(a)  
Top line displays PGM 92-04-10.

 (b)  
CUSTOM DBASE is displayed between entry line markers.

 (c)  
The fourth line displays the airline code and data base expiration date: SNXXXX.

 (d)  
The fifth line displays CLR: CONTINUE

 (e)  
The ALIGN annunciator on MSU illuminates amber in color.

 (6)  
On airplanes with LTN-72RL INS, place mode selector switch on each MSU to STBY. Verify the following on each CDU display:

 (a)  
Title of data base (geographical zones for example USA & CANADA, or MEDITERRANEAN) is on top line.

 (b)  
Program 72-73-00 is on second line.

 (c)  
Prompt/display line between the entry line markers contains dashes for entry of present day, month, and year.

 (d)  
Enter todays date by pressing CDU pushbuttons corresponding to digits for day, month and year, in that sequence.

 (e)  
Press ENT pushbutton on the CDU. Verify that CDU display changes to show DATA BASE VALID between entry line markers.

 B.  Present Position Entry
 (1)  Airplane present position must be entered into the INS before platform alignment can begin. In the following example, the present position of the airplane is at the LAX ramp at latitude north 33.56.1 minutes and longitude west 118.24.3 minutes. Enter present position as follows:
 (a)  Verify that MSU mode switch is set to STBY.
 EFFECTIVITY

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34-41-00
 (2)  
Press POS pushbutton on CDU. Verify that POSITION (OR POSITION DATA) page with LAT and LON prompt/display lines appears on display with LAT line between entry line markers.

 (3)  
Press CDU 2N or 8S pushbutton to start latitude entry; N or S character replaces <> symbol in LAT prompt/display line and letter N appears following the POSITION (OR POSITION DATA) title line. Letter N remains while data is being entered and goes out when ENT is pressed.

 NOTE: The letter N following the title line in the display after
____ the initial pushbutton is pressed indicates that the display is prepared to accept a numerical rather than an alpha entry.
 (4)  Press CDU pushbuttons corresponding to latitude including any leading or trailing zeros.
 NOTE: If an invalid latitude is entered, LAT line will flash on and
____ off. Press CLR pushbutton and repeat steps (3) thru (5).
 (5)  
If latitude displayed is correct, press ENT pushbutton on CDU. Verify that LAT line flashes and display slews up to place LON prompt/display line between entry line markers.

 (6)  
Press CDU W4 or 6E pushbutton to start longitude entry; W or E character replaces <> symbol in LON prompt/display line and letter N appears following title line.

 (7)  
Press CDU pushbuttons corresponding to longitude, including any leading or trailing zeros.

 NOTE: If an invalid longitude is entered, LON line will flash on
____ and off. Press CLR pushbutton and repeat steps (7) and (8).
 (8)  If longitude displayed is correct, press CDU ENT pushbutton. Verify that LON line flashes and GMT prompt/display line appears on display.
 C. Greenwich Mean Time Entry
 (1)  
Greenwich Mean Time (GMT) is set to zero and starts counting when the INS is turned on. GMT data entry is used only for operator convenience and is not required for navigation. When actual GMT is entered, it is displayed when POS is pressed, and estimated time of arrival at waypoints in GMT may be displayed by pressing FPL and EXP. In the following example procedure, GMT is 12:45:10. Enter GMT as follows:

 (2)  
Press POS pushbutton on CDU. Verify that POSITION (or POSITION DATA) page appears on display.

 (a)  Slew GMT prompt/display line into position between entry line markers.
 EFFECTIVITY

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 (b)  Press the first pushbutton for GMT hours, including leading zero if applicable; in this example press 1. A 1 appears as first digit of GMT prompt/display line and the letter N appears following the title line.
 NOTE: The INS will not accept a first-digit GMT entry other
____
 than 0,1, or 2.

 (c)  
Press pushbuttons for remaining digits of GMT, in this example, press 2, 4, 5, 1, and 0.

 (d)  
If GMT displayed is correct, press ENT at the instant the preset time matches the actual GMT. The GMT blinks once to acknowledge entry. If value is incorrect, press CLR; repeat steps (c) and (d).
　
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