CELESTIAL NAVIGATION Section CELESTIAL NAVIGATION Section 2222

Day’s Work at SeaDay’s Work at Sea

Prepared by: John C. HudsonSaanich Peninsula Squadron, VISD Jan 2006 / Rev. Jan 2007

Day’s Work at SeaDay’s Work at Sea

- uses most of navigational - uses most of navigational procedures learnt in this courseprocedures learnt in this course

- real world weather conditions - real world weather conditions often preclude sights being often preclude sights being taken at normal timestaken at normal times

- regardless, navigator must - regardless, navigator must maintain DR course at all times maintain DR course at all times and EP’s when prudentand EP’s when prudent

Responsibility of a NavigatorResponsibility of a Navigator

- navigator required to know - navigator required to know vessel’s position as accurately as vessel’s position as accurately as possible at all times to ensure possible at all times to ensure safety of vessel, passengers, safety of vessel, passengers, crew and cargocrew and cargo

- no universally accepted - no universally accepted standards of navigation at sea; standards of navigation at sea; each navigator must develop a each navigator must develop a daily proceduredaily procedure

Responsibility of a NavigatorResponsibility of a Navigator

daily procedure will depend on:daily procedure will depend on:

- particular vessel- particular vessel

- its location- its location

- prevailing weather- prevailing weather

- navigational equipment - navigational equipment avail.avail.

- orders from captain/owner- orders from captain/owner

Responsibility of a NavigatorResponsibility of a Navigator

- recommended that navigator - recommended that navigator takes daily dawn and twilight star takes daily dawn and twilight star FIX as well as noon RFIXFIX as well as noon RFIX

- supplement during day by sun - supplement during day by sun and/ or moon sights as neededand/ or moon sights as needed

- if so equipped, navigator should - if so equipped, navigator should obtain ship’s position by obtain ship’s position by electronic meanselectronic means

Responsibility of a NavigatorResponsibility of a Navigator

- for twilight FIXes, 3 body fix is - for twilight FIXes, 3 body fix is desirabledesirable

- run of 3 observations on each of - run of 3 observations on each of 3 bodies, averaging 3 bodies, averaging timestimes and and ““hshs” is good practice to improve ” is good practice to improve accuracy and eliminate bad sightsaccuracy and eliminate bad sights

- advanced planning and pre-- advanced planning and pre-calculation of expected positions calculation of expected positions is sign of efficient navigatoris sign of efficient navigator

Navigator’s Notebook and LogNavigator’s Notebook and Log

- navigator expected to record - navigator expected to record and retain all data to and retain all data to substantiate plotted positions substantiate plotted positions recorded in log and on chartrecorded in log and on chart

- these records should be readily - these records should be readily available for submission to available for submission to authorities in event of an enquiryauthorities in event of an enquiry

Navigator’s Notebook and LogNavigator’s Notebook and Log

- no specified method of - no specified method of maintaining such data; record maintaining such data; record may be simply in form of may be simply in form of continuous chronological account continuous chronological account of:of:

- navigational procedures - navigational procedures followedfollowed

- calculations made- calculations made

- positions determined- positions determined

Navigator’s Notebook and LogNavigator’s Notebook and Log

another format may use separate another format may use separate records for:records for:

- course, speed, times and - course, speed, times and positions of course changes and positions of course changes and

celestial observationscelestial observations

- log of position co-ordinates - log of position co-ordinates together with method of together with method of

determinationdetermination

Navigator’s Notebook and LogNavigator’s Notebook and Log

- example of deck log used in CPS coursesSee figure 16.12 on page 137

- deck log should contain complete account of voyage and is important reference document

Data to be submitted to Class Data to be submitted to Class InstructorInstructor

- successful completion of - successful completion of Day’s Day’s Work at SeaWork at Sea is pre-requisite of CN is pre-requisite of CN coursecourse

- class instructor must certify - class instructor must certify that this requirement has been that this requirement has been completedcompleted

- submission to include Plotting - submission to include Plotting Sheet, Sight Reduction sheets, Sheet, Sight Reduction sheets, Work sheets showing all Work sheets showing all calculations and Deck Logcalculations and Deck Log

Data to be submitted to Class Data to be submitted to Class InstructorInstructor

- all work should be arranged in - all work should be arranged in chronological orderchronological order

- for Deck Log, use blank DL01 - for Deck Log, use blank DL01 formsforms

- remarks column should contain - remarks column should contain concise information relevant to concise information relevant to navigational work navigational work (see Fig 16.12, page (see Fig 16.12, page 137)137)

Data to be submitted to Class Data to be submitted to Class InstructorInstructor

- courses, lines of position, FIXes, - courses, lines of position, FIXes, etc. should be plotted and etc. should be plotted and labelled according to CPS labelled according to CPS standards as shown in section 16standards as shown in section 16

- do not obscure lines with labels - do not obscure lines with labels or other recordingsor other recordings

- submit calculations separately - submit calculations separately on work sheetson work sheets

Numerical TolerancesNumerical Tolerances

- report zone time to nearest - report zone time to nearest minuteminute

- watch time to nearest second- watch time to nearest second

- position to nearest 0.1 minute- position to nearest 0.1 minute

- azimuth to nearest 0.1- azimuth to nearest 0.1 degreedegree

- set of current to nearest degree- set of current to nearest degree

- drift of current to nearest - drift of current to nearest 0.10.1 knotknot

- Great Circle distance to nearest - Great Circle distance to nearest milemile

Accuracy RequiredAccuracy Required

- answers are given for “Sienne - answers are given for “Sienne Cruise” on page 172 so work Cruise” on page 172 so work may be checked by student as it may be checked by student as it progressesprogresses

- exact duplication of co-- exact duplication of co-ordinate in plotted positions is ordinate in plotted positions is not expected, but if exceeds 0.1’ not expected, but if exceeds 0.1’ in L or Lo, calculation and plot in L or Lo, calculation and plot should be checkedshould be checked

Time of Completion of the Day’s Work Time of Completion of the Day’s Work at Seaat Sea

- this exercise should be started - this exercise should be started as soon as relevant sections are as soon as relevant sections are covered in classcovered in class

- “- “Sienne CruiseSienne Cruise” is very similar ” is very similar to Open Book portion of CN to Open Book portion of CN Course Examination, so important Course Examination, so important to fully understand and complete to fully understand and complete correctlycorrectly

- read section 22.6.1 carefully!- read section 22.6.1 carefully!

BEST WISHESBEST WISHESfor thefor the

SIENNE CRUISESIENNE CRUISEand the EXAMand the EXAM

The EndThe End