Surveys

Underwater operations in progress until further notice by M/V atlantic guardian along trackline between…

Bristol Channel · HYDROLANT 838/15

What this record establishes

Archived notice · 2015-04-13 20:58Z

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 434/15 091920Z APR 15.. Issued 2015-04-09 20:20Z. 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
Bristol Channel. The map shows the reported line or operation extent; it is not a vessel track. Check the original wording for limits and qualifications.

Current notices and reporting history in the Bristol Channel →

issued
2015-04-09 20:20Z
status
Archived notice
authority
WZ 434/15 091920Z APR 15.
issued by
WZ
sea
Bristol Channel
position
51.284, -3.798
vessel
M/V ATLANTIC GUARDIAN · 39 messages
source
NGA MSI broadcast-warn JSON (archive, frozen 2024-05) · first seen 2026-08-17 13:38Z

Original warning text

ENGLAND-SOUTHWEST COAST.
BRISTOL CHANNEL.
DNC 20.
1. UNDERWATER OPERATIONS IN PROGRESS UNTIL
   FURTHER NOTICE BY M/V ATLANTIC GUARDIAN
   ALONG TRACKLINE BETWEEN
   51-16.8N 003-42.8W AND 51-17.3N 003-53.0W.
   WIDE BERTH REQUESTED.
2. CANCEL HYDROLANT 832/15.

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.
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.

All warning terms →

Collected reports in this area · survey operations

752 within 180 nm since 1999 · 1 in the last 12 months · 0 listed in force now

99
00
05
10
15
20
25
26

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.

Month of issue in the collected archive

J
F
M
A
M
J
J
A
S
O
N
D

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 2026-10-03 13:49Z; 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.