高等院校"十三五"重点规划 专业英语系列

(○) 选题策划 马佳佳 (9) 责任编辑 张忠远 李想 ()封面设计 刘长友

高等院校"十三五"重点规划 专业英语系列

《空管与签派专业英语阅读》是一本供航空航天类高等院校的大学生学习民航专业英语的教材，特别面向空中交通管制和签派专业的学生。本书的题材函盖了与民航业务相关的基本内容，不仅包含飞行史、飞机的结构、导航及机载设备、航空气象、飞行装载与配平、飞行程序设计等内容，也包含国家空域系统、机场协同决策、ADS - B 等一批最新的民航技术内容。本书的内容主要来源于近年来国外规章、杂志报道、学术期刊论文以及运行手册等。本书亦可作为民航系统各下属单位的飞行员、空乘人员、基地维修保养人员、行政管理人员学习和提高民航专业英语的教材和读物，以及广大民航爱好者学习民航英语的自学材料。

空管与签派专业英语阅读/沈志远主编.一哈尔滨：

哈尔滨工程大学出版社, 2019.6

I. ①空… II. ①沈… III. (1)空中交通管制 - 英语 阅读教学 —高等学校 - 教材(2)民用航空 - 机场 - 业务 - 英语 - 阅读教学 - 高等学校 - 教材 IV. (1)V355.1

(2)F560.81

中国版本图书馆 CIP 数据核字（2019）第054242号

KONGGUAN YU QIANPAIZHUANYE YINGYU YUEDU

As the most basic and important professional language in the civil aviation, English has always been one of the most important working technical for the subordinate units of civil aviation administration of China.

Air traffic control and dispatcher professional English reading is a textbook for college students in aviation and aerospace universities to learn professional English of civil aviation, especially for students majoring in air traffic control and airline dispatching. This book can also be used as a teaching material and reading material to learn and improve the professional English of civil aviation for various subordinate units of civil aviation system, such as pilots, flight attendants, maintenance staff and administrative staff, as well as a self-study material for civil aviation enthusiasts to learn civil aviation English.
《空中交通管制与调度员专业英语阅读》是一本针对航空航天大学大学生学习民航专业英语的教材，特别适用于空中交通管制与航空调度专业的学生。本书也可作为民航系统各下属单位，如飞行员、乘务员、维修人员、行政人员等学习和提高民航专业英语的教材和读物，也可作为民航爱好者学习民航英语的自学教材和读物。

This book covers the basic contents related to civil aviation. It includes not only flight history, aircraft structure, navigation and airborne equipment, aviation weather, flight loading and balancing, flight procedure design, but also a batch of the state-of-the-art civil aviation technologies and development directions such as national airspace system, airport collaborative decision-making are contained. The content and language of this book are novel, and the main information comes from the regulations, magazines and periodicals published abroad in recent years.
本书涵盖了与民航有关的基本内容。它不仅包括飞行历史、飞机结构、导航和机载设备、航空气象、飞行加载和平衡、飞行程序设计，还包括国家空域系统、机场协同决策等一批先进的民航技术和发展方向。本书内容和语言新颖，主要资料来源于近年来国外出版的法规、杂志、期刊。

There are 18 units in the book. Each unit consists of 4 part, like Reading Text, Words and Expressions, Exercises and Supplement Reading.

Shen Zhiyuan was responsible for the topic for each unit, reading text and words list selection, and the compilation of exercises. Zhou Siyao and Chang Yujin provide a supplementation and modification for the words list, exercises and exercises answers.
沈志远负责各单元专题、阅读课文和单词列表选编、练习题整理等工作。周思尧、常玉瑾对单词表、练习题和练习答案进行了补充和修改。

The compilation and publication of this book has been concerned and guided by the leaders of civil aviation college of Nanjing University of Aeronautics and Astronautics. I would like to thank Nanjing University of Aeronautics and Astronautics for its "13th five-year plan" professional construction program for providing this book with funding.
本书的编纂出版，得到了南京航空航天大学民航学院领导的关心和指导。感谢南京航空航天大学“十三五”专业建设项目为本书提供经费。

Considering to the limited level of the author, the any suggestions and improvement from the readers are welcomed.

Shen Zhiyuan

Nanjing, 2019

英语作为民航业最基础和最重要的工作语言，一直以来是中国民用航空局下属各单位高度重视的学习任务之一。

《空管与签派专业英语阅读》是一本供航空航天类高等院校的大学生学习民航专业英语的教材，特别面向空中交通管制和航空公司签派专业的学生。本书亦可作为民航系统各下属单位的飞行员、空乘人员、基地维修保养人员、行政管理人员学习和提高民航专业英语的教材和读物，以及广大民航爱好者学习民航英语的自学材料。

本书的题材涵盖了与民航业务相关的基本内容，不仅包含飞行史、飞机的结构、导航及机载设备、航空气象、飞行装载与配平、飞行程序设计等内容, 也包含对国家空域系统、机场协同决策等一批最新的民航技术和发展方向的介绍。本书的内容和语言新颖,主要资料来源于近年来国外出版的航空规章、期刊、论文等。

本书共 18 单元，每个单元课文由 Reading Text、Words and Expressions、Exercises 和 Supplement Reading 组成。

沈志远负责全书的构思、选材、生词表、练习的编写工作，周思遥和常雨劲对生词表、练习及答案做了补充和修改。

本书的编写和出版得到了南京航空航天大学民航学院有关领导的关心和指导,在此深表谢意。感谢南京航空航天大学"十三五"专业建设项目为本书出版提供的资助。

由于编者水平有限，书中欠妥和错误之处在所难免，敬请读者指正。
Unit 1 History of Aviation
I Reading Text
II Words and Expressions ..... 6
III Exercises
IV Supplement Reading ..... 10
Unit 2 Aircraft Structure ..... 17
I Reading Text ..... 17
II Words and Expressions ..... 20
III Exercises ..... 23
IV Supplement Reading ..... 24
Unit 3 Air Traffic Control ..... 42
I Reading Text ..... 42
II Words and Expressions ..... 46
III Exercises ..... 47
IV Supplement Reading ..... 48
Unit 4 Aircraft Weight and Balance ..... 54
I Reading Text ..... 54
II Words and Expressions ..... 58
III Exercises ..... 59
IV Supplement Reading ..... 60
Unit 5 Airport Delay ..... 66
I Reading Text ..... 66
II Words and Expressions ..... 70
III Exercises ..... 73
IV Supplement Reading ..... 74
Unit 6 Airport Collaborative Decision Making ..... 80
I Reading Text ..... 80
II Words and Expressions ..... 84
III Exercises ..... 87
IV Supplement Reading ..... 88
Unit 7 Airport Emergency Plans ..... 90
I Reading Text ..... 90
II Words and Expressions ..... 95
III Exercises ..... 96
IV Supplement Reading ..... 97
Unit 8 Navigation System ..... 101
I Reading Text ..... 101
II Words and Expressions ..... 105
III Exercises ..... 108
IV Supplement Reading ..... 109
Unit 9 Automated Dependent Surveillance-Broadcast ..... 112
I Reading Text ..... 112
II Words and Expressions ..... 117
III Exercises ..... 119
IV Supplement Reading ..... 120
Unit 10 National Airspace System ..... 124
I Reading Text ..... 124
II Words and Expressions ..... 129
III Exercises ..... 130
IV Supplement Reading ..... 131
Unit 11 Flight Plan ..... 136
I Reading Text ..... 136
II Words and Expressions ..... 144
III Exercises ..... 145
IV Supplement Reading ..... 146
Unit 12 Visual Flight Rule and Instrument Flight Rule ..... 149
I Reading Text ..... 149
II Words and Expressions ..... 155
III Exercises ..... 156
IV Supplement Reading ..... 156
Unit 13 Human Factors ..... 161
I Reading Text ..... 161
II Words and Expressions ..... 173
III Exercises ..... 176
IV Supplement Reading ..... 177
Unit 14 Risk Management ..... 183
I Reading Text ..... 183
II Words and Expressions ..... 188
III Exercises ..... 189
IV Supplement Reading ..... 190
Unit 15 Airline Pilots ..... 193
I Reading Text ..... 193
II Words and Expressions ..... 197
III Exercises ..... 198
IV Supplement Reading ..... 199
Unit 16 Meteorology ..... 203
I Reading Text ..... 203
II Words and Expressions ..... 206
III Exercises ..... 208
IV Supplement Reading ..... 209
Unit 17 Aircraft Fuel ..... 213
I Reading Text ..... 213
II Words and Expressions ..... 217
III Exercises ..... 218
IV Supplement Reading ..... 219
Unit 18 Future of Civil Aviation ..... 224
I Reading Text ..... 224
II Words and Expressions ..... 228
III Exercises ..... 228
IV Supplement Reading ..... 229
KEYS FOR EXERCISES ..... 232

The origin of mankind's desire to fly lost in the distant past. From the earliest legends there have been stories of men strapping birdlike wings, stiffened cloaks or other devices to themselves and attempting to fly, typically by jumping off a tower. The Greek legend of Daedalus and Icarus is one of the earliest known, others originated from India, China and the European Dark Ages. During this early period the issues of lift, stability and control were not understood, and most attempts ended in serious injury or death.
人类渴望飞翔的起源，在遥远的过去中消失了。从最早的传说开始，就有男人将鸟一样的翅膀、坚硬的斗篷或其他装置绑在自己身上并试图飞行的故事，通常是从塔上跳下来。希腊代达罗斯和伊卡洛斯的传说是已知最早的传说之一，其他传说起源于印度、中国和欧洲黑暗时代。在这个早期阶段，升力、稳定性和控制的问题没有得到理解，大多数尝试都以严重伤害或死亡告终。

The kite may have been the first form of man-made aircraft [Figure 1]. It was invented in China possibly as far back as the 5 th century BC by Mozi and Lu Ban. The later design often emulated flying insects, birds, and other beasts, both real and mythical. Kites spread from China around the world. After its introduction into India, the kite further evolved into the fighter kite, where an abrasive line is used to cut down other kites.
风筝可能是人造飞机的第一种形式[图1]。它在中国可能早在公元前 5 世纪就由墨子和鲁班发明。后来的设计经常模仿飞虫、鸟类和其他野兽，无论是真实的还是神话中的。风筝从中国传播到世界各地。风筝传入印度后，进一步演变为战斗机风筝，其中使用磨料线切割其他风筝。

From ancient times the Chinese have understood that hot air rises and have applied the principle to a type of small hot air balloon called sky lantern. A sky lantern consists of a paper balloon under or just inside which a small lamp is placed. Sky lanterns are traditionally launched for pleasure during festivals. Their military application is attributed to the general Zhuge Liang,
自古以来，中国人就明白热空气会上升，并将这一原理应用于一种称为天灯的小型热气球。天灯由一个纸气球组成，气球下方或内部放置一盏小灯。传统上，天灯是在节日期间发射的，供人们娱乐。他们的军事应用归功于诸葛亮将军，

who is said to have used them to scare the enemy troops.

Figure 1 Man-made aircraft

Eventually some investigators began to discover and define some basics of rational aircraft design. The most notable of these was Leonardo da Vinci, although his work remained unknown until 1797, and so had no influence on development over the next three hundred years. Leonardo studied bird flight, analyzing it and anticipating many principles of aerodynamics. He did at least understand that "An object offers as much resistance to the air as the air does to the object." Newton would not publish the Third law of motion until 1687.
最终，一些研究人员开始发现并定义理性飞机设计的一些基础知识。其中最著名的是列奥纳多·达·芬奇，尽管他的作品直到 1797 年才为人所知，因此在接下来的三百年里没有对发展产生任何影响。列奥纳多研究了鸟类的飞行，对其进行了分析，并预见了空气动力学的许多原理。他至少明白了“物体对空气的阻力与空气对物体的阻力一样大。牛顿直到 1687 年才发表第三运动定律。

Ballooning became a major "rage" in Europe in the late 18th century, providing the first detailed understanding for the relationship between the altitude and atmosphere. 1783 was a watershed year for ballooning and aviation, between June 4th and December 1 st several aviation firsts were achieved in France.
热气球在18世纪后期成为欧洲的一大“风潮”，为高度和大气之间的关系提供了第一个详细的理解。1783 年是热气球和航空的分水岭，在 6 月 4 日至 12 月 1 日之间，法国实现了几个航空第一。

Work on developing a steerable (or dirigible) balloon (now called an airship) continued sporadically throughout the 19 th century. The first powered, controlled, sustained lighter-than-air flight is believed to have taken place in 1852 when Henri Giffard flew 15 miles ( 24 km ) in France, with a steam engine driven craft.
在整个19世纪，开发可操纵（或可操纵）气球（现在称为飞艇）的工作零星地继续进行。据信，第一次动力、受控、持续的轻于空气的飞行发生在1852年，当时亨利·吉法德（Henri Giffard）在法国用蒸汽机驱动的飞行器飞行了15英里（24公里）。

Sir George Cayley was first called the "father of the aero plane" in 1846. During the last years of the previous century he had begun the first rigorous study of the physics of flight and would later design the first modern heavier-than-air craft [Figure 2]. Among his many achievements, the most important contributions to aeronautics include:
乔治·凯利爵士（Sir George Cayley）于1846年首次被称为“飞机之父”。在上个世纪的最后几年，他开始了对飞行物理学的第一次严格研究，后来设计了第一艘现代重于空气的飞行器[图2]。在他的众多成就中，对航空业最重要的贡献包括：

(1) Clarifying our ideas and laying down the principles of heavier-than-air flight.

(2) Reaching a scientific understanding of the principles of bird flight.

(3) Conducting scientific aerodynamic experiment and demonstrating drag and streamlining, movement of the center of pressure, and the increase in lift from curving the wing surface.

(4) Defining the modern aero plane configuration and comprising a fixed wing, fuselage and tail assembly.

(5) Demonstrations of manned, gliding flight.

(6) Setting out the principles of power-to-weight ratio in sustaining flight.

Figure 2 Sir George Cayley's Manuscript

The Wrights appear to be the first to make serious studied attempt to simultaneously solve the power and control problems. Using a methodological approach and concentrating on the controllability of the aircraft, the Wrights brothers had built and tested a series of kite and glider design from 1900 to 1902 before they attempted to build a powered design.
莱特兄弟似乎是第一个认真研究尝试同时解决电力和控制问题的人。莱特兄弟使用方法论方法并专注于飞机的可控性，从1900年到1902年，在他们试图构建动力设计之前，已经建造并测试了一系列风筝和滑翔机设计。

According to the Smithsonian Institution and Fédération Aéronautique Internationale (FAI), the Wrights made the first sustained, controlled, powered heavier-than-air manned flight at Kill Devil Hills, North Carolina, four miles ( 8 km ) south of Kitty Hawk, North Carolina on December 17 , 1903. The first flight by Orville Wright, of 120 feet ( 37 m ) in 12 seconds, was recorded in a famous photograph[Figure 3].
根据史密森学会和国际航空联合会 （FAI） 的说法，莱特兄弟于 1903 年 12 月 17 日在北卡罗来纳州基蒂霍克以南 4 英里（8 公里）的北卡罗来纳州杀魔山进行了首次持续、受控、动力重于空气的载人飞行。奥维尔·赖特（Orville Wright）在12秒内首次飞行120英尺（37米），被记录在一张著名的照片中[图3]。

Figure 3 First flight

It had seen great advancement in aircraft technology between World War I and World War II . Airplanes evolved from low-powered biplanes made from wood and fabric to sleek, highpowered monoplanes made of aluminum, primarily based on the founding work of Hugo Junkers during the World War I period and its adoption by American designer William Bushnell Stout and Soviet designer Andrei Tupolev. The age of the great rigid airships came and went. The first successful rotorcraft appeared in the form of the autogyro, invented by Spanish engineer Juan de la Cierva and first flown in 1919. In this design, the rotor is not powered but is spun like a windmill by its passage through the air. A separate powerplant is used to propel the aircraft forwards.
在第一次世界大战和第二次世界大战之间，它见证了飞机技术的巨大进步。飞机从由木材和织物制成的低功率双翼飞机演变为由铝制成的时尚、高功率单翼飞机，主要基于雨果·容克斯在第一次世界大战期间的创立工作，并由美国设计师威廉·布什内尔·斯托特和苏联设计师安德烈·图波列夫采用。伟大的刚性飞艇的时代来了又走了。第一架成功的旋翼机以旋翼机的形式出现，由西班牙工程师胡安·德拉西尔瓦（Juan de la Cierva）发明，并于1919年首次飞行。在这种设计中，转子没有动力，而是通过在空气中通过而像风车一样旋转。一个单独的动力装置用于推动飞机前进。

World War II achieved a great increase in the pace of development and production, of not only aircraft but also the associated flight-based weapon delivery systems. Air combat tactics and doctrines took advantage. Large-scale strategic bombing campaigns were launched, fighter escorts introduced and the more flexible aircraft and weapons allowed precise attacks on small targets with dive bombers, fighter-bombers, and ground-attack aircraft. New technologies like radar also allowed more coordinated and controlled deployment of air defense.
第二次世界大战在开发和生产方面取得了巨大的进步，不仅飞机，而且相关的基于飞行的武器运载系统。空战战术和学说占了便宜。发动了大规模的战略轰炸行动，引入了战斗机护航，更灵活的飞机和武器允许用俯冲轰炸机、战斗轰炸机和对地攻击机对小型目标进行精确攻击。雷达等新技术还使防空部署更加协调和可控。

The first jet aircraft to fly was the Heinkel He 178 (Germany), flown by Erich Warsitz in 1939 , followed by the world's first operational jet aircraft, the Me 262, in July 1942 and world's first jet-powered bomber, the Arado Ar 234, in June 1943.

After World War II， commercial aviation grew rapidly， using mostly ex-military aircraft to transport people and cargo. This growth was accelerated by the glut of heavy and super-heavy bomber airframes like the B - 29 and Lancaster that could be converted into commercial aircraft.
第二次世界大战后，商业航空发展迅速，主要使用前军用飞机来运输人员和货物。重型和超重型轰炸机机身（如B-29和兰开斯特）的过剩加速了这种增长，这些飞机可以转换为商用飞机。

USSR's Aeroflot became the first airline in the world to operate sustained regular jet services on September 15, 1956 with the Tupolev Tu - 104. The Boeing 707 and DC - 8 which established new level of comfort, safety and passenger expectation, ushered in the age of mass commercial air travel, dubbed the Jet Age.
1956 年 9 月 15 日，苏联的俄罗斯航空公司成为世界上第一家运营持续定期喷气式飞机服务的航空公司，拥有图波列夫 Tu-104。波音 707 和 DC-8 将舒适性、安全性和乘客期望提升到了新的水平，开创了大规模商业航空旅行的时代，被称为喷气式飞机时代。

The 1945 invention of nuclear bomb briefly increased the strategic importance of military aircraft in the Cold War between East and West. Even a moderate fleet of long-range bomber could deliver a deadly blow to the enemy, so great efforts were made to develop the countermeasure. At first, the supersonic interceptor aircraft were produced in considerable numbers. By 1955 most development efforts were shifted to guided surface-to-air missiles.
1945年核弹的发明短暂地增加了军用飞机在东西方冷战中的战略重要性。即使是一支中等规模的远程轰炸机舰队也可以对敌人造成致命的打击，因此在制定对策方面付出了巨大的努力。起初，超音速拦截机的产量相当可观。到1955年，大多数开发工作都转向了制导地对空导弹。

In 1979 the Gossamer Albatross became the first person to power aircraft to cross the English Channel. This achievement finally realized the dream of human flight for centuries.

In 1986 Dick Rutan and Jeana Yeager flew an aircraft, the Rutan Voyager, around the world unrefueled, and without landing. In 1999 Bertrand Piccard became the first person to circle the earth in a balloon.

In the beginning of the 21 st century, digital technology allowed subsonic military aviation to begin eliminating the pilot in favor of remotely operated or completely autonomous unmanned aerial vehicles ( UAVs ). In April 2001 the unmanned aircraft Global Hawk flew from Edwards AFB in the US to Australia non-stop and unrefueled. This was the longest point-to-point flight ever undertaken by an unmanned aircraft and took 23 hours and 23 minutes.
在21世纪初，数字技术使亚音速军用航空开始取消飞行员，转而采用远程操作或完全自主的无人机（UAV）。2001年4月，无人驾驶飞机“全球鹰”号从美国爱德华兹空军基地直飞澳大利亚，没有加油。这是无人驾驶飞机有史以来最长的点对点飞行，耗时23小时23分钟。

dirigible

sporadical

sustain

rigorous

aeronautics

clarify

drag

streamline

curving

comprise

fuselage

glide

methodological

monoplane

biplane

fabric

sleek

aluminum

autogyro

rotor

powerplant adj. 可驾驶的

. 飞船

adj. 零星的

. 维持; 支撑, 承担; 忍受; 证实

adj. 严格的,严厉的;严密的;严酷的

. 航空学；飞行术

. 澄清；阐明

vi. 得到澄清;变得明晰;得到净化

vt. 拖累; 拖拉；缓慢而吃力地行进

vi. 拖曳; 缓慢而吃力地行进; 阻力; 阻力累

. 流线型化

adj. 弯曲的

. 弯曲;曲线;变形

. 使弯曲;弯成弧形

。包含；由……组成

n. 机身（飞机）

. 滑翔;滑行

. 使滑行; 使滑动

n. 滑羏;滑行；滑移

adj. 方法的, 方法论的

n. 单翼机

. 复翼飞机，双翼飞机

. 组织；构造；建筑物

. 圆滑的;井然有序的

. 使……光滑;掩盖

. 打扮整洁;滑动

n. 铝

n. 旋翼机

n. 转子; 水平旋翼;旋转体

n. 动力装置

spun adj. 纺成的
    v. 纺;旋转(spin 的过去分词)
propel vt.推进;驱使;激励;驱策
doctrine n. 主义;学说;信条
coordinated adj. 协调的
vt. 调整;使调和;调节;整理(coordinate 的过去分词)
jet-powered adj. 喷气动力的
cargo n. 货物;船货;航空运输
glut vt. 使\cdots...充满;使\cdots...吃饱;过多供应
n. 供过于求;大量
usher n. 引座员,带位员;接待员;门房
vt. 引导,招待;迎接;开辟
vi.作招待员;当引座员
dubbed vt. 刺;授予...称号;结账(dub 的过去分词)
adj. 被称为的
moderate adj. 稳健的,温和的;适度的,中等的;有节制的
vi.变缓和,变弱
vt. 节制;减轻
countermeasure n. 对策; 反措施; 反抗手段
supersonic adj.超音速的;超声波的
n. 超音速;超声波
interceptor n. 拦截机;妨碍者
autonomous adj.自治的;自主的;自发的
jump off 跳下来;开始,开始进攻
end in 以....为结果;以.....告终
be attributed to 归因于......
low-powered adj. 低功率的

(1) 固定翼飞机

(2) 地空导弹

(3) 无人机

(4) 点对点飞行

(5) 喷气时代

(6) 推重比

(7) 军事用途

(8) 比空气重的飞行

(9) 远距离轰炸机

(10) 运动第三定律

(1) Ballooning became a major "rage" in Europe in the late 18th century, providing the first detailed understanding of the relationship between the altitude and atmosphere.

(2) Conducting scientific aerodynamic experiment and demons and streamlining, movement of the center of pressure, and the increase in lift from curving the wing surface.

(3) Airplanes evolved from low-powered biplanes made from wood and fabric to sleek, highpowered monoplanes made of aluminum, primarily based on the founding work of Hugo Junkers during the World War I period and its adoption by American designer William Bushnell Stout and Soviet designer Andrei Tupolev.
（3）飞机从由木头和织物制成的低功率双翼飞机演变为由铝制成的光滑、高功率的单翼飞机，主要基于雨果·容克斯在第一次世界大战期间的创立工作，并由美国设计师威廉·布什内尔·斯托特和苏联设计师安德烈·图波列夫采用。

(4) Even a moderate fleet of long-range bomber could deliver a deadly blow to the enemy, so great efforts were made to develop the countermeasure.

(5) Defining the modern aero plane configurati and comprising a fixed wing, fuselage and tail assembly.

It looks like an upside-down bathtub with wings, pretty odd for a spy jet that was among the nation's most highly classified pieces of military hardware.

As I stand in front of the plane code-named Tacit Blue at the National Museum of the U. S. Air Force, near Dayton, Ohio, I'm reminded that it still holds a bit of mystery.

Engineers made fun of Tacit Blue's design by nicknaming it the Whale, but the programdeclassified in 1996-was deadly serious. It was all about stealth. Pentagon Cold War strategists desperately wanted to build planes that could evade Soviet radar.
工程师们取笑Tacit Blue的设计，将其昵称为“鲸鱼”，但该程序在1996年解密 - 非常严重。这一切都与隐身有关。五角大楼的冷战战略家们迫切希望制造能够躲避苏联雷达的飞机。

And so the Air Force launched a "black program" to develop Tacit Blue and tested it at a secret government airbase in Nevada called " Area 51," according to CIA documents released in 2013 .

The program, which lasted from 1978 to 1985, aimed to develop a single-seater jet for battlefield surveillance.

Before last year's document release, the government had never acknowledged the existence of Area 51. For decades, a fenced-off area surrounding Nevada's Groom Lake was rumored to be a testing ground for some of the nation's most secret technology.
在去年的文件发布之前，政府从未承认过51区的存在。几十年来，有传言称内华达州格鲁姆湖（Groom Lake）周围的一个围栏区域是美国一些最秘密技术的试验场。

Two retired Air Force test pilots who flew Tacit Blue in the early 1980s, Ken Dyson and Russ Easter, spoke about why this plane was important and what sets it apart.

Although the plane flew 135 times and was never put into production, without Tacit Blue, there would have been no B - 2 Spirit bomber. The plane proved that aircraft with curved surfaces