Using the radar
65
MARPA
Safety Notices
CAUTION: MARPA can improve collision avoidance when used
wisely. It is the user’s responsibility to exercise common prudence
and navigational judgement.
There are conditions where acquiring a target may become difficult. These same
conditions may be a factor in successfully tracking a target. Some of these
conditions are:
• The target echo is weak. The target is very close to land, buoys or other large
targets.
• The target or your own boat is making rapid maneuvers.
• Choppy sea state conditions exist and the target is buried in excessive sea
clutter or in deep swells.
• Choppy sea state conditions exist yielding poor stability; own boat’s heading
data is very unstable.
• Inadequate heading data.
Symptoms of such conditions are that acquisition is difficult, and the MARPA
vectors are unstable; the symbol wanders away from the target, locks on to
another target or changes to a lost target symbol.
If any of these conditions are present, acquisition and tracking may need to be re-
initiated or, in some cases be impossible to maintain. Improving the quality of the
heading data will reduce the effect of the other conditions.
Introduction to MARPA
You can use the Mini Automatic Radar Plotting Aid (MARPA) functions for target
tracking and risk analysis. MARPA improves collision avoidance by obtaining
detailed information for up to 10 automatically tracked targets and provides
continuous, accurate and rapid situation evaluation.
MARPA automatically tracks acquired targets, calculates target bearing and
range, true speed and course.
Each tracked target can be displayed with a vector depicting approximate target
speed (vector length) and course (vector direction). The target data can be
displayed on-screen in the MARPA Target databox; each target is continually
assessed, and you are warned if one becomes dangerous or is lost.
81238_1.book Page 65 Thursday, September 16, 2004 2:49 PM
Summary of Contents for H6
Page 56: ...42 Raymarine H6 Owner s Manual 81238_1 book Page 42 Thursday September 16 2004 2 49 PM...
Page 66: ...52 Raymarine H6 Owner s Manual 81238_1 book Page 52 Thursday September 16 2004 2 49 PM...
Page 88: ...74 Raymarine H6 Owner s Manual 81238_1 book Page 74 Thursday September 16 2004 2 49 PM...
Page 102: ...88 Raymarine H6 Owner s Manual 81238_1 book Page 88 Thursday September 16 2004 2 49 PM...
Page 106: ...92 Raymarine H6 Owner s Manual 81238_1 book Page 92 Thursday September 16 2004 2 49 PM...
Page 114: ...100 Raymarine H6 Owner s Manual 81238_1 book Page 100 Thursday September 16 2004 2 49 PM...
Page 120: ...106 Raymarine H6 Owner s Manual 81238_1 book Page 106 Thursday September 16 2004 2 49 PM...
Page 132: ...118 Raymarine H6 Owner s Manual 81238_1 book Page 118 Thursday September 16 2004 2 49 PM...
Page 146: ...132 Raymarine H6 Owner s Manual 81238_1 book Page 132 Thursday September 16 2004 2 49 PM...
Page 162: ...148 Raymarine H6 Owner s Manual 81238_1 book Page 148 Thursday September 16 2004 2 49 PM...
Page 178: ...164 Raymarine H6 Owner s Manual 81238_1 book Page 164 Thursday September 16 2004 2 49 PM...
Page 182: ...168 Raymarine H6 Owner s Manual 81238_1 book Page 168 Thursday September 16 2004 2 49 PM...
Page 192: ...178 Raymarine H6 Owner s Manual 81238_1 book Page 178 Thursday September 16 2004 2 49 PM...