Surveys

Survey operations 14 thru 16 apr by M/V polarcus alima towing 12 8100 meter long cables along tracklines…

South Atlantic Ocean · HYDROLANT 1196/17

What this record establishes

Archived notice · 2017-04-17 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 VI 243/17 141432Z APR 17.. Issued 2017-04-14 14:40Z. 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 Atlantic Ocean. The map shows the reported line or operation extent; it is not a vessel track. Check the original wording for limits and qualifications.

Related notices and cancellation links

Current notices and reporting history in the South Atlantic Ocean →

issued
2017-04-14 14:40Z
status
Archived notice
authority
NAVAREA VI 243/17 141432Z APR 17.
NAVAREA
NAVAREA VI · named as the source of this relay
sea
South Atlantic Ocean
position
-37.049, -52.738
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

WESTERN SOUTH ATLANTIC.
DNC 01, DNC 07.
1. SURVEY OPERATIONS 14 THRU 16 APR BY
   M/V POLARCUS ALIMA TOWING 12 8100 METER
   LONG CABLES ALONG TRACKLINES BETWEEN:
   A. 37-04.75S 051-03.82W AND 37-43.47S 053-15.95W.
   B. 37-43.47S 053-15.95W AND 35-36.60S 053-27.05W.
   SIX MILE BERTH REQUESTED.
2. CANCEL THIS MSG 17 APR 17.

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.
Track line joining
Introduces a route through a series of positions — a cable route, a tow's track or a survey line.
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

117 within 180 nm since 2000 · 0 in the last 12 months · 0 listed in force now

00
05
10
15
20
24

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

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

Worldwide in the collected sources

55 survey operations listed in force · see all

Record snapshot 2026-10-02 03:49Z; 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.