Surveys

Underwater operations by M/V aegaeo: a. 240500Z to 240800Z and 271000Z to 271700Z nov in 35-43.86N 025-07.28E

Aegean Sea · HYDROLANT 3632/20

What this record establishes

Archived notice · 2020-11-28 08:00Z

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 III 1581/20 230127Z NOV 20.. Issued 2020-11-23 01:37Z. 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
Aegean Sea. The parsed report position is 36.223, 25.217. It is a position in the source message, not a live location. Check the original wording for limits and qualifications.

Current notices and reporting history in the Aegean Sea →

Activity windows · 5 in this warning

opens (UTC)closes (UTC)locallength
2020-11-24 05:00Z2020-11-24 08:00Z—3 h
2020-11-24 10:00Z2020-11-24 11:00Z—1 h
2020-11-27 07:00Z2020-11-27 08:00Z—1 h
2020-11-27 10:00Z2020-11-27 17:00Z—7 h
2020-11-28 06:00Z2020-11-28 07:00Z—1 h

Parsed from the warning text; outside these windows the area is normally not active, but the warning stays in force until cancelled.

issued
2020-11-23 01:37Z
status
Archived notice
self-cancels
2020-11-28 08:00Z
authority
NAVAREA III 1581/20 230127Z NOV 20.
NAVAREA
NAVAREA III · named as the source of this relay
sea
Aegean Sea
position
36.223, 25.217
vessel
M/V AEGAEO · 15 messages
source
NGA MSI broadcast-warn JSON (archive, frozen 2024-05) · first seen 2026-08-17 13:38Z

Original warning text

AEGEAN SEA.
DNC 09.
1. UNDERWATER OPERATIONS BY M/V AEGAEO:
   A. 240500Z TO 240800Z AND 271000Z TO
      271700Z NOV IN 35-43.86N 025-07.28E.
   B. 241000Z TO 241100Z AND 270700Z TO
      270800Z NOV IN 35-25.59N 025-04.35E.
   C. 280600Z TO 280700Z NOV IN
      37-30.72N 025-27.43E.
   WIDE BERTH REQUESTED.
2. CANCEL THIS MSG 280800Z NOV 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.
Underwater operations
Divers or remotely operated vehicles are working below a vessel that cannot easily move out of the way.
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.
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.

All warning terms →

Collected reports in this area · survey operations

198 within 180 nm since 2000 · 0 in the last 12 months · 0 listed in force now

00
05
10
15
20
22

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

Worldwide in the collected sources

56 survey operations listed in force · see all

Record snapshot 2026-10-01 13:03Z; 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.