Survey operations in progress until 01 jul by M/V polarcus adira towing 12 six mile long cables in area…
Gulf of Guinea · HYDROLANT 983/20
What this record establishes
Archived notice · 2020-03-24 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 II 85/20 150858Z MAR 20.. Issued 2020-03-15 11:29Z. 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
- Gulf of Guinea. 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
- Cable operations 120001Z dec until further notice by M/V polarcus adira towing 12 six mile long cables in…cancelled by this notice
- Cancel HYDROLANT 983/20 and this msglater cancellation notice
Current notices and reporting history in the Gulf of Guinea →
- issued
- 2020-03-15 11:29Z
- status
- Archived notice
- authority
- NAVAREA II 85/20 150858Z MAR 20.
- NAVAREA
- NAVAREA II · named as the source of this relay
- sea
- Gulf of Guinea
- position
- 0.842, 7.125
- vessel
- M/V POLARCUS ADIRA · 68 messages
- source
- NGA MSI broadcast-warn JSON (archive, frozen 2024-05) · first seen 2026-08-17 13:38Z
Original warning text
GULF OF GUINEA. SAO TOME AND PRINCIPE. DNC 01. 1. SURVEY OPERATIONS IN PROGRESS UNTIL 01 JUL BY M/V POLARCUS ADIRA TOWING 12 SIX MILE LONG CABLES IN AREA BOUND BY 01-15N 006-22E, 01-15N 007-53E, 00-26N 007-53E, 00-26N 006-22E. SEVEN MILE BERTH REQUESTED. 2. CANCEL HYDROLANT 3775/19. 3. CANCEL THIS MSG 02 JUL 20.
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
26 within 180 nm since 2003 · 2 in the last 12 months · 1 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.
- Last known positions of mobile oil rigs and drill ships at 040430 UTC sep 262026-09-04
- Last known positions of mobile oil rigs and drill ships at 091630 UTC aug 262026-08-09
- Survey operations 27 mar thru 15 may by M/V rem saltire and M/V bgp dragon in area bound by 03-06.80N…2024-03-24
- Survey operations 12 feb thru 26 mar by M/V bgp dragon and M/V rem saltire in area bound by 03-17.54N…2024-02-09
- Survey operations 10 dec thru 15 jan 24 by M/V apollo, M/V vanguard and M/V thor freyja in areas bound by:…2023-12-07
- Survey operations 17 nov thru 09 dec by M/V vanguard and M/V thor freyja in area bound by 03-14.94N…2023-11-14
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
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 02:55Z; 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.