747飞机维护手册AMM CHAPTER 34 - NAVIGATION 第34章导航3(10)

曝光台 注意防骗 网曝天猫店富美金盛家居专营店坑蒙拐骗欺诈消费者

 NOTE: These action, malfunction codes usually occur on the next
____ turn-on after a failure in NAV Mode where the CDU display has blanked and the warn light has come on. It is very important to record these codes because if the fault should happen to be intermittent then the codes will be erased at turn off and will not be shown on subsequent turn-ons. These codes are very helpful for maintenance personnel. If investigation of the malfunction shows that the action code was a result of a procedural error (e.g., taxiing before READY NAV light has come on, it is not necessary to remove the INU). The action code (1) will be recalled at next turn-on. This code will disappear when the system is cycled OFF and ON one more time.
 G. Remote Data Loading Problems
 (1)  The trouble shooting tree is based on the operation of one INS and, therefore, does not include a check of the remote data loading and displaying functions. If the data does not load (or loads incorrectly) repeat loading process two or three times and/or use a different INS to do the loading. If each INS will accept the data at least once, no component change is necessary.
 EFFECTIVITY AIRPLANES WITH LTN-72 INS  
  CONFIG  01 A Page 103  Apr 25/86

34-41-00
 H.  Ground Crew Call Horn Sounding
 (1)  The INS will automatically transfer to battery power if the INS is not turned off before ground power is removed from the airplane. In order to protect the INS batteries from inadvertent discharge, a ground crew call horn, located in the nose wheel well, activates 30 (| 10) seconds after the INS transfers to battery power with the airplane sitting on the ground. The horn will also sound if the equipment cooling system detects no airflow. If either of these conditions occurs, the INS should be shut off immediately.
 3.  Action Code/Malfunction Code Display Procedure______________________________________________(See figure 101.)
 A.  When INS failures occur the INU generates action and malfunction codes that identify recommended action to correct the malfunction (Ref Fig. 101) and the reason(s) for the malfunction.
 B.  The action code is a one-digit numeral that is displayed on the CDU right numerical display, together with the status number, when the CDU display selector switch is set to DSR TK STS. The format and content of the right numerical display is shown in Fig. 101.
 C.  If an action code 1 thru 8 exists, the associated malfunction code can be displayed by pressing the HOLD pushbutton. The malfunction code (a two-digit numeral) is displayed on the CDU right numerical display, together with the status number (Ref Fig. 101).
 D.  More than one malfunction may exist. Repeated pressing of the HOLD pushbutton will cause a sequential display of code numbers for all malfunctions. Record each malfunction code displayed. The display will remain fixed until a subsequent pressing of the HOLD pushbutton. From 1 through 24 codes may be displayed if sufficient malfunctions exist, a different one appearing each time the HOLD pushbutton is pressed. When all codes have been cycled through the display, the next pressing of the HOLD pushbutton will cause the display to become 00 and the status number, and the next pressing will cause the display to become the action code and the status number.
 E.  Perform action for most severe malfunction recorded.
 F.  On airplanes with PMS,
 INS in PMS Waypoint Control Mode.

 (1)  
If a PMS transmission failure is detected by the INS, the INS issues malfunction code 34 and automatically reverts to INS waypoint control.

 (2)  
When the INS automatically reverts to INS waypoint control (refer to malfunction code 34) and the next TO waypoint is not stored in the INU, the INS issues malfunction code 35.

 (3)  
If the PMS failure is corrected, malfunction code 34 can be cleared from the INS CDU, and (if the ground speed is less than 75 knots) PMS waypoint control may be regained. If the ground speed is greater than 75 knots the PMS is locked out until the INS is down-moded to STBY.

 4.  Prepare for Trouble Shooting
____________________________
 A.  Set mode selector switch on each mode selector unit (pilots' overhead panel P5) to OFF position.
 EFFECTIVITY AIRPLANES WITH LTN-72 INS  
  CONFIG  01 A Page 104  Aug 25/87

34-41-00
 B.  Verify that STANDBY IGNITION switch on overhead panel P5 is in NORM position.
 C.  Provide electrical power (Ref 24-22-00, Maintenance Practices [Apply Power]).
 D.  Provide cooling air to INS equipment (Ref 21-58-00, Adjustment/Test [Operational Test]).
 CAUTION: ENSURE THAT COOLING AIR IS AVAILABLE TO NAVIGATION UNITS BEFORE
　
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：747飞机维护手册AMM CHAPTER 34 - NAVIGATION 第34章导航3(10)