ARMY TM 9-6675-349-12&P
MARINE CORPS TM 11039A-12&P
3-11. Configuration - Continued
(a) Measure the distances shown to be input into IPADS. Measurements are to be made from the
reference point on the IPADS frame to the location on the ground where the plumb bob is
dropped. The IPADS reference point is located at the center of the alignment hole on the bottom of
the IPADS frame, on the BCU side.
NOTE
All lever arm entries must be in centimeters to the nearest millimeter.
(b) On the VEHICLE TYPE page, enter the lever arm values.
c.
Survey Order.
IPADS supports two orders of survey: fourth order equivalent (4TH) using five-minute intervals between
ZUPTs; and fifth order equivalent (5TH), using ten-minute intervals between ZUPTs. To obtain IPADS
specified accuracy for battalion survey, the operator must perform 5TH order survey. For division artillery
survey, the operator must perform 4TH order survey. Current survey order is shown in second field of
mode line. Perform the following steps to change survey order:
Scroll to SURVEY ORDER on MENU and press ENTER. Function key line will display F1-4TH, and F2-
5TH. Press function key corresponding to mission survey order. MENU is displayed with selected survey
order shown on the mode line.
d. Ellipsoid and Datum.
CAUTION
Ellipsoid and datum can be changed at any point during a mission. Datum
shifts have unknown associated errors. Do not initialize and close IPADS
surveys at SCPs on different datums. SCPs on different datums likely were
established by different, unconnected surveys. Closing at an SCP on a
different datum may introduce significant error into adjusted coordinates.
3-20