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愿你经历再多，都不忘初心； 愿你难过再多，都不忘微笑； 愿你能披荆斩棘，做到自己想要做到的事 
Each engine has a full authority digital EEC. Each EEC has two independent control channels, with automatic channel transfer if the operating channel fails. With each engine start or start attempt, the EEC alternates between control channels. The EEC uses thrust lever inputs to automatically control forward and reverse thrust. N1 is used by the EEC to set thrust in two control modes: normal and alternate. Manual selection of the control mode can be made with the EEC switches on engine panel. 每一个发动机都有一个全数字化的电子发动机控制系统，每个EEC有两个独立的控制通道，这些通道之间在有故障时可以自动转换，在每一个发动机起动或者尝试起动时，EEC在控制通道之间互为备用。EEC使用推力杆输入自动控制正向和反向推力。E1使用N1在两种控制模式下设置推力：正常和备用方式，可以通过发动机面板上的EEC开关手动选择控制模式。一、EEC Normal Mode In the normal mode, the EEC uses sensed flight conditions and bleed air demand to calculate N1 thrust ratings. The EEC compares commanded N1 to actual N1 and adjusts fuel flow to achieve the commanded N1. The full rated takeoff thrust for the installed engine is available at a thrust lever position less than the forward stop. Fixed or assumed temperature derated takeoff thrust ratings are set at thrust lever positions less than full rated takeoff. The maximum rated thrust is available at the forward stop. The EEC limits the maximum thrust according to the airplane model as follows:· 737-700 – CFM56-7B24 rating· 737-800 – CFM56-7B27 rating EEC 正常方式 在正常方式下，EEC 用感应到的飞行状态和引气需求计算出N1 推力额定值。EEC 比较指令N1 和实际N1，并调整燃油量以获得指令的N1。推力手柄位置在未达到前止位时，所安装发动机的全额起飞推力可用。将固定或假设温度减功率起飞额定推力调定在小于全额起飞推力的推力手柄位置。在前止位可获得最大额定推力。EEC 如下所示根据飞机机型限制最大推力：· 737-700 – CFM56-7B24 额定推力· 737-800 – CFM56-7B27 额定推力二、EEC Alternate Mode The EEC can operate in either of two alternate modes, soft or hard. If required signals are not available to operate in the normal mode, the EEC automatically changes to the soft alternate mode. When this occurs, the ALTN switch illuminates and the ON indication remains visible. In the soft alternate mode, the EEC uses the last valid flight conditions to define engine parameters which allows the mode change to occur with no immediate change in engine thrust. Thrust rating shortfalls or exceedances may occur as flight conditions change. The soft alternate mode remains until the hard alternate mode is entered by either retarding the thrust lever to idle or manually selecting ALTN with the EEC switch on the aft overhead panel. EEC 备用方式 EEC 可在软或硬两个备用方式之一工作。如果在正常方式下无工作所需的信号，EEC 自动转换到软备用方式。出现此情况时备用电门亮，并且接通(ON)指示保持可见。在软备用方式下，EEC 使用最后有效的飞行条件定义发动机参数，这样发动机推力在没有立即的变化时就会出现方式的改变。当飞行条件改变时，可能出现推力不足或过大。软备用方式保持直至通过将推力手柄收到慢车位或者在后顶板上用EEC 电门人工选择备用方式进入硬备用方式为止。Note: Loss of either DEU results in a loss of signal to both EECs. The EEC ALTN lights illuminate and each EEC reverts to the alternate mode to prevent the engines from operating on a single source of data. When the hard alternate mode is entered, the EEC reverts to the alternate mode thrust schedule. Hard alternate mode thrust is always equal to or greater than normal mode thrust for the same lever position. If the hard alternate mode is entered by reducing the thrust lever to idle while in the soft alternate mode, the ALTN switch remains illuminated and the ON indication remains visible. When ALTN is selected manually, the ON indication is blanked. 注：任一个编码器/解码器(DEU)失效会导致两个EEC 无信号。EEC 备用灯亮且每个EEC 转换到备用方式以防止发动机以单独的数据源工作。进入硬备用方式后，EEC 转换到备用方式推力计划。在相同手柄位置，硬备用方式推力总是等于或大于正常方式推力。在软备用方式时，若通过减小推力至慢车进入硬备用方式，备用电门保持亮，并且ON 指示保持可见。当人工选择备用方式时，ON 指示空白。三、Structural Limit Protection The EEC provides N1 and N2 redline overspeed protection in both normal and alternate modes. The EGT limit must be observed by the crew because the EEC does not provide EGT redline exceedance protection. 结构限制保护 在正常和备用方式下，EEC 都提供 N1 和 N2 红线超速保护。因为 EEC 不提供排气温度红线超温保护，所以机组人员必须遵守排气温度极限。四、Idle Operation The EEC automatically selects ground minimum idle, flight minimum idle, and approach idle. Ground minimum idle is selected for ground operations and flight minimum idle is selected for most phases of flight. Approach idle is selected in flight if flaps are in landing configuration or engine anti–ice is ON for either engine. At the same airspeed and altitude, N1 and N2% RPM will be higher for approach idle than for flight minimum idle. This higher% RPM improves engine acceleration time in the event of a go–around. Approach idle is maintained until after touchdown, when ground minimum idle is selected. In flight, if a fault prevents the EEC from receiving flap or anti–ice signals, approach idle schedule begins below 15,000 feet MSL. 慢车操作 EEC 自动选择地面最小慢车、飞行最小慢车和进近慢车。选择地面最小慢车用于地面操纵，而在大部分飞行阶段选择飞行最小慢车。如果襟翼在着陆形态或任一台发动机防冰接通时，在飞行中选择进近慢车。在同样空速和高度上，进近慢车的 N1 和N2%RPM 会高于飞行最小慢车的 N1 和 N2%RPM。这一较高的 %RPM 缩短了复飞时发动机的加速时间。进近慢车保持直到接地后选择了地面最小慢车的时候。在空中，如果故障使 EEC 不能接收襟翼或防冰信号，在 15000 英尺 MSL 以下开始使用进近慢车计划。五、故障保留 
使用FPPM或FCOM手册中提供的数据表格修正 
1、对于CFM56-7B18,-7B20,-7B22 以及-7B24 推力额定值的发动机在EEC备用方式(ALTN EEC 电门亮)下工作时，不需要修正起飞速度或其他性能值。不允许减额定功率和/或假设温度减推力起飞。No takeoff speed adjustments or other performance adjustments are required of Electronic Engine Control (EEC) in alternate mode (ALTN & EEC switch illuminated) for the CFM56-7B18, -7B20, -7B22, -7B24 and -7B24A engine thrust ratings. Operation with derated and/or assumed temperature reduced takeoff thrust is not permitted with the EEC in the alternate mode. 2、对于CFM56-7B26K(或27K)推力额定值的发动机在EEC备用方式(ALTN EEC 电门亮)下工作时，需要根据相应软件或手册修正起飞速度、N1%和其他性能值。不允许使用减额定功率和/或假设温度减推力起飞。Takeoff speed adjustments or other performance adjustments are required of Electronic Engine Control (EEC) in alternate mode (ALTN & EEC switch illuminated) for engine thrust ratings at 26K and higher. Operation with derated and/or assumed temperature reduced takeoff thrust is not permitted with the EEC in the alternate mode. 性能分析案例-谢谢性能工程师
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