Marine Guidance Note - MGN 166 (M + F)

MGN 166 (M + F) - Guideline for Voyage Planning


What are the Four Elements to a Passage Plan?


Appraisal
Planning
Execution
Monitoring


Appraisal, what is this?
When you gather as much safety and navigation information to give you a safe voyage.



What type of information does this involve?
The tides
Tidal streams
Under-keel allowances
Information from pilot books/sailing directions
Chart dangers (rocks, shallow water oil-rigs etc.)
Traffic schemes
Weather information (shipping forecasts)
Possible areas of restricted visibility
Any areas, which would involve an area of high traffic density


Planning, what is this?
Planning out the intended voyage, using all the information from Appraisal


What have you to do to make a plan of your voyage?
Plot the intended voyage making sure it is safe, and that the plan has been checked out by the master of the vessel, use way points, parallel indexing , courses, distance to steam on each leg, and by using all the information that you Appraised


Execution, what is this?
The master should find out how long his intended voyage should take, making sure he has enough water and fuel for the voyage
He should take into account any weather conditions expected on the voyage
Any areas of high traffic density that would make him deviate from his course (he should if possible make a plan to keep well clear of these areas)


Monitoring, what is this?
This is the act of checking your position often on a chart and that you remain in a safe distance from any danger areas (land)
Parallel Indexing should be used when you are alongside any hazards to maintain a safe distance


What is Parallel Indexing?
This is done by using your radar and V.R.M. (Variable Range Marker) and putting a distance on to it , as long as this distance is not breached, then your vessel should be in safe water


What is the purpose of Parallel Indexing?
To make sure your vessel is a safe distance away from any navigation hazards 


How do you parallel index using radar?
By using your heading marker and slide it over towards the side that has the obstruction and using your V.R.M. and measuring the distance you need and put the heading marker onto the V.R.M. 


What would you do if you had to parallel index off a point of land at 2 miles but the radar says your 1.7 miles from the point of land?
Alter off the land until you where 2 miles from the point of land, never breech what distance you had to keep off an obstruction


Oral Exam Questions


Q1. What distance would you parallel index off the land or any obstacles that's in your passage plan?
A1. At least 2 miles depending on the depth of water at that obstacle and any dangers to the ship


Q2. You've made a passage plan up for a voyage from Aberdeen to Egypt, how will you find out the state of the tide in the area your going too?
A2. By using the tidal diamonds that's on the chart of the area your going too


Q3. Why is it important to keep your charts up to date?
A3. Incase any new obstructions endanger your vessel, sunk vessel with her masts above the water, well-heads, new approaches to a harbour, oil-rig shifted position Etc.


Q4. How do you correct your charts up to date?
A4. By using the Cumulative Notices to Mariners and cross referencing them against the numbers of past corrections on the bottom left hand side of your chart.


Q5. What would you do if there was a correction missing?
A5. Find out the correction number and what issue of the Weekly Notices to Mariners it was contained in and enter it and put the correction number in at the bottom left hand side of the chart then sign it and date it.


Q6. What is Position fixing?
A6. By using your GPS and taking the lat/long and placing this onto a chart


Q7. How can you Position fix your position on a chart if you only have a radar, charts and a magnetic compass 2 miles from a point of land?
A7. By taking a compass bearing of the point of land and changing this to a true bearing then reversing the true bearing, now draw a line with the true reversed bearing from the point of land and measure off 2 miles this will give you an approximate fix


Q8. What publication would you find all the charts of the world?
A8. Admiralty World Charts