Passage planning Flashcards
Voyage Planning
Before proceeding to sea, the master must ensure that the voyage has been planned using appropriate nautical charts and publications.
The plan should identify a route that takes into account relevant ships’ routeing systems, ensures sufficient sea room for safe passage, anticipates navigational hazards and adverse weather conditions, and considers marine environmental protection measures.
Principles of a passage plan
The purpose of passage planning is to develop a comprehensive navigation plan for
the safe conduct of the ship from berth to berth.’
The plan for the intended passage should identify a route that:
- Recognises hazards and assesses associated risks and decision points
- Ensures that sufficient sea room and depth of water is available
- Includes appropriate position fixing opportunities and intervals
- Complies with relevant reporting requirements and routeing measures for
ships - Considers anticipated traffic and weather conditions
- Complies with all applicable environmental protection measures.
What are the four stages of a achieving a safe passage plan
APEM
Appraisal
Planning
Execution
Monitoring
Appraisal Stage
Gathering of all the relative information and assesing relevant information required for the intended passage
- Navigation
- General - Operational
- Environmental
- Contingency
Planning Stage
Developing and approving a passage plan based on the outcome of the appraisal of all relavant information
Execution
Briefing the bridge team on the passage plan. Navigating the ship in accordance with the passage plan.
Monitoring
Checking progress of the ship against the passage plan
Publications for Passage planning
- Sailing directions
- Notices to mariners
- Port guides
- ALRS volumes
- Load line chart
- Ocean passage/routeing charts and guides
- Maritime security charts
- Tide tables and tidal stream atlase
Factors for UKC
- Source data
- Accuracy of the echo sounder
- Nature of the bottom
- Manoeuvrability of the vessel
- Ability to use PI lines
- Pipe lines and other obstructions in the area
- Squat of the vessel
How often should you fix your postion
The frequency of the position fix, as a maximum, should be such that the ship is kept free from danger between fixes and if a deviation occurs, avoiding action can be taken to guarantee the safety of the ship.
The frequency of fixing should depend on the distance from navigational hazards and the time the ship would take to run into danger before the next fix.
This depends mainly on the ships speed.
Executing the Passage Plan consideration
Having finalised the voyage or passage plan, as soon as time of departure and estimated time of arrival can be determined with reasonable accuracy. The voyage or
passage should be executed.
Consider
* The reliability and condition of the vessel’s navigational equipment
* Estimated times of arrival at critical points for tide heights and flow
* Daytime versus night-time passing of danger points, and any effect this may
have on position fixing accuracy
* Traffic conditions, especially at navigational focal points
* Meteorological conditions, (particularly in areas known to be affected by
frequent periods of low visibility) as well as weather routeing information
Weather routeing
Weather routeing allows the Master and the bridge team to follow a passage plan that avoids the worst weather in the interest of safety and fuel consumption efficiency.
Weather routeing predicts the movement of weather systems associated with poor conditions and rough seas. The most favourable route is then planned, taking these systems into consideration.
The main benefits of weather routeing are:
* Increased safety:
* Better conditions for cargo or passengers;
* Fuel and time savings;
* Reduced costs overall.
Passage plan briefing
A briefing should be held to make sure that all bridge team members understand their
role in executing the passage plan. The briefing should address the factors identified
in checklist
Before sailing, all of the bridge team should be appropriately briefed and should confirm their understanding of the passage plan.
Amendments to routes
Planning should be updated if the intended route is amended to reflect changing circumstances and conditions before or during a passage.
Monitoring the passage plan
Compliance with the passage plan should be closely monitored by the OOW:
- To check that the ship’s position is maintained within an authorised cross track
error, including following alterations of course to avoid a collision or waypoints - By fixing the ship’s position at a frequency based on existing conditions and
the proximity of navigational hazards - By cross-checking the ship’s position using all appropriate means, including:
- By visual and/or radar fixing techniques using ranges and bearing of charted
objects - By echo sounder to monitor charted depths and contours
- By monitoring the integrity of information displayed on navigational
equipment
Monitoring should be undertaken using appropriately prepared electronic or paper
charts.
Monitoring techniques
The following visual techniques should be used when monitoring the passage in
coastal and pilotage waters or the safety of the ship at anchor:
- Bearings of charted objects to fix the position
- Heading transits, which can provide a leading line along which a ship can
safely steer - Beam transits, which can provide an additional check when altering course
- Clearing bearings, which can be used to check that a ship remains in a safe
area - When charted features visible by radar appear on the display, radar can be
used for monitoring. The following techniques should be used for passage in
coastal and pilotage waters, particularly in conditions of restricted visibility or
at night: - Parallel indexing recommended to ensure the ship’s track is maintained
- Radar bearings and Radar ranges.
