Notices to Mariners

USE OF AIS AS AN AID TO NAVIGATION (ATON)

03 - 2013

Issue Date: Monday 31 December 2012

Aid:

Area: AIS

The General Lighthouse Authorities_[1] (GLA) are continuing to provide AIS AtoN at selected fixed and floating stations on the coasts of Great Britain and Ireland.

AIS AtoN are Aids to Navigation under the Merchant Shipping Acts and as such Statutory Sanction for their provision is required from the General Lighthouse Authority for the area in which they are established. Application forms are available on www.cil.ie.

It is considered appropriate at this time to repeat some guidance to mariners on the purpose of AIS AtoN and what they may expect to see on some of the available displays.

Displays & Symbology

The IMO mandatory carriage requirement for Class A_[2] AIS display is the Minimum Keyboard Display (MKD) which displays the data in alphanumeric form.

The information available to mariners will be dependent on their display system and not all transmitted information may be displayed. Mariners are encouraged to install systems that provide AIS overlay on ECDIS and Radar.

It is important to bear in mind that not all vessels are equipped with AIS. Of those vessels that are AIS equipped the displays available can range from no display on some Class B_[2] units, through the mandatory Class A MKD, to full ECDIS and Radar overlay. In the absence of ECDIS or Radar overlay users will not be able to fully utilise AIS AtoN functionality. There is also a variance on information that will be displayed by different manufacturers on ECDIS or Radar equipment.

The symbology that may be displayed on nautical charts, display systems and MKD is summarised below.

Nautical Charts

On nautical charts, AIS AtoN are indicated by a magenta circle, surrounding the existing AtoN symbol and an adjacent legend stating AIS. The font will   be straight for fixed AtoN and italic for floating AtoN.

By Order, Yvonne Shields Chief Executive.