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?yàn)樵摍C(jī)的復(fù)合材料和蝙蝠形狀的設(shè)計(jì)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(hào)特征。假如普通飛機(jī)在200公里以外時(shí)在雷達(dá)屏幕上形成一個(gè)光點(diǎn),那么隱形飛機(jī)要到34公里時(shí)才會(huì)在雷達(dá)屏幕上顯現(xiàn)。問題是,雷達(dá)最終還是會(huì)發(fā)現(xiàn)飛機(jī)。天氣也會(huì)帶來問題。對(duì)B -2材料的測(cè)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(shí),遭到雨淋后,用于填充復(fù)合材料外殼接縫的膠帶往往會(huì)松脫,從而擴(kuò)大了飛機(jī)的雷達(dá)信號(hào)特征。
NOTE 注釋:
1. vaunted [vC:ntid] 自夸的,吹噓的
2. stealth [stelW] n. 秘密行動(dòng)
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(cè)器
7. drenched [drentFt] adj.濕透的