Automatic Radar Plotting Aid

A maritime radar with Automatic Radar Plotting Aid (ARPA) capability can create tracks using radar contacts. The system can calculate the tracked object's course, speed and closest point of approach (CPA), thereby knowing if there is a danger of collision with the other ship or landmass.Development of ARPA started after the accident when the Italian liner SS Andrea Doria collided in dense fog and sank off the east coast of the United States. ARPA radars started to emerge in the 1960s and, with the development of microelectronics. The first commercially available ARPA was delivered to the MV Taimyr in 1969 and was manufactured by Norcontrol, now a part of Kongsberg Maritime. ARPA-enabled radars are now available even for small yachts.
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