Automatic radar plotting aid

A typical shipboard ARPA/radar system.

A marine radar with automatic radar plotting aid (ARPA) capability can create tracks using radar contacts.[1][2] The system can calculate the tracked object's course, speed and closest point of approach[3] (CPA), thereby knowing if there is a danger of collision with the other ship or landmass.

Development of ARPA started after 1956, when the Italian liner SS Andrea Doria collided with the MS Stockholm in dense fog and sank off the east coast of the United States. ARPA radars started to emerge in the 1960s, with the development of microelectronics. The first commercially available ARPA was delivered to the cargo liner MV Taimyr in 1969[4] and was manufactured by Norcontrol [no], now a part of Kongsberg Gruppen. ARPA-enabled radars are now available even for small yachts.

  1. ^ The dictionary definition of contact at Wiktionary
  2. ^ BOLE, A., DINELEY, B., WALL, A., Radar and Arpa manual. Oxford, Elsevier, 2005, p. 312.
  3. ^ The dictionary definition of closest point of approach at Wiktionary
  4. ^ "Kongsberg Maritime History". Kongsberg Maritime. Retrieved 2009-03-28.