wù)。如果智能設(shè)備更多地走進(jìn)機艙，那么我們未來的飛行體驗將會更加安全與智能，只需基礎(chǔ)的操作技能，即使不經(jīng)過專業(yè)的飛行訓(xùn)練，普通人也可以徜徉天空，方便得就像駕駛一輛私人轎車。

在天氣不佳時，飛行員的外界視野狀況讓飛機降落變得危險，但是Skylens可以改善這種狀況，Elbit Systems公司開發(fā)的這款頭戴顯示屏設(shè)備能夠獲得更加清晰的視野空間。

這款設(shè)備像一個笨重的滑雪鏡，但是它能優(yōu)化飛行視覺系統(tǒng)，在飛行員眼前顯示跑道和地平線數(shù)據(jù)，可以讓飛行員提高安全意識，增強其對飛行狀況的控制，提高起飛和降落的性能，比起其他的CRT、LCD顯示器，它使用更加方便。

該系統(tǒng)目前處于預(yù)先適航認(rèn)證階段，計劃將在2016年底服役。

也許在若干年后，駕駛飛機會是簡單而輕松的工作。飛行員只需戴上頭盔，將目光集中在跑道上，就能夠用意念駕駛飛機。或許聽起來遙不可及，然而現(xiàn)實中，相關(guān)研究已經(jīng)在進(jìn)行。

在德國慕尼黑理工大學(xué)和柏林工業(yè)大學(xué)共同研發(fā)出的意念飛行設(shè)備的飛行測試中，飛行員只需戴上“意念頭盔”，就能用他們的意念操控飛機。這種頭盔能夠讀取來自佩戴者大腦的電波信號，而后利用專門的算法將信號轉(zhuǎn)化成電腦指令。測試中，有不同飛行經(jīng)驗的7人在飛行模擬器中，其中一個人沒有任何駕駛飛機的經(jīng)驗，很顯然，他們可以精確地進(jìn)行導(dǎo)航，并通過飛行駕駛執(zhí)照考試。

“這是由歐盟支持的Brainflight項目，我們的愿景是讓更多的人能夠加入飛行行列中，”慕尼黑理工大學(xué)該項目負(fù)責(zé)人——航空工程師蒂姆·弗里克（Tim Fricke）解釋道，“讓大腦控制飛行，會讓飛行這件事變得更加容易。 這將減少飛行員的工作負(fù)荷，從而提高飛行安全。飛行員將會有更多的自由在駕駛艙管理其他事務(wù)。”

雖然這個令駕駛飛機變得更容易的技術(shù)才剛剛起步，但它似乎預(yù)示了駕駛飛機的門檻會越來越低。

New Energy Powered Aircraft

Energy consumption has been a Cvexing issue in the neck for the transportation industry， particularly for air transportation industry. According to the International Energy Agency， air transport currently accounts for 2.2% of the global carbon dioxide emission. Without drastic measures， the figure will continue to rise， reaching 800 million tons of emission by 2020， equals to 10% of the global total by 2050.

Already widely adopted in the auto industry， new energy has also found its way into the air transportation industry. Companies are developing new aircraft based on new energy such as bio-fuel or hydrogen fuel， some of which have completed test flying. As the technology matures and cost reduces， these aircraft will win the future aircraft market by their eco-friendly characteristics.

E-Generation — Electronic Aircraft

On 25 April 2014， Airbus debuted its electronic aircraft E-Fan on the “E-Aircraft Day” in Bordeaux， France. The two-seater electronic aircraft is jointly developed by EADS and Aero Composites Saintonge （ACS） and powered by two packs of 250V lithium battery made by Kokam. The batteries， which require one hour to be fully charged， are installed in the wings. In case they run out， built-in spare batteries will provide enough power for an emergency landing.

“The introduction of the E-Fan electric aircraft represents another strategic step forward in EADS' aviation research. We are committed to exploring leading-edge technologies that will yield future benefits for our civil and defense products，” said Jean Botti， Chief Technical Officer （CTO）， at EADS. He explained that the E-Fan project will be paving the way for the development of future hybrid power 70-90 seater regional jet. He believed that the future of E-aircraft is not far away and that the reform and innovation of the aviation industry will start with electrification. Emmanuel Joubert， leader of the four engine electronic aircraft project at EADS expressed similar optimisim， “Electric power is alrealy a well applied technology， as in electric cars.”

The electric power system of E-Fan works basically in the same way as a hybrid car. During takeoff， the batteries and the generator will provide power for the turbofan， and at cruise speed， the generator will store surplus electricity into the batteries while powering the turbofan.

E-Fan can only fly for half of an hour， but Airbus is not worried about its applicability， as it can be used for test flight， short haul mission， training， or acrobatic flight.

According to Jean Botti， as the technology matures for mass production， the aircraft can be sold to training schools or acrobatic pilots. “E-Fan will be produced earliest in 2017 in our facility in Bordeaux， France.” Perhaps in the very near future， we would be able to find and fly the aircraft in a training school.

Pursuing the Sun — Solar-Powered Aircraft

In the outer space， solar energy is already the main power for spacecraft. Within the atmosphere， researchers are now trying to leverage the energy to power aircraft. On July 7th， 1981， the first solar-powered aircraft- Solar Challenger， crossed the English Channel for a 165km journey at 11，000 feet and 30 miles/h. It is still premature for the universal application of solar power in air transport， but it is increasingly referred to as an important energy source in the discussions of new energy.

Recently， André Borschberg， a Swiss pilot and co-founder of Solar Impulse， introduced the Solar Impulse 2 to the Chinese audience in the Swiss Embassy to China. He announced that he will fly this aircraft on a round-the-world trip in 2015. The Solar Impulse 2 has overcome the biggest challenge to solar powered aircraft - night flight， making “perpetual flight” possible.

Night flight represents the core capability of solar-powered aircraft but also presents the biggest technical barrier. “If the stored solar power could not support night flight， the aircraft would fall out of the sky. To fly both day and night， the aircraft has to be very energy efficient.” The wingspan of Solar Impulse is extended to 72 meters， wider than that of Boeing 747-8I， in order to install more batteries. Solar battery panels will absorb energy during day flight at around 9，000 feet. The longer the flight， the more energy will be reserved.

“Solar Impulse is not only scientific and innovative， it is also philosophical. It will improve the public awareness of preserving the resources on earth”， said Bertrand Piccard， the legendary co-founder of Solar Impulse， which made the first solar-powered aircraft in June 2009.

In 2010， the aircraft achieved the first ever 26-hour flight by a solar-powered aircraft， followed by international flights in 2011 and inter-continental flights in 2012. On May 3， 2013， a Solar Impulse departed California， stopped over Arizona， Texas， Missouri， Ohio， and Washington， and arrived at New York. Success of the multi-stage flight renewed the two co-founders’s confidence in creating more miracles in the field.

Solar Impulse boasts of a multi-disciplinary team of 80 specialists from six countries， assisted by about 100 outside advisers and a 12-year history of analysis， design， computing， simulation， manufacturing， and testing. It has received an investment of 170 million USD from 90 partners， none of which from China despite the aggressive growth of Chinese solar energy companies around the world. But this is one of the reasons that draw André Borschberg to China. “We are still looking for partners， if Chinese enterprises want to be involved， we could surely conduct various cooperation.”

Today， the new technologies of Solar Impulse have found application in other industries. According to André Borschberg， “At high altitude， the temperature outside the aircraft is minus 40 degrees， we must use the most advanced heat insulating materials to minimize heat loss and to maximize energy efficiency. This technology has been applied to the making of fridges. There are many other examples where the technologies in Solar Impulse have been applied to other fields.”

Bertrand Piccard hopes that with his exploration， people can realize that if aircraft could fly around the world without oil， then nothing is impossible for alternate energy use in other transport vehicles. André Borschberg believes that Solar Impulse is not about carrying people， but about sending a message， demonstrating what we could do with clean energy. And it all started with a dream， a passion， and a love. In such an adventure， we have to use clean technology to inspire the public to face the challenges of our times. In his words， “If we do not start today， we will never get to tomorrow.”

Flying Cars

While André Borschberg is exploring solar-powered aircraft， his good friend， Elon Musk， CEO of Tesla， is tryin to the change the world with not only electric cars， but flying cars that can be used in everyday life.

\"We could definitely make a flying car， but that's not the hard part. The hard part is， how do you make a flying car that's super safe and quiet？ Because if it's a howler， you're going to make people very unhappy.\"

Although his ambition is yet to materialize， he has ponited out the two biggest challenges for mass producing flying cars —safetey and comfort. Whoever resolves the two issues could gain a first mover advantage in expanding the auto industry from two-dimensional to three-dimensional. According to Robert Mann， an airline industry analyst， the flying car has always had a special place in the American imagination. Inventors have been trying to make them since the 1930s. Today we have come closer than ever before we make it happen.

Fixed Wing – Transition

Unlike Telsa， the Massachusetts based company Teffafugia is already developing a two seat “aircraft” named Transition. With foldable wings， it is not only road worthy， but could also fly in the air.

As traffic jam is a norm today， a flying car like “Lola” in the Agents of Shield will draw the envious look from many. And Transition is turning that dream into reality.

Successfully test flied in 2009， Transition can turn from drive mode to flight mode within 30 seconds and reach a flight speed of 100km/h and a distance of 700 km. The designer of the car， Dr. Carl Dietrich， is a researcher at MIT Aerospace and Aeronautics. He started working on Transition since 2006， “When I said I was researching on flying car， people would just laugh it off， but I am really working on it.”

The delivery of Transition has been delayed time and again due to supplier and assembly line issues. Carl Dietrich has came to China in 2013 and 2014 looking for partners. President of its Chinese dealer， Silk Wings Aviation， Mrs. Zhang Nu， has been visiting around with him to get the fifth round of financing for its mass production and other technical support.

In Zhang Nu’s opinion， flying car has a promising prospect. When city streets become de facto parking lots， flying seems to be the only practical solution. “Transtion has not only obtained light aircraft certification from FAA， but also certification from NHTSA. Although it may take a long while for it to complete the proceduces in China， the flying car will bring huge social benefit. And we hope to get support from new partners.”

QA with Carl Dietrich

U-Jet： What motivates you to invent a flying car？

Carl： A flying car can help people control their own scheduel， get to their destinations faster， safer， and more efficient than current ways of transport. I think it has huge potential.

U-Jet： When can we expect its mass production？ What will be the price？ And how many orders have you got？

Carl： Transition now has an orderbook of 100. The first ones are to be delivered in the second quarter of 2016， and the base price is 279，000 USD.

U-Jet： How do you ensure the saftey performance of Transition？

Carl： Transition is equipped with GPS， a compute based auto control system， and a satellite control technology. Transition pilots are not required to master sophiscated manoeuvring skills like aircraft pilots， but they still need at least 20 hours of flight training.

The new generation computer could also help its user to plan an appropriate route based on its data network to stay away from other aircraft or barriers. Users only need to learn basic knowledge such as when and where to land safely. how to react to emergencies， and how to open the parachute system under urgent circumstances.

U-Jet： What kind of people would like flying cars？

Carl： Our flying car is priced lower than traditional two-seater aircraft and at the same level as Ferrai super cars. I think we will have customers who are cost-consious， as Transition burns usual unleaded gas， which is fuel efficient and convenient， and customers who look for entertainment， as it is cool to drive a flying car. Generally， our customers should be people who love freedom and look for flexible and fun products.

U-Jet： Transition needs at least a 500 meter runway to take off， how will you address this limitation？

Carl： Our next generation product—TF-X is a verticle take off and landing vehicle， so it can be used in various locations. But because the large amount of air required to provide lift for vertical take off and landing may cause damage to surrounding cars， a space with the size of a tennis court is recommended. In addition， TF-X will be an electric and fuel hyrid car with auto pilot capability. The development of TF-X will take 8-10 years.

Challenges Facing Transition

Noise and Emission： Applying the noise and emission standard of aircraft， Transition could not be as comfortable and environmental friendly as cars.

Runway： FAA requires the flying car to take off and land in GA airports. Except for a few states， there is strict limitations for aircraft take off and landing in the U.S.， not to mention in China. One of the selling points of Transition is its ability to address traffic jam， but the requirement on runway makes it impossible to operate.

Certification and License： In China， Transition has to obtain both aircraft certification and car license， abide by regulations of both markets， and requires its pilot to have both a pilot certificate and a driver’s license. Regulation on flying cars is not yet in place， which is not likely to change before its mass production in 2016.

Rotor Wing—PAL-V

PAL-V One is a roadable aircraft designed and made by a Dutch company PAL-V（personal air and land vehicle）. The aircraft requires 200 meters to take off， and unlike Transition， it runs on three wheels. The aircraft is powered by a tail rotor and a overhead rotor.

The three wheel PAL-V looks like a cross country motorcycle with helicopter features.

The two-seat tipping chassis PAL-V offers a mximun ground speed of 180km/h. The rotors could be retracted when not in use to improve aerodynamics and safety.

Unlike normal helicopters， the rotor of this flying car can continue operating with only aerodynamic force， which means， even if the engines shut down during flight， the rotor can still ensure a safety landing. The aircraft is also equipped with GPS and a radar system.

Its inventor John Bakker says： “It is a sleek car. In countries and regions where infrastructure is not well developed， flying car is safer and more convenient than normal vehicles. In developed areas， it could save people a lot of time on the road.” PLV hopes that the aircraft can be used for business missions such as emergency service or business surveillance， rather than for private use.

The delivery of the aircraft has also been postponed many times. Launched in 2006， prototype made in 2009， and test flied in 2012， the project has never met its target of marketing in 2012 and mass production in 2014. There is still no timeline for its time to the market.

Wearable Equipments

Common sense tells us that we have to be in some kind of equipment in order to overcome gravitiy and fly. But the advent of some electronic devices and wearable equipments has expanded the definition of flying. We can now either experience the feeling of flying on the ground or pilot an airplane with our minds. Smartphone has been playing an increasingly important role in our lives， will smart systems change our perception of flying as well？

Wearable Aircraft

The airline industry is also getting smarter. Smart gadgets like Google Project Glass， which is GPD， camera and smartphone all in one， for example， is used to send text messages， take and upload photos， search weather conditions， and record information during flight or maintenance. There are also many smart products designed specifically for flying.

Brainflight – Mind-Controlled Flying

In a few years， piloting an aircraft may become as easy as thinking commands. Simply put on an “mind control helmet”， and you will be able to pilot an aircraft with your thoughts.

In a test of the equipment jointly developed by the Technical University of Munich and the Technical University of Berlin， pilots can control an aircraft with their minds. Throught the helmet， the brain waves of the pilots are captured and converted through an algorithm to computer commands. In the test， 7 pilots， with varying degrees of experience， including one with no experience at all， controls and navigates with surprising accuracy.

“A long-term vision of the project is to provide more people access to fly，\" said Tim Fricke， the manager of this project at Technical University of Munich， \"through the brain control， fly could get easier. This would reduce the work load of the pilot， thereby increase security.\"

The technolgy is just taking off， but it may suggest that the threshold to become a pilot may be lowered over time.

Skylens— Wearable Head-up Display

Aircraft landing during bad weather may be dangerous as the vision of pilots could be impared. The Skylens wearable head-up display can prevent this with its enhanced flight vision.

According to its maker， Elbit System， Skylens can improve pilot safety awareness， enhance vision of surrounding environment， and improve performance during take off and landing with its enhanced fligth vision system，. It also offers more head space than other CRT or LCD.

The equipment can be retrofitted to any existing airplanes with a simple installation.