Motion of Observer Test Cases Last updated: July 4, 2017 Speed - motion of observer speed in knots Time - time the site is being advanced or retarded usually to a common fix time Track/course - true course of ship Zn - true azimuth to observed body A/R - is site is to be Advanced or Retarded to a common fix time Zn RB - body's relative bearing, clockwise, to body from bow Body - observed body's general position relative to ship Zn-TR - relative bearing from bow clockwise to azimuth of body Delta - MOO correction to be applied to Ho or Hc (sign is critical) and if advancing or retarding Rule when applying correction - can apply to Ho or to Hc (but not both), signs will be opposite Effect of LOP - MOO correction's effect on LOP Towards/Away from body's GP -------------------------------------------------------------------------------- Tules to Speed Time Track/ Polhemus Apply Effect on Knots Mins Course Zn A/R Zn RB Body Zn-TR Correction Correction LOP -------------------------------------------------------------------------------- 900 4 000° 000° A 000° forward 00° 60.0' +Ho -Hc Toward 900 4 000° 180° A 180° behind 00° 60.0' -Ho +Hc Away 900 4 010° 190° A 180° behind 00° 60.0' -Ho +Hc Away 650 1 010° 250° A 240° behind 60° 5.4' -Ho +Hc Away 700 4 015° 060° A 045° forward 45° 33.0' +Ho -Hc Toward 900 4 045° 135° A 090° side 90° 00.0' +Ho -Hc Toward 900 4 045° 225° A 180° behind 00° 60.0' -Ho +Hc Away 800 4 065° 345° A 280° forward 80° 09.3' +Ho -Hc Toward 500 4 075° 270° A 195° behind 15° 32.2' -Ho +Hc Away 600 4 080° 020° A 300° forward 60° 20.0' +Ho -Hc Toward 050 1 082° 152° A 070° forward 70° 00.3' +Ho -Hc Toward 800 4 090° 180° A 090° side 90° 00.0' +Ho -Hc Toward 900 4 090° 270° A 180° behind 00° 60.0' -Ho +Hc Away 300 4 130° 130° A 000° forward 00° 20.0' +Ho -Hc Toward 500 4 135° 045° A 270° side 90° 00.0' +Ho -Hc Toward 900 4 160° 280° A 120° behind 60° 30.0' -Ho +Hc Away 900 4 045° 305° A 260° behind 80° 10.4' -Ho +Hc Away 700 4 260° 055° A 155° behind 25° 42.3' -Ho +Hc Away 300 1 130° 070° A 300° forward 60° 02.5' +Ho -Hc Toward 700 4 180° 090° A 270° side 90° 00.0' +Ho -Hc Toward 400 4 180° 180° A 000° forward 00° 26.7' +Ho -Hc Toward 900 4 190° 010° A 180° behind 00° 60.0' -Ho +Hc Away 800 4 210° 190° A 340° forward 20° 50.1' +Ho -Hc Toward 900 4 225° 045° A 180° behind 00° 60.0' -Ho +Hc Away 300 4 270° 075° R 165° behind 15° 19.3' +Ho -Hc Toward 900 4 270° 090° R 180° behind 00° 60.0' +Ho -Hc Toward 700 4 345° 065° R 080° forward 80° 08.1' -Ho +Hc Away 900 1 000° 000° A 000° forward 00° 15.0' +Ho -Hc Toward -------------------------------------------------------------------------------