Survey operations in progress until 05 nov by M/V nho cruzeiro do sul towing two 500 meter long cables in…
South Atlantic Ocean · HYDROLANT 2557/21
What this record establishes
Archived notice · 2021-11-06 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 V 476/21 171419Z OCT 21.. Issued 2021-10-17 14:24Z. 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
- 2021-10-17 14:24Z
- status
- Archived notice
- authority
- NAVAREA V 476/21 171419Z OCT 21.
- NAVAREA
- NAVAREA V · named as the source of this relay
- sea
- South Atlantic Ocean
- position
- -21.440, -34.724
- vessel
- M/V NHO CRUZEIRO DO SUL · 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-SOUTHEAST COAST. DNC 01. 1. SURVEY OPERATIONS IN PROGRESS UNTIL 05 NOV BY M/V NHO CRUZEIRO DO SUL TOWING TWO 500 METER LONG CABLES IN AREA BOUND BY 23-07.87S 043-05.98W, 22-56.08S 039-58.23W, 22-35.73S 037-37.09W, 22-21.86S 035-55.63W, 21-50.23S 034-48.66W, 22-05.96S 033-45.07W, 22-39.76S 033-58.05W, 23-04.56S 033-10.66W, 22-51.75S 032-39.27W, 22-05.21S 032-20.54W, 20-42.52S 031-48.52W, 20-12.14S 029-15.40W, 19-52.09S 031-35.12W, 20-02.06S 033-28.23W, 20-52.12S 033-38.47W, 20-06.04S 034-38.98W, 20-23.59S 035-31.90W, 21-14.01S 037-05.32W, 22-33.12S 039-28.49W, 22-49.99S 040-43.65W. WIDE BERTH REQUESTED. 2. CANCEL HYDROLANT 2464/21. 3. CANCEL THIS MSG 06 NOV 21.
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.
- 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
9 within 180 nm since 2000 · 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.
- Survey operations 20 thru 25 apr by M/V oceanic sirius towing 12 11112 meter cables in area bound by…2021-04-20
- Survey operations 27 may thru 01 jun by M/V ramform titan towing 14 10000 meter long cables in area bound by…2020-05-26
- Hydrographic survey 16 thru 23 jul by M/V ocean endeavour in area bound by 23-59.87S 041-19.42W, 20-16.51S…2016-07-15
- Oceanographic operations 03 thru 14 nov by M/V antares in area bound by 20-40S 040-00W, 20-40S 029-25W,…2003-11-01
- Oceanographic operations 19 thru 31 oct by M/V antares in area bound by 20-40S 040-00W, 21-30S 040-15W,…2003-10-18
- Oceanographic operations 05 thru 15 oct by M/V antares in area bound by 23-10S 042-00W, 24-45S 029-10W,…2003-09-30
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
- 18.3 meter depth reported in 20-35.71S 034-46.07WWrecks · 50.8 nm
Worldwide in the collected sources
56 survey operations listed in force · see all
Record snapshot 2026-10-03 07:15Z; 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.