Surveys

Survey operations in progress until 01 may by M/V polarcus alima towing 12 five mile long cables in area…

South China Sea · HYDROPAC 94/20

What this record establishes

Archived notice · 2020-06-01 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 7/20 080041Z JAN 20.. Issued 2020-01-08 00:50Z. 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: 2020-01-08 00:50Z
status: Archived notice
authority: NAVAREA XI 7/20 080041Z JAN 20.
NAVAREA: NAVAREA XI · named as the source of this relay
sea: South China Sea
position: 4.981, 111.422
vessel: M/V POLARCUS ALIMA · 115 messages
source: NGA MSI broadcast-warn JSON (archive, frozen 2024-05) · first seen 2026-08-17 13:38Z

Original warning text

SOUTH CHINA SEA.
MALAYSIA.
DNC 11.
1. SURVEY OPERATIONS IN PROGRESS UNTIL 01 MAY
   BY M/V POLARCUS ALIMA TOWING 12 FIVE
   MILE LONG CABLES IN AREA BOUND BY
   05-21N 110-58E, 04-41N 110-58E,
   04-41N 112-20E, 04-50N 112-00E,
   04-50N 111-50E, 05-00N 111-50E,
   05-00N 111-40E, 05-13N 111-40E,
   05-13N 111-44E, 05-21N 111-44E.
   WIDE BERTH REQUESTED.
2. CANCEL THIS MSG 01 JUN 20.

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.
Survey operations: A research or survey vessel is mapping the seabed or water column, often while towing equipment.
Towed array / streamer: Equipment towed a long way behind a vessel — sonar, a hydrophone cable, a sampling sled — invisible at the surface.
Tow / towing: A vessel towing another vessel, a barge or a structure — slow, hard to manoeuvre, and with a long line between.
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.

All warning terms →

Collected reports in this area · survey operations

13 within 180 nm since 2006 · 0 in the last 12 months · 0 listed in force now

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

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

No other collected notice is currently listed in force within this radius. This does not establish safe conditions.

Worldwide in the collected sources

56 survey operations listed in force · see all

Record snapshot 2026-10-01 13:18Z; 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.