The U.S. Air Force， unlike the Navy， was determined to improve bombing accuracy even during the Vietnam War. Before that conflict was over， it had developed and used the first of its guided-bomb systems1. This was used to good effect in attacking pinpoint2 targets that had previously resisted conventional attacks（and had gotten many Air Force bombers shot down3 by dense4 defenses）。 The Air Force continued working on better bombing systems throughout the l970s and l980s. This was an expensive proposition， but then， the Air Force spends more of its budget5 on research and development than the other services. The wisdom of this effort did not become obvious until the Gulf War6 when it was found that the Navy aircraft， lacking such systems， were much less effective.
To put this into perspective7， consider what it took—— in three wars， over the past fifty years—— to achieve a 90 percent probability8 of destroying a target measuring sixty feet by one hundred feet （a building， usually housing a headquarters， factory， or whatever）。 In the 1940s （World War II） this required 1，500 heavy bomber9 （B-17） sorties10 dropping 9，000 one-ton bombs （half of which would land more than 3300 feet from the target）。 In the 1960s （Vietnam） more accurate bombing systems allowed the same target to be destroyed with 176 jet fighter-bomber （F-4 Phantom11） sorties， each carrying one bomb （half of which would land more than 400 feet from the target）。 In the l990s （Iraq） this required one sortie by a light bomber （the F-117A Stealth12）， carrying a single one-ton bomb that will land within ten feet of where it is aimed.
A painful lesson from Vietnam was the high cost of attacking heavily defended targets. These losses could be reduced by sending along swarms13 of electronic warfare aircraft and bombers to destroy the enemy radars and antiaircraft14 weapons. Precision bombing systems also made the losses more tolerable15. The Air Force theorized that it would be even more efficient to develop aircraft that would be relatively invisible to enemy radar. Thus these " stealth" aircraft （designed to be nearly invisible to enemy radar） could go in alone and either bomb high-value targets or destroy the enemy air defenses. Also， when they were loaded with precision guided bombs， the Air Force would have a practically invulnerable16 bomber that would not only reduce friendly losses but also reduce the losses of enemy civilians. The first of these stealth aircraft was the F-117. Built in secret to deny potential opponents the opportunity to develop countermeasures17， the F-117 became operational in the early l980s and did not get its first real trial by combat until the Gulf War. While the F 117A was called the " stealth fighter" ， it was actually designed and used as a light bomber. The mission it was designed for was to penetrate18 thick Soviet air defenses in Central Europe and attack key targets and air defense systems （radars， command centers， and missile launchers）。 The Iraqi air-defense system was built with Soviet assistance and largely with Soviet equipment. The F-117A had little trouble dealing with it. Production of the initial batch19 of F-117As was completed in the late l980s.
Meanwhile， another " black" （secret） project， the B-2 bomber， was also built using stealth technology. The B-2 is an enormously expensive aircraft as it contains even more advanced stealth technology， carries much more weight in bombs， and has a much longer range. The cost of this program makes it difficult for the Air Force to justify building more than a handful of B-2s. The Air Force has other stealth projects that deal with reconnaissance20 work.
與海軍不同，美國空軍早在越戰(zhàn)期間就決心提高其轟炸精度。越戰(zhàn)結(jié)束前，空軍就研制并率先使用了制導(dǎo)炸彈系統(tǒng)。該系統(tǒng)用于攻擊定位精確的目標時的效果很好。這種目標先前難以用常規(guī)攻擊方式加以摧毀（空軍的許多轟炸機被密集的防空炮火所擊落）。在整個70年代和80年代，空軍一直在研制更好的轟炸系統(tǒng)。該項目耗資巨大?？哲娪糜谘芯颗c開發(fā)的經(jīng)費比其他軍種多。這樣做的高明之處直到海灣戰(zhàn)爭才顯露出來。當時，海軍的飛機由于沒有裝備這種系統(tǒng)，轟炸效果要差得多。
讓我們分析一下在過去50年里發(fā)生的3次戰(zhàn)爭，轟炸一個長100英尺寬60英尺的目標（通常是一幢可容納一個指揮所、一家工廠或其他單位的大樓），毀傷概率為90％，需要多少飛行架次和投擲多少炸彈：在40年代（二戰(zhàn)時期），需出動重型轟炸機（B-17）1500架次，投擲1噸重的炸彈9000枚（有一半炸彈偏離目標3300多英尺）；在60年代（越戰(zhàn)期間），由于使用更為精確的轟炸系統(tǒng)，摧毀同樣目標只需出動噴氣式戰(zhàn)斗轟炸機（F-4"鬼怪式"） 176架次，每架飛機攜帶1枚炸彈（其中一半炸彈偏離目標400多英尺）；在90年代（海灣戰(zhàn)爭期間），僅需一架輕型轟炸機（F-117A隱形飛機）出動 1個架次，該機只攜帶1枚1噸重的炸彈，炸彈將落在所瞄準目標的10英尺范圍之內(nèi)。
越戰(zhàn)中的一個慘痛教訓(xùn)是，空軍飛機攻擊敵嚴密防衛(wèi)的目標時傷亡慘重。要減少損失，可出動大批電子戰(zhàn)機和轟炸機摧毀敵人的雷達和防空武器。使用精確轟炸系統(tǒng)也可將損失減少到較能承受的程度?？哲姷睦碚撌牵l(fā)展那種使敵人雷達難以發(fā)現(xiàn)的飛機，是減少飛機和人員傷亡的更為有效的途徑。這樣，設(shè)計成幾乎讓敵方雷達看不到的"隱形"飛機，便可單機在有重要轟炸價值的目標區(qū)轟炸或摧毀敵防空體系。"隱形"飛機一旦裝有精確制導(dǎo)炸彈，空軍就擁有了一種實際上難以摧毀的轟炸機。這種飛機不僅能減少己方的傷亡，而且還能減少敵方平民的傷亡。第一種隱形飛機是F-117.為防止對手研制出對抗設(shè)施，F(xiàn)-117的生產(chǎn)十分保密。該飛機于80年代初開始投入使用，而首次真正接受作戰(zhàn)檢驗還是在海灣戰(zhàn)爭中。雖然F-117A被稱為"隱形戰(zhàn)斗機"，實際上它是被作為輕型轟炸機來設(shè)計和使用的。其任務(wù)是突入蘇聯(lián)在中歐的嚴密的防空體系，對重要目標和防空系統(tǒng)（雷達、指揮中心和導(dǎo)彈發(fā)射架）實施攻擊。伊拉克的防空系統(tǒng)是在蘇聯(lián)的幫助下建成的，所使用的裝備主要是由蘇聯(lián)提供的。F-117A型飛機對付它毫不費事。F-117A型飛機最初的批量生產(chǎn)完成于80年代末期。
與此同時，另一項采用隱形技術(shù)制造B-2轟炸機的"黑色"（秘密）計劃也已開始。B-2轟炸機由于使用了更先進的隱形技術(shù)，所以造價十分昂貴。該機的載彈量要大得多，航程也遠得多。昂貴的造價使空軍難以找出批量生產(chǎn)B-2轟炸機的充足理由?？哲娺€擬定了在偵察工作方面使用隱形技術(shù)的其他一些計劃。
注釋：
1.guided-bomb system 制導(dǎo)炸彈系統(tǒng)
2.pinpoint adj.[軍]定位精確的
3.shot down 擊落
4.dense adj.密集的，濃密的
5.budget n.預(yù)算拔款，?？?BR> 6.Gulf War 海灣戰(zhàn)爭
7.perspective n.視角，想法
8.probability n.[數(shù)]概率
9.heavy bomber 重型轟炸機
10.sortie vi.（軍用飛機）出動，出擊
11.phantom n.幽靈，[P-]鬼怪式飛機
12.stealth n.秘密行動[S-]隱形飛機
13.swarm n.蜂群，一大群
14.antiaircraft adj.防空的
15.tolerable adj.可容忍的
16.invulnerable adj.不會遭到攻擊的
17.countermeasure n.對策，反措施
18.penetrate vt.穿透，突破
19.batch n.一批生產(chǎn)量
20.reconnaissance n.偵察
To put this into perspective7， consider what it took—— in three wars， over the past fifty years—— to achieve a 90 percent probability8 of destroying a target measuring sixty feet by one hundred feet （a building， usually housing a headquarters， factory， or whatever）。 In the 1940s （World War II） this required 1，500 heavy bomber9 （B-17） sorties10 dropping 9，000 one-ton bombs （half of which would land more than 3300 feet from the target）。 In the 1960s （Vietnam） more accurate bombing systems allowed the same target to be destroyed with 176 jet fighter-bomber （F-4 Phantom11） sorties， each carrying one bomb （half of which would land more than 400 feet from the target）。 In the l990s （Iraq） this required one sortie by a light bomber （the F-117A Stealth12）， carrying a single one-ton bomb that will land within ten feet of where it is aimed.
A painful lesson from Vietnam was the high cost of attacking heavily defended targets. These losses could be reduced by sending along swarms13 of electronic warfare aircraft and bombers to destroy the enemy radars and antiaircraft14 weapons. Precision bombing systems also made the losses more tolerable15. The Air Force theorized that it would be even more efficient to develop aircraft that would be relatively invisible to enemy radar. Thus these " stealth" aircraft （designed to be nearly invisible to enemy radar） could go in alone and either bomb high-value targets or destroy the enemy air defenses. Also， when they were loaded with precision guided bombs， the Air Force would have a practically invulnerable16 bomber that would not only reduce friendly losses but also reduce the losses of enemy civilians. The first of these stealth aircraft was the F-117. Built in secret to deny potential opponents the opportunity to develop countermeasures17， the F-117 became operational in the early l980s and did not get its first real trial by combat until the Gulf War. While the F 117A was called the " stealth fighter" ， it was actually designed and used as a light bomber. The mission it was designed for was to penetrate18 thick Soviet air defenses in Central Europe and attack key targets and air defense systems （radars， command centers， and missile launchers）。 The Iraqi air-defense system was built with Soviet assistance and largely with Soviet equipment. The F-117A had little trouble dealing with it. Production of the initial batch19 of F-117As was completed in the late l980s.
Meanwhile， another " black" （secret） project， the B-2 bomber， was also built using stealth technology. The B-2 is an enormously expensive aircraft as it contains even more advanced stealth technology， carries much more weight in bombs， and has a much longer range. The cost of this program makes it difficult for the Air Force to justify building more than a handful of B-2s. The Air Force has other stealth projects that deal with reconnaissance20 work.
與海軍不同，美國空軍早在越戰(zhàn)期間就決心提高其轟炸精度。越戰(zhàn)結(jié)束前，空軍就研制并率先使用了制導(dǎo)炸彈系統(tǒng)。該系統(tǒng)用于攻擊定位精確的目標時的效果很好。這種目標先前難以用常規(guī)攻擊方式加以摧毀（空軍的許多轟炸機被密集的防空炮火所擊落）。在整個70年代和80年代，空軍一直在研制更好的轟炸系統(tǒng)。該項目耗資巨大?？哲娪糜谘芯颗c開發(fā)的經(jīng)費比其他軍種多。這樣做的高明之處直到海灣戰(zhàn)爭才顯露出來。當時，海軍的飛機由于沒有裝備這種系統(tǒng)，轟炸效果要差得多。
讓我們分析一下在過去50年里發(fā)生的3次戰(zhàn)爭，轟炸一個長100英尺寬60英尺的目標（通常是一幢可容納一個指揮所、一家工廠或其他單位的大樓），毀傷概率為90％，需要多少飛行架次和投擲多少炸彈：在40年代（二戰(zhàn)時期），需出動重型轟炸機（B-17）1500架次，投擲1噸重的炸彈9000枚（有一半炸彈偏離目標3300多英尺）；在60年代（越戰(zhàn)期間），由于使用更為精確的轟炸系統(tǒng)，摧毀同樣目標只需出動噴氣式戰(zhàn)斗轟炸機（F-4"鬼怪式"） 176架次，每架飛機攜帶1枚炸彈（其中一半炸彈偏離目標400多英尺）；在90年代（海灣戰(zhàn)爭期間），僅需一架輕型轟炸機（F-117A隱形飛機）出動 1個架次，該機只攜帶1枚1噸重的炸彈，炸彈將落在所瞄準目標的10英尺范圍之內(nèi)。
越戰(zhàn)中的一個慘痛教訓(xùn)是，空軍飛機攻擊敵嚴密防衛(wèi)的目標時傷亡慘重。要減少損失，可出動大批電子戰(zhàn)機和轟炸機摧毀敵人的雷達和防空武器。使用精確轟炸系統(tǒng)也可將損失減少到較能承受的程度?？哲姷睦碚撌牵l(fā)展那種使敵人雷達難以發(fā)現(xiàn)的飛機，是減少飛機和人員傷亡的更為有效的途徑。這樣，設(shè)計成幾乎讓敵方雷達看不到的"隱形"飛機，便可單機在有重要轟炸價值的目標區(qū)轟炸或摧毀敵防空體系。"隱形"飛機一旦裝有精確制導(dǎo)炸彈，空軍就擁有了一種實際上難以摧毀的轟炸機。這種飛機不僅能減少己方的傷亡，而且還能減少敵方平民的傷亡。第一種隱形飛機是F-117.為防止對手研制出對抗設(shè)施，F(xiàn)-117的生產(chǎn)十分保密。該飛機于80年代初開始投入使用，而首次真正接受作戰(zhàn)檢驗還是在海灣戰(zhàn)爭中。雖然F-117A被稱為"隱形戰(zhàn)斗機"，實際上它是被作為輕型轟炸機來設(shè)計和使用的。其任務(wù)是突入蘇聯(lián)在中歐的嚴密的防空體系，對重要目標和防空系統(tǒng)（雷達、指揮中心和導(dǎo)彈發(fā)射架）實施攻擊。伊拉克的防空系統(tǒng)是在蘇聯(lián)的幫助下建成的，所使用的裝備主要是由蘇聯(lián)提供的。F-117A型飛機對付它毫不費事。F-117A型飛機最初的批量生產(chǎn)完成于80年代末期。
與此同時，另一項采用隱形技術(shù)制造B-2轟炸機的"黑色"（秘密）計劃也已開始。B-2轟炸機由于使用了更先進的隱形技術(shù)，所以造價十分昂貴。該機的載彈量要大得多，航程也遠得多。昂貴的造價使空軍難以找出批量生產(chǎn)B-2轟炸機的充足理由?？哲娺€擬定了在偵察工作方面使用隱形技術(shù)的其他一些計劃。
注釋：
1.guided-bomb system 制導(dǎo)炸彈系統(tǒng)
2.pinpoint adj.[軍]定位精確的
3.shot down 擊落
4.dense adj.密集的，濃密的
5.budget n.預(yù)算拔款，?？?BR> 6.Gulf War 海灣戰(zhàn)爭
7.perspective n.視角，想法
8.probability n.[數(shù)]概率
9.heavy bomber 重型轟炸機
10.sortie vi.（軍用飛機）出動，出擊
11.phantom n.幽靈，[P-]鬼怪式飛機
12.stealth n.秘密行動[S-]隱形飛機
13.swarm n.蜂群，一大群
14.antiaircraft adj.防空的
15.tolerable adj.可容忍的
16.invulnerable adj.不會遭到攻擊的
17.countermeasure n.對策，反措施
18.penetrate vt.穿透，突破
19.batch n.一批生產(chǎn)量
20.reconnaissance n.偵察