Cable ops

Seismic survey in progress until 250259Z may by M/V western neptune towing 12 3.5 mile long cables in area…

South Atlantic Ocean · HYDROLANT 861/11

What this record establishes

Archived notice · 2011-05-25 03:59Z

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 V 281/11 22 MAY 11 - NAVAREA II 154/11 220815Z MAY 11.. Issued 2011-05-22 09:42Z. 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 an area described by the warning; the listed coordinate is its representative center. Check the original wording for limits and qualifications.

Related notices and cancellation links

Current notices and reporting history in the South Atlantic Ocean →

issued
2011-05-22 09:42Z
status
Archived notice
self-cancels
2011-05-25 03:59Z
authority
NAVAREA V 281/11 22 MAY 11 - NAVAREA II 154/11 220815Z MAY 11.
NAVAREA
NAVAREA V · named as the source of this relay
sea
South Atlantic Ocean
position
-22.462, -40.487
vessel
M/V WESTERN NEPTUNE · 226 messages
source
NGA MSI broadcast-warn JSON (archive, frozen 2024-05) · first seen 2026-08-17 13:38Z

Original warning text

BRAZIL-SOUTHEAST COAST.
1. SEISMIC SURVEY IN PROGRESS UNTIL 250259Z MAY BY
   M/V WESTERN NEPTUNE TOWING 12 3.5 MILE LONG
   CABLES IN AREA BOUND BY
   22-07.8S 040-35.0W, 22-23.5S 040-07.0W,
   22-48.0S 040-24.0W, 22-31.5S 040-51.2W.
   SIX MILE BERTH REQUESTED.
2. CANCEL HYDROLANT 825/11(57), OPERATIONS COMPLETED.
3. CANCEL HYDROLANT 835/11.
4. CANCEL THIS MSG 250359Z MAY.

Reading this warning

Seismic survey
A survey that maps the rock beneath the seabed with sound pulses from air guns, recorded on streamers kilometres long.
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.
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.
Cancellation reference
A line that cancels an earlier warning by its number, such as CANCEL HYDROLANT 1085/12.
HYDROLANT
The U.S. long-range warning series for Atlantic waters outside NAVAREA IV, including the eastern Atlantic, the Mediterranean and adjoining seas.
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 · cable & pipeline work

1861 within 180 nm since 1998 · 0 in the last 12 months · 0 listed in force now

98
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

Worldwide in the collected sources

23 cable & pipeline work listed in force · see all

Record snapshot 2026-10-03 01:17Z; source collection times vary.

Cable ops

Cable laying, pipeline and seismic operations. All current cable & pipeline work →

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.