Exercises

Hazardous operations 201315Z to 201615Z, 210300Z to 210645Z, 211315Z to 211615Z, 220300Z to 220645Z and…

Aegean Sea · HYDROLANT 1074/21

What this record establishes

Archived notice · 2021-04-22 18:00Z

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 402/21 191200Z APR 21.. Issued 2021-04-19 09:42Z. 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 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 Aegean Sea →

Activity windows · 5 in this warning

opens (UTC)	closes (UTC)	local	length
2021-04-20 13:15Z	2021-04-20 16:15Z	—	3 h
2021-04-21 03:00Z	2021-04-21 06:45Z	—	3 h 45
2021-04-21 13:15Z	2021-04-21 16:15Z	—	3 h
2021-04-22 03:00Z	2021-04-22 06:45Z	—	3 h 45
2021-04-22 14:10Z	2021-04-22 17:00Z	—	2 h 50

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

issued: 2021-04-19 09:42Z
status: Archived notice
self-cancels: 2021-04-22 18:00Z
authority: NAVAREA III 402/21 191200Z APR 21.
NAVAREA: NAVAREA III · named as the source of this relay
sea: Aegean Sea
position: 36.500, 23.917
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. HAZARDOUS OPERATIONS 201315Z TO 201615Z,
   210300Z TO 210645Z, 211315Z TO 211615Z,
   220300Z TO 220645Z AND 221410Z TO 221700Z APR
   IN AREA BOUND BY
   36-40N 023-40E, 36-40N 024-10E,
   36-20N 024-10E, 36-20N 023-40E.
2. CANCEL THIS MSG 221800Z APR 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.
Hazardous operations: NGA's heading for activities that make an area dangerous — most often rocket launches, space debris and weapons firings, and some open-ended danger areas.
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.
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.
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 · military exercises

953 within 180 nm since 1998 · 1 in the last 12 months · 1 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.

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

Missile operations 0530Z to sunset daily every wednesday thru saturday until 14 jun and 16 seb thru 31 dec…Missiles · 78.9 nm
Hazardous operations sunrise to sunset daily until 14 jun and 16 sep thru 31 dec in area bound by 38-16.00N…Exercises · 107 nm

Worldwide in the collected sources

9 military exercises listed in force · see all

Record snapshot 2026-10-03 16:20Z; source collection times vary.

Exercises

Gunnery, firing and naval exercise areas. All current military exercises →

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.