(c)
Momentarily press both CDU TEST switches. While switches are depressed check that: 1) HOLD, REMOTE, INSERT and WY PT CHG keys plus ALERT, BAT and
WARN annunciators illuminate on both CDU's. 2) BAT and READY NAV annunciators on both MSU's illuminate. 3) All three data display indicators on both CDU's are
showing all eights.
(2) Turn on check and lamp test (AIRPLANES WITH LITTON LTN-72 INS)
(a)
Set AUTO/MAN/RMT switch on CDU's No. 1 and 3 to MAN.
(b)
Set mode selector switches on MSU's No. 1 and 3 to STBY.
(c)
On IB 406-409, place the CDU No. 1 and 3 data selector to POS, check that: 1) Red, amber and green lamps do not illuminate. 2) Left-hand data display is all zeros and an N. 3) FROM/TO display is 0 0. 4) Program number 72 28 is displayed in the right-hand data
display and the INSERT pushbutton illuminates. For the complete program number 0 is displayed in the right-hand display when the HOLD pushbutton is pressed.
(d)
On IB 410-499, place the CDU No. 1 and 3 data selector to POS, check that: 1) Red, amber and green lamps do not illuminate. 2) FROM/TO display is 0 0. 3) INSERT pushbutton illuminates. 4) Program number 72-50-01 is displayed as 72 in left display
and 50 01 in right display.
(e)
Set both CDU WPT switch to any position except 0.
(f)
Set both CDU data selector switches to TEST. Check that: 1) ALERT, BATT, and WARN lamps on both CDU's illuminate. 2) Left and right numerical displays are degree signs,
decimal points, arc-minute signs NS, EW, and all eights, except left digit of right numerical display is R. 3) From/To display is all eights.
(3) Turn on check and display test (AIRPLANES WITH LITTON LTN-72RL or LTN-92 INS).
(a)
Place mode selector switch on each MSU to STBY.
(b)
Press BRT and DIM pushbuttons on each CDU and verify that display brightens and dims.
(c)
Press STS pushbutton on each CDU, SYS STS/TEST page will appear on each CDU display with ALIGN between entry line markers.
(d)
Slew each CDU display up until SYSTEM TEST page appears (on each display) with DISPLAY TEST between entry line markers. Press EXP on each CDU and verify that: 1) Display pattern rotates through each of the five lines,
on each CDU display. 2) On each CDU, the WRN, BAT, ALR, and OFS annunciators come on. 3) The ALERT annunciator (on each HSI) comes on.
EFFECTIVITY
ALL 15 Page 502 Apr 25/9134-41-11
4) The INS updating annunciators (on pilots' main instrument panels) displays green.
(e)
On each MSU, press ALIGN (or READY NAV) and BATT annunciators. Verify that ALIGN (or READY NAV) annunciator comes on and BATT annunicator comes on.
(f)
To end test; press STS or EXP pushbutton on each CDU.
(4) Energize 28-volt dc battery bus and activate standby dc power (Ref 24-33-00).
NOTE: Perform steps (5) thru (8) as rapidly as possible to
____ prevent excessive power drain from INS battery units and possible overheating of navigation units.
(5)
Open both sets of 115-volt ac power circuit breakers on panel P7 (or P126) (PWR-INS 1 for system 1, PWR-INS 3 for system 3). Check that BAT annunciators illuminate on CDU's for INS 1 and INS 3.
(6)
Set INS BAT PARALLEL switch on flight engineer's panel P4 to ON position. Check that BAT annunciator on INS 3 CDU extinguishes and BAT annunciator on INS 1 CDU remains illuminated.
(7)
Open circuit breaker on front panel of INS 1 battery unit. Check that BAT annunciator on INS 1 CDU remains illuminated.
(8)
Open circuit breaker on front panel of INS 3 battery unit. Check that BAT annunciator on INS 1 CDU extinguishes.
D. Return airplane to normal.
(1) Set each INS mode selector switch to OFF position.
CAUTION: FAILURE TO MOVE MODE SELECTOR TO OFF WILL CAUSE INS TO
_______ AUTOMATICALLY SWITCH TO BATTERY POWER AND A WARNING HORN IN NOSE WHEEL WELL TO ACTUATE 30 (| 10) SECONDS AFTER POWER IS REMOVED FROM AIRPLANE.
(2)
Set STANDBY POWER switch to OFF.
(3)
Close both sets of 115-volt ac power circuit breakers (PWR-INS 1 for system 1 and PWR-INS 3 for system 3).
中國航空網 m.k6050.com
航空翻譯 www.aviation.cn
本文鏈接地址：747飛機維護手冊AMM CHAPTER 34 - NAVIGATION 第34章導航3(75)
