Lights, buoys and radio aids

Virtual aid to navigation

Also written: V-AtoN

A buoy that exists only as an AIS signal — shown on electronic charts and radar, with nothing physically in the water.

A virtual aid to navigation is broadcast from a shore station over AIS and appears on electronic chart and radar displays as a buoy symbol. Authorities use them to mark new dangers quickly — a fresh wreck, a pipeline repair, a temporary exclusion zone — before a physical buoy can be laid, or where laying one is impractical.

A ship without AIS on its display will not see a virtual aid at all, which is why the warning announcing it matters.

What the archive shows

2 messages in this archive use “Virtual aid to navigation”, the earliest issued 2019-06-07 and the latest 2023-11-07. None of them is in force in the latest lists we collected. A hazard reported again and again counts once per message.

2 recorded messages form a small sample; the warning type breakdown should be read as individual records rather than a pattern.

Located messages that use it fall in 2 sea areas; the most frequent are Persian Gulf (1) and Coral Sea (1).

By warning series: HYDROPAC 2.

Messages using it, by year of issue

'19
'20
'21
'22
'23

Where it appears · 2 sea areas

How it reads in recent messages

  1. HYDROPAC 3504/23 · Other · Coral Sea2023-11-07

    ARAFURA SEA. AUSTRALIA. DNC 05. VIRTUAL AIS AID TO NAVIGATION ISOLATED DANGER MARK ESTABLISHED IN 10-34.33S 142-04.04E.

    Virtual AIS aid to navigation isolated danger mark established in 10-34.33S 142-04.04E
  2. HYDROPAC 1851/19 · Other · Persian Gulf2019-06-06

    …OFF SHORE OIL TERMINAL IN 25-34.61N 055-24.16E INOPERATIVE 10 JUN THRU 20 AUG. 2. VIRTUAL AIS AIDS TO NAVIGATION ESTABLISHED IN: A. SPM, 25-34.61N 055-24.16E. B. PL1, 25-33.75N…

    All navigation aids at sharjah off shore oil terminal in 25-34.61N 055-24.16E inoperative 10 jun thru 20 aug

Often in the same message

Related terms

AIS (Automatic Identification System)
The radio transponder system that broadcasts a ship's identity, position, course and speed — and can mark a hazard with a virtual beacon.
Dangerous wreck
A sunken vessel close enough to the surface to endanger ships, or wreckage reported in the water.
Off station / missing buoy
A buoy that is not in its charted position — dragged, damaged, missing or removed.

Warning types that use it

Counts cover the messages in this archive that use the term, recounted 2026-09-24; see coverage for what is collected and since when. Not for navigation — follow official NAVAREA and coastal broadcasts.

Virtual aid to navigation — what it means in a navigational warning · seahazards