ARPA Exam Questions with Answers (100% Correct
Answers)
What does ARPA stand for? —ANS: Automatic Radar Plotting Aid
Which of the following best describes the function of ARPA? —ANS: Automating
Radar target acquisition, tracking and plotting
What is one of the primary purposes of ARPA according to IMO Performance
Standards? —ANS: Reducing workload by providing automatic target information
In what way does ARPA contribute to navigational safety? —ANS: By facilitating
collision avoidance through automatic tracking and plotting
What distinguishes ARPA from manual radar plotting? —ANS: ARPA enables
simultaneous tracking of multiple targets automatically.
According to the IMO, what was the primary reason for developing ARPA? —ANS:
Tor reduce the workload of RADAR observers and enhance collision avoidance.
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How does ARPA benefit larger vessels compared to traditional radar plotting
methods? —ANS: By enabling simultaneous tracking of multiple targets with minimal
effort.
Which type of vessels are commonly equipped with Electronic Plotting Aids (EPA)
instead of ARPA? —ANS: Fishing Boats
What is the main difference between ARPA and EPA? —ANS: EPA requires manual
input for target plotting while ARPA is automatic.
How does ARPA improve collision avoidance capabilities? —ANS: by predicting
future positions of nearby vessels
Which organization sets the standards for ARPA functionality? —ANS: IMO
What is the role of ARPA in relation to the radar observer's workload? —ANS: ARPA
reduces workload by providing automatic target information
How does ARPA contribute to situational awareness? —ANS: By identifying potential
hazards in the ship vicinity
Which feature of ARPA makes it particularly useful in areas of high traffic density? —
ANS: capacity to simultaneously track multiple targets.
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What is the main advantage of ARPA over traditional radar plotting methods? —ANS:
ARPA can track multiple targets automatically.
Which display type does not suffer from image distortion near the edges of the screen?
—ANS: LCD Flat Panel
What information can modern displays present alongside radar presentations? —ANS:
Target data
What was the limitation of the early standalone ARPA units in terms of data
processing? —ANS: Could only process range and bearing.
What development led to the introduction of automatic radar tracking on large
commercial vessels? —ANS: Digital Microprocessors
What is the purpose of a Doppler speed log in ARPA systems? —ANS: To measure
own ship speed
What is the primary advantage of using a trackball, mouse pad, or joystick to access
radar andARPA functions? —ANS: Simplification of user interface
What system is used to define the location of a contact in terms of range and bearing?
—ANS: Polar coordinate system
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Which display type is mandated for all ARPAs by the IMO? —ANS: Flat Panel LCD
How does ARPA determine if a radar contact contains a possible target? —ANS: By
analyzing the signal strength and persistence within each cell.
According to the IMO, how many targets must an ARPA equipped only with manual
acquisition be capable of tracking simultaneously? —ANS: 10 targets
How is manual target acquisition typically initiated? —ANS: By pressing plot or
acquire button
What action does the radar observer take to initiate tracking of a target in manual
acquisition mode? —ANS: Moving the cursor over the contact echo and selecting
What appears on the radar display to indicate that ARPA is tracking a target? —ANS:
A bracket or circle symbol
What does ARPA look for within the tracking gate during each radar antenna sweep?
—ANS: Evidence of the target
What type of data does the ARPA processor begin to collect after acquiring a target? —
ANS: Position Data
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