Official navigation charts - Admiralty charts - are available from the United Kingdom Hydrographic Office(UKHO) through their chart agents, in paper and digital form. The UKHO also publishes the Admiralty List of Lights, Admiralty Sailing Directions, Admiralty Tide Tables, Admiralty Maritime Communications and a range of other books. Other types of chart and publication, in both paper and digital form are available from various private manufacturers. Admiralty charts are updated each week from Admiralty Notices to Mariners, while other suppliers' charts may be updated at less frequent intervals.
Notices to Mariners (NMs) to update Admiralty charts and publications are issued by UKHO. These NMs cover permanent changes to features shown on charts, temporary changes of long duration, and preliminary announcement of forthcoming significant changes. Port authorities and other bodies also issue their own Notices to Mariners to advise of local changes, and these will include notification of shorter-term temporary changes (such as lights being extinguished) and local events and marine works. The Northern Lighthouse Board (NLB) website gives a very useful update on lights and buoys in our area - go to the NLB site and click on Notices to Mariners.
The main UKHO website is www.ukho.gov.uk This has full details of all Admiralty products and services and how to obtain them. UKHO also operate a number of other sites of specific interest to leisure users. www.ukho.gov.uk/admiraltycatalogue has a full listing of charts and various ways of searching it. Each chart has a "thumbnail" view so you can get some idea of what it covers before you buy it, and a link to the NMs updating it.
www.nmwebsearch.com is where you can access the text of all Admiralty NMs. It has various search options easytide.ukho.gov.uk gives free tidal predictions for today and the next six days Among the search options is a graphical view that allows you to click on the nearest location to the place in which you are interested. www.admiraltyleisure.co.uk gives details of products designed specifically for the leisure user.
The UKHO is always interested to hear about changes to charted features that you may encounter in your cruises. They will always follow up reports, and a number of NMs are issued each year that result directly from information supplied by yachts. If you do spot something on a chart that needs to be updated, call UKHO on 01823 337900 and ask for the Helpdesk - they will then forward your call to the appropriate person. Alternatively, send a fax to 01823 284077 or email helpdesk@ukho.gov.uk.