Underwater operations 22 sep thru 16 oct by M/V dalla porta in area bound by 37-34N 011-14E, 37-23N 011-36E,…
Mediterranean Sea - Western Basin · HYDROLANT 2366/21
What this record establishes
Archived notice · 2021-10-17 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 III 708/21 201335Z SEP 21.. Issued 2021-09-20 14:17Z. 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
- Mediterranean Sea - Western Basin. The map shows an area described by the warning; the listed coordinate is its representative center. Check the original wording for limits and qualifications.
Current notices and reporting history in the Mediterranean Sea - Western Basin →
- issued
- 2021-09-20 14:17Z
- status
- Archived notice
- authority
- NAVAREA III 708/21 201335Z SEP 21.
- NAVAREA
- NAVAREA III · named as the source of this relay
- sea
- Mediterranean Sea - Western Basin
- position
- 37.341, 11.422
- vessel
- M/V DALLA PORTA · 13 messages
- source
- NGA MSI broadcast-warn JSON (archive, frozen 2024-05) · first seen 2026-08-17 13:38Z
Original warning text
STRAIT OF SICILY. TUNISIA. DNC 08. 1. UNDERWATER OPERATIONS 22 SEP THRU 16 OCT BY M/V DALLA PORTA IN AREA BOUND BY 37-34N 011-14E, 37-23N 011-36E, 37-10N 011-36E, 37-13N 011-18E. ONE MILE BERTH REQUESTED. 2. CANCEL THIS MSG 17 OCT 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.
- Underwater operations
- Divers or remotely operated vehicles are working below a vessel that cannot easily move out of the way.
- 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.
- 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
261 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 further notice by M/V joides resolution in: a. 40-11.03N 012-42.49E2024-02-16
- Survey operations 10 apr thru 10 may by M/V dalla porta in: a. 37-23.06N 011-35.59E2022-04-08
- Survey operations 13 thru 21 feb by M/V havila phoenix with submersible along trackline joining 35-56.56N…2022-02-11
- Survey operations in progress until 12 mar 22 by M/V artabro in area bound by 36-46.3N 011-01.8E, 37-01.5N…2021-10-30
- Survey operations in progress until 12 mar 22 by M/V viccica in area bound by 36-48.5N 011-02.9E, 36-46.8N…2021-10-30
- Survey operations in progress until 01 nov by M/V artabro in area bound by 36-47.4N 011-04.3E, 37-14.2N…2021-10-25
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
56 survey operations listed in force · see all
Record snapshot 2026-10-01 21:45Z; 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.