CHART WORK

• It is the plane below which all depths are published on a navigational chart
• It is defined as a level so low that the tide will not usually fall below it

• Gravity is one of the major force that create tide.
• It is caused by the gravitational forces exerted on the earth by moon & somehow the sun too.
• When the highest point in the wave(crest), reaches a coast, the coast experience a high tide.
• When the lowest point in the wave(trough), reaches a coast, the coast experience a low tide.
• The part of ocean which faces the moon experience a gravitational pull of moon.
• Gravity pulls the ocean towards moon and high tide occurs.

There are 3 types of tide:

• Diurnal tide: One high and one low tide each day
• Semi-diurnal tide: Two high and two low tide each day
• Mixed tide: Two unequal high and low tide

Flood tide is the tidal phase during which water move towards the shore, and,

Ebb tide is the tidal phase during which water move seaward.

Spring tide:

• It occurs when sun and moon are in line & pulling the ocean surface in the same direction, that means, at full moon or new moon
• Spring tides occurs as high tides are higher & low tides are lower, that means, range of tide is large
• It occurs twice each lunar month all year long

Neap tide:

• It occurs when sun and moon are at right angle & moon’s gravitational pull are cancelled by sun’s gravitational pull
• Neap tides have lower high tides and comparatively higher low tides, that means, range of tide is small
• It also occurs twice a month after 7 days of spring tide

Since, spring tide occurs at full moon or new moon

In ATT, the full moon is shown as ⚪

         & the new moon is shown as ⚫

So, we get the spring tide.

• It occurs when river empties into an ocean.
• It is a strong tide that pushes up the river against the current.

As we know, Tide is a vertical movement of water 

Whereas, Tidal Stream is a horizontal movement of water caused due to same astronomical causes, which causes the tide.

No, they are not same.

Tidal stream is the flow of water due to the change of tide, whereas, Current is the flow of water due to the wind.

They are pair of lights beacon used to indicate a safe passage for vessel entering a shallow or dangerous channel.

They may also be used for position fixing.

RACON : Radar beacons

• It is a radar transponder which emits a characteristics signal when triggered by a ship’s radar.
• RACON is triggered by both 3 cm & 10 cm radar.
• RACON signal appears on PPI as a radial line (series of dotted & dashes) originating at a point beyond the position of radar beacon.

RAMARK: Radar markers 

• It is radar beacon used to mark navigational hazard which transmit continuously or at interval.
• RAMARK signal appears on PPI as a radial line from the center.

Parallel indexing is a technique used as a measure to monitor the progress of a vessel on the track and to keep vessel at safe distance from the shoreline or rock.

(i) Appraisal: This is the process of gathering all the relevant information for the proposed voyage, including identifying and assessing the risk to ensure the safe voyage planning.

(ii) Planning: By using all information gathered during appraisal, the officer will prepare a detailed plan of voyage from berth to berth, including the areas where pilot will be on board.

(iii) Execution: The Navigating Officer execute the plan that has been prepared. All the factors like weather condition, traffic density etcetera are taken into account. Speed is adjusted such that ship is neither too early or late to its destination.

(iv) Monitoring: It is the act of checking the position of the vessel at a some interval of time. Parallel indexing are used when near the shoreline. Few other include visual bearing, radar fixes etc.

1. Admiralty Chart Catalogue 
2. Admiralty List of lights
3. Admiralty List of Radio signals 
4. Admiralty Tide tables 
5. Admiralty Sailing Directions
6. Navigational Charts
7. Routeing Charts
8. Security (Q-series chart) 
9. Load line chart
10. T & P notices in force 
11. Bridge Procedure Guide
12. Ocean passages of the world
13. Distance tables
14. Mariner’s Handbook – NP 100
15. Guide to Port Entry 
16. Manoeuvring Characteristics
17. SMS manual
18. SMS nav checklists 

Wheel over point (WOP) is a point where we give the rudder helm by considering the distance to the new course and ship’s turning characteristics (reaction time).

• Correction of ASD comes with weekly notices to Mariner.
• Updates may be cut and pasted directly into the book.

Formula:- 

V/R = 15/4 = 3.8° / min

Chapter 1 : Introduction 

Chapter 2 : Effective Bridge Organisation 

Chapter 3 : Passage planning

Chapter 4 : Duties of the Officer on watch

Chapter 5 : Operation and maintenance of bridge equipment 

Chapter 6 : Pilotage 

Appendices 

Appendix A : Dynamic Positioning (DP)

Appendix B : ECDIS carriage requirement

Appendix C : Checklist

Appendix D : Posters (wheelhouse)

Appendix E : Recommended industry publications.

Admiralty Sailing Direction (Pilot) provides essential information to support port entry and coastal navigation.

It splits across 75 volumes.

The contents of ASD include:- 

• Navigational hazard
• Buoyage 
• Pilotage 
• General regulations on country 
• Port facilities 
• Seasonal currents 
• Ice and climatic condition

Admiralty List of Radio Signal (ALRS) provides essential information on all aspects of maritime radio communication.

It is organised in 6 volumes.

The volumes are:- 

• Volume 1 : Maritime Radio Station (Part 1 & 2)
• Volume 2 : Radio Aid to Navigation (Part 1 & 2)
• Volume 3 : Maritime Safety Information (Part 1 & 2)
• Volume 4 : Meteorological observation stations
• Volume 5 : Global maritime distress and safety system
• Volume 6 : Pilot services, VTS and Port operations (Part 1 to 8)

All world are divided in 12 charted area.

Each charted area contains 12 seperate chart for each calendar month 

i.e. 12 × 12 = 144 charts 

The contents include:- 

• Wind roses
• Frequency and intensity of low pressure 
• Ocean currents 
• Sea and air temperature 
• Air pressure 
• Recommended track and distance 
• Ice information – maximum ice limits.