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Lesson OneText课文：The Classification of Aircraft 飞行器的分类Although all airplanes are aircraft, not all aircraft are airplanes. An aircraft is any structure 虽说所有的飞机都是飞行器，但不是所有的飞行器都是飞机。飞行器是指通过空气航that is Intended for navigation through the air and that is supported either by its own buoyancy or 行，由其自身的浮力或者依靠作用在其表面的空气动力支撑的一种结构。by the dynamic action of the air against its surfaces. A brief look at the various kinds of aircraft is 简单地看一看这些不同种类的航空器，就会对此感到一目了然in order, since you may fly a number of them during your aviation career and since FAA rules for 的，因为在你的航空生涯中你可能驾驶大量的航空器，而且联邦航空局关于飞行员或飞行员pilot or airmen certification are based on aircraft classification. The classification begins with 驾驶证的规定也是以航空器的分类为基础的。 分类从种类开始： categories: within a category, specific classes are identified : and within a class, types are 在一种种类中，分为详细的等级：而在一个等级中分为型号。identified.Category aircraft that use the same method of staying aloft and use similar means of propulsion 种类 利用同一种方法滞留空中和采用类似形式推进力的航空器被归为同一种类。are grouped into the same category. This is the broadest classification of aircraft. The FAA 这就是航空器最广义的分类。联邦航空局当前认为有四种currently recognizes the four categories of aircraft shown in Figure 1.1: lighter-than-air, 种类的航空器如图1.1所示： 轻于空气的（航空器）rotorcraft, glider and airplane. 旋翼式航空器，滑翔器和飞机。Class Within each category，aircraft with similar operating characteristics are grouped into a 等级 在每个种类中，具有类似操纵特性的航空器被分为一个等级，class ，For instance ，within the airplane category there are four classes: single-engine land, 例如，在飞机种类中有四个等级： 单引擎陆地（飞机）single-engine sea, multiengine land, and multiengine sea.单引擎海上（飞机），多引擎陆地（飞机）和多引擎海上（飞机）。Type When you refer to a specific make and model of aircraft，you are defining its type.型号 当你谈及一个明确的牌子和样式的航空器时，你指的是它的型号。 Here are some aircraft types you may be familiar with : Cessna 152，Piper Tomahawk，这里有你熟悉的几种航空器型号： ：BeechBonanza，Boeing 727，McDonnell Douglas DC-10. The Different Categories and Classes of AirCraft航空器的不同种类和等级Lighter-than-air aircraft ascend by displacing a free mass of heavier air with an enclosed mass 轻于空气的（航空器） 这种航空器通过用密封的轻型气体团替代自由的重空气团上升。of lighter gas. There are two classes of lighter-than-air aircraft：balloons and airships. Balloons are 有两种轻于空气的航空器：气球和飞艇。气球是驾驭空气气流飘行的无动力的unpowered aircraft that ride air currents. Hot-air balloons were common in the nineteenth century 航空器 热气球在19世纪是常见的而今天用于体育运动。and are used today for sport. Airships are powered and have controls to directs their movement. 飞艇有动力并且有操纵装置指引它们的运动。Inflatable/deflatable airships are called blimps. Dirigibles are airships built on rigid frames; 可充气/可放气飞艇被称作充气的飞艇。 飞船是刚性框架构成的飞艇。the famous German Zeppelins were dirigibles.著名的德国Zeppelines就是飞船。A rotorcraft is easily recognized by its large overhead propeller，called a rotor. There are two 旋翼式飞行器通过其巨大的顶部螺旋桨很容易辨认，称作旋翼。有两种的旋翼式飞行classes of rotorcraft：helicopters and gyroplanes. Helicopters have powered rotors that provide 器： 直升机和旋翼机。 直升机有动力旋翼，它通过空气提供垂直和水both vertical and horizontal motion through the air. On a gyroplane the rotor is freewhiling：平方向的运动的。 在旋翼机上，旋翼是行动自由的：propulsion is provided by an engine and propeller mounted in either a tractor (pulling) or pusher 推进力是通过一个引擎和固定在牵引机或推进器结构上的螺旋桨提供的。configuration. A glider is an unpowered aircraft with wings and a tail. A sailplane is a high-performance 滑翔机是一种带有机翼和一个尾部的无动力航空器。轻滑翔机是一种高性能滑翔机，能glider capable of remaining aloft on rising air currents. These aircraft can be towed aloft by an 够在上升气流中保持高空飞行。 这些航空器能被飞机或绞车拖拽到高处airplane or a winch，or they can be launched over the edge of a cliff. Once aloft，a glider or ，或者它们可以从悬崖上边抛投发射。 一旦处在高处，滑翔机或轻sailplane is always coasting down through the air immediately around it. A sailplane pilot stays 滑翔机总是立即沿着它周围的大气向下滑行。 轻滑翔机飞行员通过寻找aloft by finding rising air currents produced by the local terrain or weather conditions. 由当地地形或气候条件产生的上升气流来保持高空停留。An airplane is a powered aircraft with wings and a tail. The airplane category has four 飞机是一种带有机翼和尾部的有动力航空器。 飞机种类有四个等级：classes：single-engine land, single-engine sea, multiengine land, and multiengine sea. 单引擎陆地（飞机），单引擎海上（飞机），多引擎陆地（飞机）和多引擎海上（飞机）。Chapter 2 is devoted to describing airplane and how they fly.第2章致力于描述飞机和他们是如何飞行的。These descriptions of category，classes，and type are used by the FAA in defining pilot种类，等级，和型的这些描述被联邦航空局用在定义飞行员限制方面。limitations. Your pilot certificate will always specify each category and class of aircraft you may 你的飞行员证书将总是指明你能合法驾驶一种种类和级别的航空器。legally operate. When you move up to jet-powered aircraft or any aircraft that has a maximum 当你达到驾驶喷气动力的航空器或任何具有超过12，500磅最大起飞重量（大takeoff weight of over 12,500 pounds (about the size of a Lear jet or bigger) you will need a type 约是Lear jet 的尺寸或更大）的航空器时，你将需要你要飞的牌号和样式的型号等级rating in each make and model you fly. The term “category” is also used in another context：In the “类别“这个词也被应用于另一种情况：在航空器证书certification of aircraft , category refers to the operating limitations or intended use of the aircraft. 方面，“类别“指的是操纵限制或航空器的应用意图。The aircrafts Operating Handbook will discuss each category for which it is certified and the 航空器的操作手册将会讨论它所检定的每个种类和遵守的限制。limitations to be observed.There is one type of airborne vehicle that is not recognized by the FAA. An ultralight is a 这有一种没有被FAA认可的空运交通工具。 超轻型（飞行器）是lightweight，single-person，recreational aircraft like that shown in figure 1.2. The FAA defines 一种重量轻，单人乘，娱乐的航空器，就像图1.2所示。 FAA把他们定义为these as “vehicles” and does not regulate their design or construction. You do not need a pilots “交通工具”而没有管制它们的设计或结构。你不需要飞行员证书就可以进行驾驶飞行。certificate to fly one.You will need a pilots certificate to fly any kind of airplane ,and you will need training 飞行任何一种飞机你都需要飞行员许可证，而且在你获得许可证之前需要进行培训。before you obtain that certificate. Lesson TwoText课文The Parts of an Airplane飞机的部件Figure 2.1 shows the basic components of an airplane. Although each manufacturer and each 图 2.1 显示了一个飞机的基本部件。 虽然每个制造公司和每个式样都有model have their own design features，these general components are found on every airplane and 他们自己的设计特点，但这些通用部件在每架飞机上都能看到且具有相同的名字。called by the same names. The entire structure of an airplane is called the airframe. 飞机的整体结构称为机体。The components of the airframe are ：the wing ，the fuselage ，and the tail assembly ，飞机的部件是： 机翼， 飞机机身， 和 尾部组件or empennage. 或尾翼组。Wings are the major characteristic of an airplane. Wings can be mounted above the cabin 机翼是飞机的主要特征。 机翼可以安置在机舱的上部（上翼）(high wing)，below the cabin (low wing ) ，or anywhere between (mid wing ). Each manufacturer ，机舱的下部（下翼），或安置在机舱中部的任何位置（中翼）。 每个制造公司都有has its own preference. Most modern airplanes are monoplanes：that is ，they have one wing. 它们自己的偏爱。 大多数现代飞机都是单翼飞机：即它们有一副机翼。Airplanes with two wings are called biplanes. There have even been triplanes，the most famous of 有两幅机翼的飞机被称为双翼飞机。 甚至有三翼飞机，最著名就是一战中Red Baron 驾which was the Fokker triplanes flown by the Red Baron in World War I. 驶的Fokker三翼飞机。On the trailing (rearmost) edge of the wing are two sets of movable surfaces. Those farthest 在机翼的最后沿有两套可移动面。 距离飞机中心from the center of the airplane (outboard) are called ailerons. The ailerons move when you turn the 线最远的（外侧的）被称为副翼。 当你转动操纵盘或来回摆动操纵杆control wheel or move the control stick side to side. They move in opposite directions ,one going 时副翼就会移动。 它们在两个相反方向上运动，一个向上时up while the other goes down . Flaps are the movable surfaces closest to the center (inboard). 而另一个向下。 襟翼是靠近中心（内侧的）的可动面。They are controlled by a lever or switch in the cockpit . Flaps only move downward (sometimes 它们由驾驶座舱内的杠杆或开关控制。 襟翼仅仅向下移动（有时也如向下移动backward as well as downward)，and both flaps always move simultaneously. 一样而向后移动），并且两个襟翼总是同时运动。On most airplanes ,the wings contain the fuel tanks. This is both structurally efficient and 在大多数飞机上，机翼容载油箱。 这就是结构的高效性与实用性。practical. The weight of the fuel is distributed along the structure that is doing the lifting , and it 燃油的重量分布于能够产生升力的结构上，从而可使机体的其余部分装载旅客和货leaves the rest of the airframe available for other things , like people and cargo.物等其他货物。When you observe an airplane from the front or rear，you will notice that the wings are not 当你从飞机的前面或尾部观察飞机时，你将注意到机翼与地平面并不平行，而是形成一parallel to the ground but form a slight V (see Figure 2.2). This angle is called dihedral. The 个微小的“V”形角。 该角称为上反角/下反角。反角的目的purpose of dihedral will be discussed later in this chapter. 将在本章后面讨论。The fuselage is the body of the airplane. It holds the pilot，passengers，and cargo. The 机身是飞机的躯干部分。 它容纳飞行员，乘客，和货物。fuselage is designed to as small as possible for performance reasons yet spacious enough for 从飞行性能考虑，机身体积尽可能设计小一些，而从舒适角度也应考虑足够的宽敞型。comfort.The tail assembly or empennage consists of two sets of surfaces，usually one horizontal and 尾部集合或尾翼由两组面组成，通常是一组水平的和一组垂直的。one vertical . (There are airplanes that use a V configuration ，but these are not discussed here to （有一些应用“V”形结构的飞机，但为了减少混乱这些结构在此不加讨论。）reduce confusion . ) The vertical element has a fixed part called the vertical stabilizer and a 垂直部分有一个固定部件，称作垂直安定面，还有一个可移动部分，movable part called the rudder . The rudder is controlled by pedals on the cockpit floor. The 称作方向舵。 方向舵是由驾驶座舱地板上的踏板控制的。horizontal surface usually has a fixed horizontal stabilizer and a movable elevator . On some 水平部分通常有一个固定的水平安定面和一个可移动的升降舵。 在某些飞机上airplanes the entire horizontal surface moves，in which case it is called a stabilator . The elevator 整体水平部分可以移动，这种情况下它被称为全动平尾。 升降舵或全动or stabilator is controlled by the fore and aft movement of the control wheel or stick. 平尾由驾驶盘或驾驶杆的前后移动来控制。The engine and propeller on most single-engine airplanes are mounted on the front of the 大部分单发动机飞机上的发动机和螺旋桨被安放在机身前部。fuselage. This is called the tractor (pulling ) configuration . The protective skin around the engine 这被称为牵引布局。 围绕在发动机周围的保护蒙皮称为is called the cowl. It provides a smooth exterior surface and channels cooling air around the 外罩。 它提供光滑的外表面并且引导发动机周围的冷却空气。engine. The undercarriage of an airplane is its landing gear. Early airplanes had two main wheels 飞机的起落架是它的着地装置。 在早期飞机在机身或机翼下面有两个under the fuselage or wings and a smaller wheel under the tail. Since this was the original method 主轮，在尾部有一个较小的轮子。 因为这是原始的设计起落架方法，of designing landing gear , it is called conventional landing gear (see Figure 2.3). Today most 所以它被称为老式/传统起落架（看图2.3）。 今天绝大部分飞airplanes are designed with the main wheels farther aft on the fuselage or wing and with a nose 机设计，将主起落架位置设计在机身后部或机翼下，同时用机头的前轮代替了（过去的）wheel rather than a tail wheel. This is the tricycle configuration. Tricycle gear airplanes are easier 尾轮。 这就是前三点式起落架设计。 前三点式起落架飞机在地面上to control on the ground，Especially during landing.较容易控制，特别是在着陆时。The landing gear on an airplane is either fixed or retractable. Fixed gear is cheaper, easier to 飞机起落架有的是固定的，有的是可回收的。 固定的起落架便宜，容易维护，maintain, and foolproof (you dont have to remember to put it down before landing ). 和无比安全（在着陆前你不必不得不记得放下起落架）。Aerodynamically, a retractable gear is preferable because with the wheels and struts placed inside 就空气动力学而言，可回收起落架是较优越的，因为当把轮子和支柱放在机翼或机身里时the wing or fuselage , there is less interference with the flow of air.就减少了对空气流动的干扰。Lesson ThreeText课文Why Airplanes Fly (I)飞机为什么能飞The Forces of Flight飞行力An airplane in flight is at the center of a continuous tug-of- war between two pairs of 在飞行状态中，飞机位于两组对抗力（看图3.1）保持平衡的中心点，升力对重力，opposing forces (see Figure 3.1) . Lift opposes weight and thrust opposes drag .推力对阻力。 Gravity constantly pulls the airplane toward earth . We measure the effects of gravity by the 飞机受到恒定的重力，方向指向地面。 我们通过飞行器和它的货物的重量来测量weight of the aircraft and its cargo.重力的影响。Thrust is any force acting in the same direction as the airplane flight path (the motion of the 推力是任何与飞机飞行路径（飞机穿过大气的运动）方向相同的力。airplane through the air). Typically the power plant system (the engine and propeller) provides this 典型地，动力设备系统（发动机和螺旋桨）提供这个力。force .Lift and drag are the forces produced by the motion of the airplane through the air. As a pilot, 升力和阻力是飞机穿行大气运动产生的力。作为飞行员，为了合理地应用这些力，你you must understand how these forces are generated in order to use them properly. Lift acts 必须懂得它们是如何产生的。 升力垂直perpendicular (at a 90-degree angle) to both the flight path and the wings span (the wing-tip to 于（90度角）飞行方向和机翼的跨度方向（翼尖到翼尖的方向）。wing-tip direction). See Figure 3.2. Drag is any force acting parallel to the flight path but in the 看图3.2。 阻力是平行于飞行方向却与飞行方向相反的任何力。opposite direction. Whenever the airplane is flying at a constant airspeed along a steady flight path (a steady 每当飞机沿着不变航向等速飞行（平稳爬升，平稳下降，或平飞）时，它就是在静态条climb, a steady descent, or straight and level) it is in static flight conditions. In static flight the 件下。 在静态飞行中，作用opposing forces on the airplane are balanced：that is ，lift equals weight and thrust equals drag . 在飞机上的对抗力是平衡的：即，升力与重力平衡，推力与阻力平衡。Whenever an airplane is turning ，changing speed，or changing rate of climb or descent，the 每当飞机转向、变速、或改变爬升或下降速率时，对抗力不再平衡，opposing forces are not balanced. However , under any changing conditions the airplane is always 然而，在任何变化的条件下，飞机总是在力图均衡相互对抗attempting to equalize the opposing forces and return to static flight.的力，并恢复到静态飞行的状态。The Creation of Lift 升力的产生The actions of the physical forces that support an aircraft in flight are not visible. But rest 飞行中支撑航空器的物质力的作用姿态是不可见的。但是航空器运动时，这些力确保assured that these forces keep an airplane aloft while it moves. Two basic laws of physics, 它能停留空中。 物理学的两个基本定律，Newtons Third Law of Motion and Bernoullis Principle, help explain the phenomenon of flight. 牛顿第三运动定律和伯努利原理，帮助解释飞行现象。These principles are not difficult to understand when they are explained in practical, flight-related 当这些原理从实践的，相对飞行的角度解释时，它们是不难理解的。terms.Newtons Third Law of Motion states that for every action there is an equal and opposite 牛顿第三运动定律讲述每一个作用都有一个大小相等方向相反的反作用。reaction. If you could observe the airflow in front of and behind an airplane in flight ，you would 飞行中如果你观察飞机前后的气流，你将看到飞机后面的空气是向下的。see that the air behind the airplane is redirectedly downward. The downward force caused by the 由机翼引起的向下的力称为下冲气wing is called downwash. The action of redirecting the air down causes the reaction of lifting the 流。 转向下降气流的作用引起提升飞机的反作用。airplane. Only when the mass of air directed down by the wings equals the mass of the airplane 只有当机翼的下推的空气质量力与飞机运动的质量力均等时，飞机才能飞行。does the airplane fly. Air rushing around and down behind the wings makes an airplane fly. 在机翼后面来回冲撞的空气使飞机得以飞行。Airfoils Any structure that moves through the air for the purpose of obtaining a useful reaction 翼型 为了获得有用的反作用力在空气中运动的任何结构称为翼型。is called an airfoil . Although airfoils are found in a number of places on an airplane-the wing ， 虽说翼型在飞机上许多地方可以看到机翼，尾翼面，和螺旋桨但是机tail surfaces ，and propeller the wing is the most important . The special shape of the wing is the 翼是最重要的地方。 机翼特殊的形状是它成功的秘密。secret to its success. Figure 3.4 shows a cross-section of typical airfoil in motion through the air. 图3.4 显示了在空气中运动的典型翼型的横截面。The airfoil has a rounded leading edge and a sharp trailing edge. The curved shape of the upper 翼型具有圆形的前缘和尖形的后缘。 上下面的曲线形状称为曲度弧。and lower surface is called camber. The chord (or chord line ) is a hypothetical straight line that 弦（或弦线）是通过翼型前后缘的一条假象直线。passes through the leading and trailing edges of the airfoil. Relative Wind and Angle of Attack The stream of air approaching the airfoil is called relative 相对气流和迎角 靠近翼型的气流称为相对气流，因为它是运动的气团并wind since it is a moving mass of air and has a direction relative to the airfoil. The direction of the 且相对翼型有一方向。 相对气流方向与翼relative wind is exactly opposite that of the flight path of the airfoil. In fact ，relative wind is the 型飞行方向恰恰相反。 实际上，相对气流是飞行路result of the flight path. The angle that the relative wind makes with the chord line is called the 径的结果 相对气流与弦线的夹角称为迎角。angle of attack. When describing the magnitude of this angle ，the term low angle of attack means 当描述这个角大小时，低迎角这个术语意味着相对气流与弦线的夹角是小迎a small angle between the relative wind and the chord line. As the angle between the relative wind 角。 随着相对气流与弦线夹角的增加，迎and the chord line increases , the angle of attack gets higher. 角变高。Although these effects hold for every airfoil on the airplane ，the wing is the primary airfoil 尽管这些作用适用于飞机的每个翼型（气动力面），但是，机翼是任何飞行员应该注意of interest to you as a pilot . The wings relative wind is a result of the flight path of the entire 的主要翼型(气动力面)。 机翼的相对气流是整个飞机飞行路径的结果。airplane. Realizing this is an important step toward gaining a pilots un