DAILY SYSTEM OPERABILITY TEST
The purpose of DSOT is to assess missile system readiness in its normal mode of operation. For most systems, this would be the AAW mode, although the specific functions tested may vary between systems. DSOT usually involves testing target detection and/or designation, acquisition, tracking, and missile firing. A typical DSOT is described in the following paragraphs. Figure 10-18 is a simplified block diagram of DSOT data flow.
Before the test sequence is started, each equipment station prepares for operation. Technicians follow a list of instructions provided at the beginning of the MRC test procedure. Most setups involve equipment turn-on actions and switch positioning. In some cases, the test conductor announces a particular equipment configuration.
In systems that test this function, a synthetic (artificial or man-made) target video is inserted in the 3-D search radar. The target is at a predetermined range, bearing, and elevation. These data are routed through normal distribution circuits. The target video is checked at the NTDS/WDS or WDS consoles. The test target is then entered into a WDS tracking circuit.
If the detection function is not tested, the NTDS/WDS or WDS operator initiates the test target at the TSTC. A GMFCS is assigned to one of the tracking channels. The accuracy of the designated position is checked at the radar set console. Position repeat back data are checked at the NTDS/WDS or WDS consoles.
Acquisition and Static Track
A test RF generator provides the fire control radar with a simulated target return signal. Radar jamming signals may also be provided. The scope display of the radar is monitored to see how well the radar can acquire the target. How much of the radar receiver is tested is determined by where the test signal is introduced. The test signal contains information needed for radar tracking, including angle, error, and range. Target
Figure 10-18.-Simplified DSOT data flow.
parameters are usually controlled by a test program, as previously mentioned. Control is also possible from an analog test set.
Launcher Loading and Missile Selection
After track is attained, the launcher goes through a loading sequence to place a training missile on the rail. SAFETY REMINDER: VERIFY THAT ONLY A TEST MISSILE HAS BEEN LOADED. Otherwise, the DSOT would result in the actual launching of a live missile. (Don't laugh, it HAS happened!)
Missile type and mode selection might also be tested at this time. The simulator of the test missile provides these functions.
During this phase of DSOT, two aspects of system operation are tested. The first is the FCS tracking of a dynamic target. The second is launcher assignment and synchronization to a computer-ordered position.
Target parameters are selected that simulate an incoming enemy aircraft. The fire control system is monitored to ensure smooth and accurate tracking. The launcher is assigned and the fire control problem solution verified by monitoring launcher and missile orders.
Engageability displays are observed at the weapons control area. Displays indicate when the target is within firing range and the launcher is in a clear firing bearing. If all conditions are correct, the firing circuit is closed (ITL). A proper firing indication is monitored at the launcher station and is verified at various weapons stations.
The launcher operator must initiate a missile-inflight condition. That is usually done by depressing a switch button which simulates the launcher rail is clear/empty. In effect, we electrically "lie" to the system, but it is necessary to continue the test.