Mini-automatic radar plotting aid

This article is about the radar plotting aid. For the PMA aircraft parts trade association see Modification and Replacement Parts Association.

Mini-automatic radar plotting aid (or MARPA) is a radar feature for target tracking and collision avoidance. Targets must be manually selected, but are then tracked automatically, including range, bearing, target speed, target direction (course), CPA (closest point of approach), and TCPA (time of closest point of approach), safe or dangerous indication, and proximity alarm. MARPA is a more basic form of ARPA (automatic radar plotting aid).

Manufacturers use a variety of acronyms for the small crafts or yacht, e.g. MARPA (mini or manual ARPA, depending on which company you talk to) is the dominant one. MARPA, ATA (automatic tracking aid), and ARP (automatic radar plotting) all similar functions to ARPA. The major difference of this Radar plotting aids may not be fully equivalent to all ARPA performance standard of IMO approved type which is a mandatory requirement for large ocean-going ships. Therefore, they are less expensive for small craft.

References

• Maptech: Using ARPA, MARPA, and Radar with Chart Navigator Pro
• Raymarine: MARPA Target Tracking and Collision Avoidance
• Radar in the 21st Century