英語沙龍十年合集珍藏版第三輯Vaunted1) Technology: Stealth2) Avionics3)

00:00

00:00

MP3下載 文本下載

https://online1.tingclass.net/lesson/shi0529/0000/977/44.mp3

https://image.tingclass.net/statics/js/2012

Vaunted¹⁾ Technology: Stealth²⁾ Avionics³⁾

Northrop Grumman Corp．（NGC）boasts⁴⁾ on its Web site the B－２spirit stealth bomber⁵⁾ is nearly invisible．Because the plane’s composite materials and bat－shaped design make it hard for radar⁶⁾ to pick up．However，in １９９９，an F－１１７，which also has a stealthy shape and materials，was blasted out of the sky over the Balkans．Stealth technology is hardly a sham．It shrinks the radar“signature”of a plane．If a conventional aircraft makes a blip on radar screens at ２００kilometers，a stealthy plane wouldn’ t appear until it was ３４km away．The point is，radar does eventually detect the plane．Weather can also present a problem．The B－２’s materials were tested at Edwards Air Force Base，where it rarely rains．But when the high－tech bombers got drenched⁷⁾ during missions in the Balkans，the tape used to fill seams in the composite skin often came loose．That en larges the radar signature．

□by Stan Crock

高科技神話：隱形航空電子技術(shù)

諾思羅普-格魯曼公司在自己的網(wǎng)站上吹噓說，“精靈”B-２隱形轟炸機(jī)幾乎是看不見的，因為該機(jī)的復(fù)合材料和蝙蝠形狀的設(shè)計使其難以被雷達(dá)發(fā)現(xiàn)。然而以相同形狀和材料制造的一架F-１１７戰(zhàn)斗機(jī)卻于１９９９年在巴爾干半島上空被擊落。隱形技術(shù)絕不是假的。它能縮小飛機(jī)在雷達(dá)屏幕上的信號特征。假如普通飛機(jī)在２００公里以外時在雷達(dá)屏幕上形成一個光點(diǎn)，那么隱形飛機(jī)要到３４公里時才會在雷達(dá)屏幕上顯現(xiàn)。問題是，雷達(dá)最終還是會發(fā)現(xiàn)飛機(jī)。天氣也會帶來問題。對B －２材料的測試工作是在很少下雨的愛德華茲空軍基地開展的。但當(dāng)該機(jī)在巴爾干半島執(zhí)行任務(wù)時，遭到雨淋后，用于填充復(fù)合材料外殼接縫的膠帶往往會松脫，從而擴(kuò)大了飛機(jī)的雷達(dá)信號特征。

NOTE 注釋：

1. vaunted [vC:ntid] 自夸的，吹噓的

2. stealth [stelW] n. 秘密行動

3. avionics [7eivi5Cniks] n. 航空電子技術(shù)

4. boast [bEust] v. 自夸，自吹

5. bomber [5bCmE] n. 轟炸機(jī), 轟炸員

6. radar [5reidE] n. 雷達(dá), 電波探測器

7. drenched [drentFt] adj.濕透的