(5)
Press EXP pushbutton, and slew display until ENABLE RNAV is between entry line markers.
(6)
Press ENT pushbutton and observe the U UDT MODE: RNAV (or UDT: ENABLED) Page is in view. Observe the following:
(a)
The active update source (or sources) is displayed on line 2.
(b)
The frequency and station designator of the catalog station being tuned is displayed on line 4.
(c)
Update advisory messages (if present) are displayed on line 5.
(7)
Verify that the INS updating annunciators change from black to green.
IF -
NOT OK
NOT OK
OK
NOT OK
FREQUENCY OF CATALOG STATION DISPLAY ON CDU BUT NOT DIS-
PLAYED ON VHF NAVIGATION CONTROL PANEL - Replace in sequence:
(1)
VHF Nav control panel (Ref 34-31-01)
(2)
INU (Ref 34-41-03)
INS UPDATING ANNUNCIATORS NOT GREEN - Replace in sequence:
(1)
INS updating annunciator
(2)
INU (Ref 34-41-03)
EFFECTIVITY
CONFIG 3 AIRPLANES WITH LTN-72RL OR
799 Page 110 LTN-92 INS
Apr 25/91
34-41-00
EFFECTIVITY
CONFIG 3 AIRPLANES WITH LTN-72RL OR
799 Page 111 LTN-92 INS
Apr 25/91
34-41-00
PROCEDURE 1
LAT OR LON LINES CONTINUE TO FLASH. IF -
LAT LINE FLASHES CONTINUOUSLY AFTER LAT-LON LINE FLASHES CONTINUOUSLY AFTER ITUDE IS ENTERED - Press CLR pushbutton, LONGITUDE IS ENTERED - Press CLR push-verify airplane present position lati-button, verify airplane present position tude and re-enter latitude. IF -longitude and re-enter longitude. IF -
LAT LINE STILL FLASHES - Replace in LON LINE STILL FLASHES - Replace in sequence: sequence:
(1)
CDU (Ref 34-41-02) (1) CDU (Ref 34-41-02)
(2)
INU (Ref 34-41-03) (2) INU (Ref 34-41-03)
PROCEDURE 2
CDU DOES NOT INDICATE AN ACTIVE UPDATING SOURCE - Check CDU display for update advisory message and correct update mode as required. IF -
CDU STILL DOES NOT INDICATE AN ACTIVE UPDATING SOURCE - Trouble shoot DME interro-gator (Ref 34-55), or VHF navigation receiver (Ref 34-31). IF -
INU (Ref 34-41-03) CDU (Ref 34-41-02) (2) (1) CDU STILL DOES NOT INDICATE AN ACTIVE UPDATING SOURCE - Replace in sequence:
EFFECTIVITY
CONFIG 3 AIRPLANES WITH LTN-72RL OR
799 Page 113 LTN-92 INS
Apr 25/91
34-41-00
PROCEDURE 3
PROCEDURE 4
PROCEDURE 5
EFFECTIVITY
CONFIG 3 AIRPLANES WITH LTN-72RL OR
799 Page 115 LTN-92 INS
Apr 25/91
34-41-00
INERTIAL NAVIGATION SYSTEM - ADJUSTMENT/TEST
___________________________________________
1. Operational Test - Inertial Navigation System
_____________________________________________
A. General
(1) The INS operational test is similar to the preflight procedure used to prepare an INS for flight. This requires that exact aircraft present position and intended waypoint latitude and longitude be known. The procedure is identical for each individual INS undergoing test. This test requires no special tools.
B. Referenced Procedures
(1)
21-58-00, Equipment Cooling - Adjustment/Test (Operational Test)
(2)
24-22-00, Manual Control - Maintenance Practices (Apply Power)
C. Equipment and Materials
(1) Cards containing airplane present position and waypoint information.
D. Prepare for Test
(1)
Set mode selector switch on each mode selector unit (pilots' overhead panel P5) to OFF position.
(2)
Verify that STANDBY IGNITION switch on overhead panel P5 is in NORM position.
(3)
Provide electrical power (Ref 24-22-00).
(4)
Provide cooling air to INS equipment (Ref 21-58-00).
CAUTION: ENSURE THAT COOLING AIR IS AVAILABLE TO NAVIGATION UNITS
_______ BEFORE OPERATING INS. FAILURE TO PROVIDE ADEQUATE AIR SUPPLY WILL RESULT IN FAILURE OF NAVIGATION UNITS.
NOTE:____Main air supply is separate from INS fans. To verify INS fan operation, listen for sound of fans.
(5)
Close all INS, ADI and HSI circuit breakers on electronic circuit breaker panel P7. LH 011-030, 051-070, 081-099; AF 121, 122, 151-199; AZ 221-299; MD 501-599, GN 601-699; AT 701-750; VM 751-799; also close all INS, ADI and HSI circuit breakers on electronic circuit breaker panel P126.
(6)
On airplanes with PMS,
open PMS circuit breakers (Ref 34-62-00).
NOTE: When the PMS has waypoint control, the INS CDU's operate
____
as display units only.
E. Test Inertial Navigation System 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(18)
