901、If a supply shutoff valve was closed for less than five minutes ho maintenance is required and shutoffperiods are hot accumulative. 如果供应关闭阀关闭时间少于 5 分钟，则需要进行维护，关闭时间为热累积。

587、most secondary structures are important to the performance of the airplane

586、Most of the switches you use to control the electrical power system are on the electrical system control panel.

585、Mechanical power, is produced by electric motors that are mainly used to drive pumps, for example, fuel and hydraulicpumps or to drive a valve to the commanded position in the fuel, hydraulic or air conditioning system or to move mechanicalparts like doors and cargo containers.

584、Maximum landing gear operating speed is the maximum speed at which the landing gear can be safely extended orretracted

583、Make sure that there is no dust on the surface.

582、make sure that there is no blockage in the pipe

581 、 Make sure that the position of the clamp agrees with the position that you recorded during the removalprocedure.were3no

580、Make sure that the latch is fully engaged.

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

578、Make sure that all the lights on the front of) the CMU do not come on.