Surveys

Underwater operations in progress until 27 dec by M/V ocean guardian in area bound by 16-04.71N 119-42.50E,…

South China Sea · HYDROPAC 3891/23

What this record establishes

Archived notice · 2023-12-28 00:01Z

This notice comes from the historical archive. Its archived status does not establish when or how the reported situation ended.

Source and dates
NGA MSI broadcast-warn JSON (archive, frozen 2024-05) · NAVAREA XI 446/23 120232Z DEC 23.. Issued 2023-12-12 05:40Z. First collected 2026-08-17 13:38Z; last seen in collection 2026-08-17 15:46Z. Collection dates record ingestion, not a new incident or a fresh field observation.
Location covered
South China Sea. The map shows an area described by the warning; the listed coordinate is its representative center. Check the original wording for limits and qualifications.

Current notices and reporting history in the South China Sea →

issued
2023-12-12 05:40Z
status
Archived notice
self-cancels
2023-12-28 00:01Z
authority
NAVAREA XI 446/23 120232Z DEC 23.
NAVAREA
NAVAREA XI · named as the source of this relay
sea
South China Sea
position
15.929, 119.624
vessel
M/V OCEAN GUARDIAN · 3 messages
source
NGA MSI broadcast-warn JSON (archive, frozen 2024-05) · first seen 2026-08-17 13:38Z

Original warning text

SOUTH CHINA SEA.
PHILIPPINES.
DNC 23.
1. UNDERWATER OPERATIONS IN PROGRESS
   UNTIL 27 DEC BY M/V OCEAN GUARDIAN
   IN AREA BOUND BY
   16-04.71N 119-42.50E, 16-02.72N 119-23.53E,
   15-45.04N 119-38.85E, 15-46.04N 119-47.43E.
   WIDE BERTH REQUESTED.
2. CANCEL THIS MSG 280001Z DEC 23.

Reading this warning

DNC (Digital Nautical Chart)
A reference to one of the regions of NGA's Digital Nautical Chart, used to tell the reader which charts a warning affects.
Underwater operations
Divers or remotely operated vehicles are working below a vessel that cannot easily move out of the way.
Area bound by
Introduces a list of positions that are the corners of an area — the polygon the warning applies to.
Position (degrees and minutes)
How warnings write positions: degrees, a hyphen, then minutes, with N/S and E/W — 49-40.8N 003-43.8W.
Wide berth requested
Keep well clear — or, when a distance is given ("TWO MILE BERTH REQUESTED"), at least that far away.
CANCEL THIS MSG
The warning's own expiry: a line telling the reader when the message cancels itself.
Date-time group (DTG)
A compact UTC timestamp — day, hour and minute followed by Z — such as 201500Z for the 20th at 15:00 UTC.

All warning terms →

Collected reports in this area · survey operations

3 within 180 nm since 2022 · 0 in the last 12 months · 0 listed in force now

22
23

Counts include repeat notices about the same situation. NGA archive coverage ends 2024-05; live collection began 2026-08-17. The period between them is incomplete. An empty year is not evidence that no hazards occurred.

Month of issue in the collected archive

J
F
M
A
M
J
J
A
S
O
N
D

All available years combined. Uneven collection and repeat bulletins affect these counts; this chart does not measure the seasonality or probability of incidents.

Nearby notices listed in force · within 120 nm

Worldwide in the collected sources

56 survey operations listed in force · see all

Record snapshot 2026-10-03 03:08Z; source collection times vary.

Surveys

Hydrographic and scientific survey vessels, often towing long arrays. All current survey operations →

Not for navigation. This is a re-rendering of an official navigational warning for awareness; mariners must use official NAVAREA broadcasts and their national MSI service.