Slide 24 of 94
Notes:
Dialogue: Each MLRS firing battery has a survey section, equipped with one PADS. It provides survey control for the current and planned platoon OPAREAs. Each launcher section is equipped with a GPS device (AN/PSN-11) PLGR.
Launcher crews use SCPs to initialize, update and calibrate the launcher PDS. Although M270 launchers do not require directional control, there must be horizontal and vertical position control in each of the platoon OPAREAs. There may also be a requirement for establishing SCPs for conducting PDS calibration. The survey section establishes these SCPs with the PADS by using 10-minute Z-VEL (zero velocity) corrections.
(PADS works by using accelerometers and gyros. Gyros determine the direction in which PADS is traveling and the accelerometers measure the distance. When you are traveling the accelerometers can't keep up for a very long period without losing accuracy (speed is not a factor). Therefore, the vehicle must be stopped every 10 minutes to perform a Z-VEL (zero velocity) correction. This gives the accelerometers time to catch up. Normally, for battalion survey sections perform a 10 minute Z-VEL and DIVARTYs perform a 5 minute Z-VEL (more accurate). It is important that PADS know where it is starting from and it is able to measure the azimuth and distance to where its been, the computer can then calculate a new set of coordinates for the new SCP).
