2022 年 8 月 – 第 4 页

CFM56-7B发动机PS13传感器的松动凸起和缺失的处理

发动机中心对PS13问题的小结

关于货仓火警探测单环路失效MEL 26-19-01-01是否适用于单环路自发火警的情况

SR 3-5361695619

因执行O项时,单环路自发火警的表现与MEL中的不一致，就此和波音做了沟通。通过多轮的交流，波音表示放单环路，在未测试时就出现火警，是需要执行排故的。不能依据MEL保留放行。

1. HNA asks: “Whether MEL 26-19-01-01 is only applicable when there is inoperative loop in cargo compartment?”

R1) MEL 26-19-01-01 can be applied when one loop (A or B) in each cargo compartment (FWD or AFT) is inoperative, provided that the opposite loop is checked to operate normally.

2. HNA asks: “According Boeing’s response, for example, If this is the case (fire warning appears automatically when select switch is put to A and the Cargo Fire Panel TEST switch has not been pressed and held yet, but fire warning test is normal when select switch is put to B ), the plane can not be dispatched per MEL 26-19-01-01? It requires troubleshooting?”

R2) If the TEST switch has not been pressed yet (there is no test going on) and the fire warning appears, there is either a fire in one of the cargo compartments or there is an issue with the system which requires troubleshooting.

关于737NG MEL 34-13 DME保留的解释

2022年8月，近期运行中，出现DME保留的疑问：一部失效按MEL放行，维护注释1可以通过CDU里设置将DME UPDATE设置到OFF位，如果这样设置FMC将不使用两部DME位置更新，这样的话和维护注释3是不是冲突了？

经过与波音的沟通，波音表示：从CDU页面设置到OFF是“软失效”，FMC仍会尝试使用能正常工作的DME功能；拔跳开关的操作是“硬失效”，受影响的DME彻底不工作。无论用哪种方式，对于FMC而言只要有能用的DME（或其功能）就会继续接着用，所以注释3本身也没太大问题，更多可能是理解上的偏差，再就是该条注释目前的描述可能更针对于注释2这种“硬失效”状况，所以波音表示准备修改DDG以完善描述。