540、If an engine fire detection system is available. describe, give principle of operation, and explain how to use it.

948、Most of the switches you use to control the electrical power system are on the electrical system controlpanel. 大多数用来控制电力系统的开关都在电力系统控制面板上。

947、 Mechanical power is produced by electric motors that are mainly used to drive pumps, for example, fuel and hydraulic pumps or to drive ‘a valve to the commanded position in the fuel, hydraulic or airconditioning system or to move mechanical parts like doors and cargo containers. 机械动力是由电机产生的，主要用于驱动泵，例如燃料泵和液压泵，或驱动阀门到燃料、液压或空调系统的命令位置，或移动机械部件，如门和货物集装箱。

946、Maximum landing gear operating speed is the maximum speed at which the landing gear can be safelyextended or retracted 最大起落架工作速度是起落架可以安全伸展或收放的最大速度

945、 Make sure that there is no dust on the surface

944、make sure that there is no blockage in the pipe 确保管道中没有堵塞

943、Make sure that the position of the clamp agrees with the position that you recorded during the removalprocedure. 确保夹具的位置与您在拆卸过程中记录的位置一致。

942、Make sure that the latch is fully engaged.

941、Make sure that the landing-light cutoff switch power connection is safe

940、Make sure that all the lights on the front of the CMU do not come on. 确保 CMU 前面的所有灯都不亮。

939、Make sure that all the galley compartments are empty