Survey operations in progress until further notice by M/V ridley thomas in vicinity of trackline joining…
Celtic Sea · HYDROLANT 2466/20
What this record establishes
Archived notice · 2020-08-11 21:44Z
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) · WZ 828/20 081455Z AUG 20.. Issued 2020-08-08 15:31Z. 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
- Celtic Sea. 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
- Survey operations in progress until further notice by M/V ridley thomas in vicinity of trackline joining…cancelled by this notice
- Cancel HYDROLANT 2466/20 and this msg, operations suspendedlater cancellation notice
- issued
- 2020-08-08 15:31Z
- status
- Archived notice
- authority
- WZ 828/20 081455Z AUG 20.
- issued by
- WZ
- sea
- Celtic Sea
- position
- 50.817, -6.808
- vessel
- M/V RIDLEY THOMAS · 28 messages
- source
- NGA MSI broadcast-warn JSON (archive, frozen 2024-05) · first seen 2026-08-17 13:38Z
Original warning text
CELTIC SEA. ENGLAND. DNC 19. 1. SURVEY OPERATIONS IN PROGRESS UNTIL FURTHER NOTICE BY M/V RIDLEY THOMAS IN VICINITY OF TRACKLINE JOINING 50-48N 007-12W, 50-50N 006-25W. ONE MILE BERTH REQUESTED. 2. CANCEL HYDROLANT 2422/20.
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.
- Until further notice
- The operation or danger has no scheduled end; the warning stays in force until a later message cancels it.
- 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.
- 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.
Collected reports in this area · survey operations
711 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.
- Survey operations in progress until 31 oct by M/V ramform vanguard towing cables in area bound by 53-44.12N…2024-09-26
- Survey operations in progress until 20 jul by M/V celtic explorer in vicinity of trackline joining 47-30.00N…2023-06-14
- Survey operations 072201Z to 112159Z jun by vessel nanoplon in area within one mile of 48-20.67N 008-22.08W2023-06-06
- Underwater operations 180800Z to 192200Z nov by M/V willchallenge in vicinity of 50-19.0N 004-14.7W2022-11-17
- Survey operations in progress until 10 sep by M/V laperouse and M/V borda along trackline joining 48-27.48N…2022-09-01
- Underwater operations in progress until further notice by unmanned submersible ALR4 in vicinity of trackline…2022-06-10
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 10:07Z; 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.