Easy to do,
1/ press MENU to select “DISPLAY FIX” on the ISIS ( scroll through past SPD BUG 1, SPD BUG 2, SET ALT BUG, DISPLAY METERS, SET BARO UNIT and DISPLAY NAV )
2/ get the LAT LON from the FM DATA menu on the general menu bar. Select WAYPOINT and insert the airport and runway you want, it displays the runway threshold LAT LON.
3/ insert data into the ISIS.
simple
it will show you BRG and DIST to that waypoint based on IRS 3. So if you have any IRS drift it will possibly be incorrect by the amount of IRS 3 error,
Last edited by ACMS; 13th Nov 2019 at 12:15.