Surveys

Underwater operations 0800Z to 1800Z daily 28 sep thru 12 oct by M/V calypso and M/V commando b in 20-23.18S…

South Atlantic Ocean · HYDROLANT 1915/26

What this record establishes

Cancelled notice · 2026-09-28 16:45Z

This notice disappeared from the issuing source's in-force list. No explicit recovery or all-clear is established by that removal.

Source and dates: NGA MSI in-force warnings (DailyMem*.txt). Issued 2026-09-27 01:18Z. First collected 2026-09-28 19:32Z; last seen in collection 2026-09-28 23:02Z. Collection dates record ingestion, not a new incident or a fresh field observation.
Location covered: South Atlantic Ocean. The parsed report position is -20.386, -40.163. It is a position in the source message, not a live location. Check the original wording for limits and qualifications.

Current notices and reporting history in the South Atlantic Ocean →

Activity windows · 15 in this warning

opens (UTC)	closes (UTC)	local	length
2026-09-28 08:00Z	2026-09-28 18:00Z	—	10 h
2026-09-29 08:00Z	2026-09-29 18:00Z	—	10 h
2026-09-30 08:00Z	2026-09-30 18:00Z	—	10 h
2026-10-01 08:00Z	2026-10-01 18:00Z	—	10 h
2026-10-02 08:00Z	2026-10-02 18:00Z	—	10 h
2026-10-03 08:00Z	2026-10-03 18:00Z	—	10 h
2026-10-04 08:00Z	2026-10-04 18:00Z	—	10 h
2026-10-05 08:00Z	2026-10-05 18:00Z	—	10 h
… 7 more

Parsed from the warning text; outside these windows the area is normally not active, but the warning stays in force until cancelled.

issued: 2026-09-27 01:18Z
status: Cancelled notice
self-cancels: 2026-10-12 19:00Z
sea: South Atlantic Ocean
position: -20.386, -40.163
source: NGA MSI in-force warnings (DailyMem*.txt) · first seen 2026-09-28 19:32Z

Original warning text

SOUTH ATLANTIC.
BRAZIL.
1. UNDERWATER OPERATIONS 0800Z TO 1800Z
   DAILY 28 SEP THRU 12 OCT BY M/V CALYPSO
   AND M/V COMMANDO B IN 20-23.18S 040-09.77W.
   WIDE BERTH REQUESTED.
2. CANCEL THIS MSG 121900Z OCT 26.

Reading this warning

Underwater operations: Divers or remotely operated vehicles are working below a vessel that cannot easily move out of the way.
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

596 within 180 nm since 2000 · 57 in the last 12 months · 4 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

Underwater operations 0800Z to 1800Z daily 26 sep thru 10 oct by M/V comando b in 20-23.78S 040-09.43WSurveys · 0.7 nm
Foul ground until 06 dec 27 in area bound by 19-53.87S 039-59.68W, 19-54.15S 039-59.27W, 19-53.08S…Wrecks · 31.4 nm
Underwater operations 0800Z to 1800Z daily 26 sep thru 10 oct by M/V comando b in 19-51.63S 039-56.90WSurveys · 33.8 nm

Worldwide in the collected sources

54 survey operations listed in force · see all

Record snapshot 2026-09-28 23:08Z; 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.