TM 55-1510-222-10 Observe  INSERT/ADVANCE  pushbutton  annunciator illuminates. 19.  To load channel number Press keys in sequence. Example:    109  =  109.    Numbers  appear  in  left  data display as keys are pressed. 20.        INSERT/ADVANCE    pushbutton    - Press. Observe pushbutton annunciator extinguishes. NOTE · Any  number  will  be  accepted  by the   INS;   however   only   stations with  a  channel  number  within  the range   of   1   through   126   will   be used for TACAN mixing. · The channel number has an implied X suffix. · Decimal points and degree symbols   should   be   disregarded when reading altitude and channel number displays. 21.        INSERT/ADVANCE    pushbutton    - Press. Observe station latitude and longitude reappear. 22.    Repeat  steps  3  through  19  for  each TACAN station. 23.      To   return   INS   to   normal   display modes, momentarily set data selector to L/L POS. (7) Designating fly-to destinations: 1.  Data selector L/L WY PT or UTM WY PT, as required. 2.        Waypoint    thumbwheel    Select    destination number. Observe  number  of  destination  way-point  appears  in TO part of TO-FROM display. 3.  Data selector - HDG/DA. Observe present aircraft heading appears, to nearest tenth of degree, in left data display; also drift angle, to nearest degree, appears in right data display. NOTE Navigation information is now available  from  the  INS  for  display  in the pilot and copilot RMI's and on the pilot and copilot HSI's, as determined by  the  COURSE  INDICATOR  and  RMI select switches. (8) To fly selected INS course: 1.  Pilot's COURSE INDICATOR switch INS. 2.  Pilot's RMI select switch - INS. 3.    Horizontal  Situation  Indicators  (pilot's  and/or copilot's HSI) Steer toward indicators. 4.  CDU ALERT annunciator - Monitor. Observe     illumination     approximately     1.3     minutes before     reaching     point     for     automatic     leg     switch. Indicator flashes on and off after passing a way-point, if AUTO-MAN switch is in MAN. (9) Aided TACAN operation: NOTE If high accuracy alignment is required, wait  for  the  READY  NAV  light  before selecting NAV mode. 1.  Mode selector - NAV. 2.  Data selector - DSRTK/STS. 3.  Key 4 - Press. Observe right data display is 000004 and INSERT/ADVANCE pushbutton light is illuminated. 4.  INSERT/ADVANCE pushbutton Press. Observe   right   data   display   is   1-XX4   and   INSERT/ ADVANCE pushbutton light is extinguished. NOTE Every  30  seconds,  the  INS  will  select next eligible TACAN station in sequence     for     updating.          To     be eligible, TACAN station range must be between  5  and  150  nm  and  channel between 1 and 126. 5.  Data selector L/L WY PT or UTM WY PT. 6.  Keys 7 and 9 - Press simultaneously. Observe channel number of the TACAN station being used  for  navigation  flashes  on  and  off.    Data  displays indicate coordinates of station, selected via thumbwheel. 3-55