MT-3222 - Automatic Radar Plotting Aids (ARPA)

The expected outcome is that the student...	Supports STCW elements...
TOPIC - Review of plotting techniques uses plotting sheet and reflection plotter to construct the relative motion triangle, and identifies the sides and angles determines course, speed and aspect of other ships from true and relative plots determines CPA and TCPA from the true and relative plots determines changes in CPA and TCPA resulting from alteration of course and speed of "own" or target ship uses a relative plot to determine the alteration of course or speed needed to achieve a required CPA detects alteration of course or speed of a target and determines the alteration from a plot	21A3.05 21A3.08
TOPIC - Principal ARPA systems describes the different methods of displaying information, to include vectors, graphics, digital read-out, potential collision points (PCP), predicted areas of danger (PAD) describes the different ways in which targets may be acquired	21A3.01 21A3.03 21A3.13 21A3.14 21A2
TOPIC - IMO performance standards for automatic radar plotting aids (ARPA) outlines the IMO performance standards for ARPA describes the requirements for acquisition and tracking of targets describes the operational warning required lists the data which should be available in alphanumeric form explains that the accuracy standards for ARPA are based on sensor errors for equipment complying with IMO performance standards state performance standards for gyro and log inputs state performance standards for range and bearing accuracy and discrimination of radar	21A3.11 21A3.10 21A3.12 21A3.13 21A3.02
TOPIC - Acquisition of targets explains how ARPA acquires a target states that the criteria for automatic selection of targets are given in the set's instruction manual describes the criteria to be used for manual acquisition of targets states that the number of targets which may be acquired is limited explains that targets not posing a potential threat should be deleted from the tracker register if the limit on the number of acquired targets has been reached explains that target acquisition may be suppressed over certain areas and states when that facility should be used states that targets first appearing closer than the preset guard ring are not acquired and do not actuate alarms states the differences in automatic acquisition by area and automatic acquisition by guard zone.	21A3.13
TOPIC - Tracking capabilities and limitations describes how a target is tracked by ARPA explains that an acquired target may be "lost" if its echo fades temporarily describes the circumstances leading to "target swap" describes the effect of target swap on displayed data	21A3.04 21A3.11
TOPIC - Processing delays explains why there is a delay in the display of processed ARPA data after target acquisition explains the delay in the display of new data when the target ship maneuvers states that full accuracy of derived information may not be attained for up to three minutes after acquisition or maneuver of the target	21A3.11 21A3.06
TOPIC - Setting-up and maintaining displays selects an appropriate display presentation having regard to the required task and current situation correctly adjusts the radar controls for the optimum display of echoes checks that log and gyro compass are functioning correctly demonstrates the use of manual acquisition to select and monitor critical targets demonstrates the automatic acquisition and exclusion areas selects an appropriate time scale for vectors or graphics to produce information required explains how derived information differs, depending whether the sea stabilized mode or the ground stabilized mode is used selects the appropriate mode for the circumstances explains the use of echo-referencing (auto-drift) in the true motion mode	21A3.03 21A3.11 21A3.13
TOPIC - Representation of target information uses display in true and relative motion and demonstrates the use of true and relative vectors demonstrates the benefits of switching between true and relative vectors explains the graphic display of PCP and PAD assesses the threat of collision by forward extrapolation of vectors and by the use of PAD (s) explains how past positions of tracked targets are displayed explains that the results of trail maneuver are approximations depending on the model of "ownship" maneuvering characteristics states that the operator will refer to equipment manual for a description of maneuvering characteristics used, if any demonstrates the setting and acknowledgment of operational warnings describes the benefits and limitations of operational warnings uses area rejection boundaries where appropriate to avoid spurious interference	21A3.08 21A3.11 21A3.12 21A3.14 21A3.15
TOPIC - Errors of interpretation states that the use of vectors in the wrong mode is a common error checks information from vectors with numeric display explains that a "lost target" which is subsequently reacquired may temporarily show a course and speed suggesting an alteration when none has occurred explains that the PAD and PCP displayed apply only to "ownship" and targets and does not indicate mutual threats between targets states that the length of line from target PAD or PCP is not an indicator of target speed uses history displays in same mode as vectors states that a change of direction in the relative history display does not necessarily imply that the target has altered course explains that the incorrect interpretation of ARPA can lead to a dangerous misunderstanding of the traffic situation	21A3.04 21A3.11 21A3.15
TOPIC - Errors in displayed data states that errors in bearing are generated in the radar installation by: backlash, ship motion, asymmetrical antenna beam, and azimuth quantization states that errors in range are generated by: rolling of "ownship" and range quantization explains that the smoothing filter in the tracker combined with alterations in "ownship" course may temporarily produce unreliable indications states that errors will be introduced by inputs from compass and log describes the effects of heading and speed errors on derived information states that the smoothness of the displayed true history track gives some indication of satisfactory tracking by ARPA	21A3.11
TOPIC - System operational tests uses system of self diagnostic routines uses test programs to check performance against known solutions checks performance, including trial maneuver by manual plotting states action to take after malfunction of ARPA	21A3.12
TOPIC - Risks of over reliance on ARPA states that the use of ARPA does not relieve the officer of the watch from the need to comply with basic principles in keeping a navigation watch explains the dangers of relying on operational alarms to warn of the presence of other vessels or impending close quarters situations explains why small predicted passing distances must not be relied upon states that sensor input alarms only operate on failure of input and do not respond to inaccurate inputs	21A3.11 21A3.10 21A3.02
TOPIC - Obtaining information from ARPA displays demonstrates ability to obtain information in both true and relative motion display identifies critical targets determines relative course and speed of target - equipment manual determines CPA and TCPA of target determines true course and speed of target interprets displays of past positions for detecting changes in course and speed of target operates trial maneuver facility to check validity of intended alteration of course or speed	21A3.05 21A3.06 21A3.05
TOPIC - Application of navigation rules analyzes displayed situations, determines and executes action to avoid close quarters situations monitors subsequent situation and resumes original course and speed when safe to do so	21A3.07