Sierra leone
North Atlantic Ocean · HYDROLANT 574/18
What this record establishes
Archived notice · 2018-03-28 15:43Z
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 90/18 161620Z FEB 18.. Issued 2018-02-16 16:21Z. 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
- North Atlantic Ocean. The map shows the reported line or operation extent; it is not a vessel track. Check the original wording for limits and qualifications.
Related notices and cancellation links
- Sierra leonelater cancellation notice
Current notices and reporting history in the North Atlantic Ocean →
Activity windows · 1 in this warning
| opens (UTC) | closes (UTC) | local | length |
|---|---|---|---|
| 2018-02-19 12:00Z | 2018-04-03 23:59Z | — | 1043 h 59 |
Parsed from the warning text; outside these windows the area is normally not active, but the warning stays in force until cancelled.
- issued
- 2018-02-16 16:21Z
- status
- Archived notice
- self-cancels
- 2018-04-04 00:59Z
- authority
- NAVAREA II 90/18 161620Z FEB 18.
- NAVAREA
- NAVAREA II · named as the source of this relay
- sea
- North Atlantic Ocean
- position
- 4.990, -10.002
- vessel
- M/V REBECCA · 100 messages
- source
- NGA MSI broadcast-warn JSON (archive, frozen 2024-05) · first seen 2026-08-17 13:38Z
Original warning text
EASTERN NORTH ATLANTIC. GULF OF GUINEA. COTE DIVOIRE. LIBERIA. SIERRA LEONE. DNC 01. 1. CABLE OPERATIONS 191200Z FEB TO 032359Z APR BY M/V REBECCA IN VICINITY OF TRACKLINE JOINING 04-19.1N 004-27.2W, 03-59.9N 006-10.4W, 03-48.5N 007-04.9W, 03-55.2N 009-36.0W, 04-57.3N 011-14.2W, 05-11.2N 011-33.0W, 06-59.2N 013-59.0W, 07-12.4N 014-19.0W, 07-42.3N 015-02.9W. WIDE BERTH REQUESTED. 2. CANCEL THIS MSG 040059Z APR 18.
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.
- Cable operations
- A ship is laying, burying or repairing a submarine cable, usually along a stated route.
- 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.
- Track line joining
- Introduces a route through a series of positions — a cable route, a tow's track or a survey line.
- 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.
Collected reports in this area · cable & pipeline work
8 within 180 nm since 2010 · 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.
- Cable operations in progress until 112300Z sep by cableship ile d'aix along tracklines joining: a. 02-17.00N…2023-09-06
- Cable operations 120001Z aug to 062300Z sep by cableship ile d'aix along tracklines joining: a. 02-17.00N…2023-08-11
- Cable operations by cableship ile d'aix: a. 09 thru 11 aug along trackline joining 02-17.00N 003-44.00W,…2023-08-06
- Seismic survey in progress until further notice by M/V polarcus asima towing 12 1000 meter long cables in…2013-03-04
- Seismic survey in progress until 02 feb M/V polarcus asima towing 12 10000 meter long cables in area bound…2013-01-19
- Cable operations in progress until 20 nov by cableship ile de sein along trackline joining 06-18.03N…2011-11-03
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
22 cable & pipeline work listed in force · see all
Record snapshot 2026-09-25 07:13Z; 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.