单选题 Systems consisting of several components, such as ice protection systems, may have Supplements for each component, such as propeller boots, wing and empennage boots, or heated airspeed static source, if the equipment is FAA Approved by component and marketed individually.

单选题 Many altimeters contain linkages that rotate a numerical counter in addition to moving pointers around the dial. A quick reference window allows the pilot to simply read the numerical altitude in feet. The motion of the rotating digits or drum-type counter during rapid climb or descent makes it difficult or impossible to read the numbers. Reference can then be directed to the classic clock-style indication. 许多高度表都包含了连接机构，它们不仅可以使指针在游标上移动，还可以旋转数字计算器。快速参考窗口使飞行员可以简单地读取以英尺为单位的数字高度。在快速爬升或下降时旋转数字或滚筒式计算器的运动使数字难以阅读或无法阅读。此时可以用经典的时钟式表做基准。

单选题 Functional Test: That procedure required to ascertain that a system or unit is functioning in all aspects in accordance with minimum acceptable system or unit design specifications . These tests may require supplemental ground support equipment and should be more specific and detailed than an operational test. It should contain all necessary information to perform proficiency test to maintain system or unit reliability at an acceptable level ,without reference to additional documents. “功能测试：该过程旨在确定系统或组件按照最低可接受设计标准在所有方面的功能。这些测试可能需要补充地面支持设备，并且应该比飞行测试更具体和详细。它应该包含所有熟练检查所必要的信息，以维持系统或组件在可接受水平上的可靠性，无需参考其他文件。

单选题 A turn coordinator senses and indicates the rate of both roll and yaw. The rotor of the gyro in a turn coordinator is canted upwards 30°. As such, it responds not only to movement about the vertical axis, but also to roll movements about the longitudinal axis. 转弯协调器感知并指示横滚和偏航的速度。转弯协调器中陀螺的转子向上倾斜30°。此时，它不仅响应纵轴上的运动，而且响应立轴上的滚动运动。

单选题 Wires and wire bundles must be supported by clamps or plastic cable straps. Clamps and other primary support devices must be constructed of materials that are compatible with their installation and environment, in terms of temperature, exposure to ultraviolet (UV) light, and wire bundle mechanical loads. They should be spaced at intervals not exceeding 24 inches. Clamps on wire bundles should be selected so that they have a snug fit without pinching wires.

单选题 The drain and vent system consists of lines collecting and carrying waste fluids and vapor overboard from the engine and nacelle accessories. Drains are provided to carry fluids from any point where lines and accessories may leak and where fluids may accumulate in a cavity. Fluid from forward and aft sumps, oil-fuel heat exchanger, VBV, and VSV are discharged overboard through drains. In addition, some drain lines serve as vents to carry air and vapor from the engine and accessory cavities.

单选题 Dissimilar metal corrosion refers to the corrosion that occurs when two or more different metals are in contact with each other in the presence of an electrolyte . In this situation, an electrochemical reaction is set up between the metals, which causes one of the metals to corrode more quickly than it would have done on its own. 异种金属腐蚀是指当两种或以上的不同金属在电解质下相互接触时发生的腐蚀现象。在这种情况下，金属之间会形成电化学反应，导致其中一种金属比其自身单独存在时更快地被腐蚀。

单选题 Distribution of air conditioning system is used to induct and distribute air.

单选题 There are three types of placards and markings.