DEAD RECKONING AND ESTIMATED POSITION


RYA CHART 3 and TRAINING ALMANAC Use variation 6° W, the deviation table and computation of rates table where required. All times as shown


1.


How are maritime time zones denoted, and how would a location with standard time one hour ahead of UT be designated?


2. What is the ISO standard for denoting time zones? 3.


a) 1723 SPDST b) 2000 DST


4


Using the log extract below, plot the DR at 2020 SPDST. Date


Time


Saturday, 4th May


2000 SPDST 2020 SPDST 5


Log 0.0


4.0 350


Express the following times in UT (all time zones are given in the maritime system or the abbreviations used within the training exercises and defined on the back page of this booklet).


Co°(C) Wind 350


SE3 SE3


Leeway Depth Notes 00°


20m 00°


Using the log extract below, plot the estimated position at 1550 SPDST. Date


Time


Sunday, 23rd June


1450 SPDST 1550 SPDST


Log 12.2


19.2


Co°(C) Wind 270


E3 270 E3 00° 56m


Position: 45°51´.77N 005°49´.36W


Plot DR (tidal direction and rate negligible).


Leeway Depth Notes 00°


60m


105m Position: 45°55´.96N 005°37´.27W


Estimate position using tidal K


6.


a) Using the log extract below, plot the estimated position at 1425 SPDST. Date


Time


Saturday, 12th October


1355 SPDST 1425 SPDST


Log 11.4


17.9


Co°(C) Wind 300


W2 300 W2 00°


Leeway Depth Notes 00°


22m 20m


Position: 45°47´.41N 005°42´.53W


Estimate position using tidal N


b) What was the vessel’s COG and SOG?


12


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