Survey operations in progress until 291000Z apr by M/V nho g sampaio and M/V nhib ten castelo in area bound…
South Atlantic Ocean · HYDROLANT 833/23
What this record establishes
Archived notice · 2023-04-29 11:00Z
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 COASTAL 203/23 172322Z APR 23.. Issued 2023-04-17 23:25Z. 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
- 2023-04-17 23:25Z
- status
- Archived notice
- self-cancels
- 2023-04-29 11:00Z
- authority
- NAVAREA V COASTAL 203/23 172322Z APR 23.
- NAVAREA
- NAVAREA V · named as the source of this relay
- issued by
- NAVAREA V COASTAL
- sea
- South Atlantic Ocean
- position
- -1.801, -43.858
- vessels
- M/V NHIB TEN CASTELO · 2 messagesM/V NHO G SAMPAIO · 2 messages
- source
- NGA MSI broadcast-warn JSON (archive, frozen 2024-05) · first seen 2026-08-17 13:38Z
Original warning text
WESTERN SOUTH ATLANTIC. BRAZIL. DNC 01. 1. SURVEY OPERATIONS IN PROGRESS UNTIL 291000Z APR BY M/V NHO G SAMPAIO AND M/V NHIB TEN CASTELO IN AREA BOUND BY 01-47.13S 043-54.63W, 01-47.13S 043-48.30W, 01-49.01S 043-48.30W, 01-49.01S 043-54.63W. WIDE BERTH REQUESTED. 2. CANCEL HYDROLANT 832/23. 3. CANCEL THIS MSG 291100Z APR 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.
- Survey operations
- A research or survey vessel is mapping the seabed or water column, often while towing equipment.
- 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.
- 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.
Collected reports in this area · survey operations
22 within 180 nm since 1999 · 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.
- Underwater operations in progress until 31 dec by M/V draga volzee in area bound by 02-25.00S 042-18.00W,…2023-07-01
- Survey operations 13 jun thru 03 jul by M/V marion dufresne along trackline joining 06-39.38N 052-04.99W,…2023-06-09
- Survey operations 13 jun thru 03 jul by M/V marion dufresne along trackline joining 06-39.38N 052-04.99W,…2023-06-09
- Survey operations in progress until 291000Z apr by M/V nho g sampaio and M/V nhib ten castelo in area bound…2023-04-17
- Survey operations in progress until 181500Z oct by M/V napoc iguatemi in area bound by 01-47.13S 043-48.30W,…2022-10-09
- Hydrographic survey in progress until 09 sep by M/V garnier sampaio in area bound by 00-32.7N 045-55.0W,…2014-08-12
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
Worldwide in the collected sources
56 survey operations listed in force · see all
Record snapshot 2026-10-03 15:08Z; 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.