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How to apply the updates to your charts

Ali NMs should be recorded in Ink against the appropriate chart number in NP133A Thereafter all charts in current use and those required for any forthcoming passage should be updated immediately; other charts held on board should then be updated as time allows.

Where morę than one copy of a chart is held, either each copy should be recorded separately in NP133A or a pencil notation should be madę against the chart number indicating how many copies are held. It is important that all copies are maintained consistently so as to avoid the possibility of a copy that has not been updated being used.

The principles, practices and conventions of chart updating are illustrated by the following examples. Though reference is madę to the tracing in the examples given, always refer to the Admiralty Notice to Mariners text which is the primary source. By reading the NM whilst looking at the chart in question you will avoid the risk of deleting information which otherwise could have been used to complement the new information being inserted.

It should be noted that a tracing is only a guide to illustrate the update and to pin-point a position. Special symbols are used on the tracing to indicate insertions and deletions; these should NOT be copied faithfully onto the chart. The following examples will point out mistakes which can be madę if the information you are inserting on the chart is copied from a tracing. If tracings are used, these should be stored by chart number so that in the event of a change of passage plan any charts that are required but have not been updated can quickly be brought up-to-date. Tracings should always be filed by chart number. That way all the relevant information for any particular chart is kept together and, if that chart is cancelled or replaced by a New Edition or a New Chart, all the old tracings reiating to that chart can be destroyed.

There is not an example of an NM Błock. These should be aligned accurately and stuck onto the affected charts. It is important to remember to completely remove the enclosing black linę around the limits of the area of a błock before sticking it onto the chart; there is normally at least 5mm inside the linę with no new or deleted information on it. Care should be taken that new błock information does not obscure parts of previously inserted updates (for example, where a sounding has been inserted under the new błock but arrowed-in to a position outside it).

The following procedurę will help you avoid making mistakes:

•    Using the information in the NM (in conjunction with the tracing, if you have it), apply the update to the chart.

•    Check what you have done.

•    When you are satisfied that you have correctly followed the instructions of the NM (and only then) write the NM number in the bottom left hand corner of the chart as a record of the completed update. It is dangerous to insert the NM number in the bottom left hand corner of the chart before you have updated the chart. The year datę for the current year of NMs should be underlined so that it is not confused with an NM number

•    When you have completed all the steps above, cross through the NM number adjacent to the chart in your NP133A or similar record.

For further advice you should ask your Admiralty Chart Agent.

Any charts held on board that are not, and will not, be maintained up-to-date should clearly be marked “NOT TO BE USED FOR NAVIGATION”.

Explanation of Terms used in Notices to Mariners

The main text of the update starts with one of the following five commands, usuafly in the order shown:

INSERT is used for the insertion of all new data or, together with the DELETE command, when a feature has moved position sufficiently that the MOVE command is inappropriate.

AMEND is used when a feature remains in its existing charted position but has a change of characteristic, for exampie:

Amend light to, FI.3s25m10M    32*36-90S., 60°54' 18E.

When oniy the rangę of a light changes:

Amend rangę of light to, 10M    32°36-90S.. 60°54' 18E.

SUBSTITUTE is used when one feature replaces an existing feature and the position remains as charted. The new feature is always shown first, for example:

Substitute    xx for yy (where xx is the new feature)

MOVE is used for features whose characteristics or descriptions remain unchanged, but they are to be moved smali distances, for example:

Move    No 3 light-buoy from:    56°00'*62S., 4°46'-47E.

to:    56°00-30S., 4°46-35E

DELETE is used when features are to be removed from the chart or, together with the

INSERT command, when features are moved a significant distance such that the MOVE command is inappropriate.

Explanation of Symbols and Instructions on Tracings

Insertion:    Information to be inserted will be boxed. The position of the insertion is shown as

a smali circle containing a dot at its centre. An arrow will be shown from the box to the circle (-»->). Sometimes clarification may be required regarding what should be inserted or deleted. This is often the case with a substitution where words such as “in lieu” may be added to the tracing to assist those carrying out updates.

Deletion:    Information to be deleted will be boxed and hatched out by diagonal lines. A deletion

symbol (<7) will be annotated next to the boxed area. Where a cautionary notę is being deleted, the words “Delete + the title of the notę” will be inside the hatched area.

Linear features: Short lines are used to indicate the tuming points of linear features such as pipelines, cables or area limits thus:--,——**

Plotting from Tracings on a Chart

The positioning of tracings should always be checked carefully using three methods, as follows:

• Latitude and Longitude lines shown

• Location on Chart (e.g.

)

• Other fltting marks shown such as soundings or prominent features

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