Exercises

Hazardous operations

North Atlantic Ocean · HYDROLANT 3404/16

What this record establishes

Archived notice · 2017-01-20 21:30Z

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 V 356/16 162304Z DEC 16.. Issued 2016-12-16 23:55Z. 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: North Atlantic Ocean. 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 North Atlantic Ocean →

Activity windows · 31 in this warning

opens (UTC)	closes (UTC)	local	length
2016-12-21 19:30Z	2016-12-21 20:30Z	—	1 h
2016-12-22 19:30Z	2016-12-22 20:30Z	—	1 h
2016-12-23 19:30Z	2016-12-23 20:30Z	—	1 h
2016-12-24 19:30Z	2016-12-24 20:30Z	—	1 h
2016-12-25 19:30Z	2016-12-25 20:30Z	—	1 h
2016-12-26 19:30Z	2016-12-26 20:30Z	—	1 h
2016-12-27 19:30Z	2016-12-27 20:30Z	—	1 h
2016-12-28 19:30Z	2016-12-28 20:30Z	—	1 h
… 23 more

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

issued: 2016-12-16 23:55Z
status: Archived notice
self-cancels: 2017-01-20 21:30Z
authority: NAVAREA V 356/16 162304Z DEC 16.
NAVAREA: NAVAREA V · named as the source of this relay
sea: North Atlantic Ocean
position: 4.980, -47.327
source: NGA MSI broadcast-warn JSON (archive, frozen 2024-05) · first seen 2026-08-17 13:38Z

Original warning text

WESTERN NORTH ATLANTIC.
BRAZIL-NORTH COAST.
HAZARDOUS OPERATIONS.
DNC 01.
1. HAZARDOUS OPERATIONS 1930Z TO 2030Z
   DAILY 21 DEC THRU 20 JAN 17
   IN AREAS BOUND BY:
   A. 05-15N 047-27W, 04-44N 047-28W,
      04-46N 048-27W, 05-18N 048-25W.
   B. 05-02N 045-47W, 04-46N 045-48W,
      04-51N 047-32W, 05-08N 047-31W.
2. CANCEL THIS MSG 202130Z JAN 17.

Reading this warning

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.
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.
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.
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.

All warning terms →

Collected reports in this area · military exercises

58 within 180 nm since 2000 · 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.

Hazardous operations 142025Z feb to 140005Z mar in areas bound by: a. 05-16N 047-26W, 04-44N 047-27W, 04-47N…2017-02-11
Hazardous operations 140300Z to 150300Z feb in area bound by 05-16N 047-26W, 04-44N 047-27W, 04-47N 048-26W,…2017-02-09
Hazardous operations2017-01-22
Hazardous operations2017-01-22
Hazardous operations2016-12-15
Hazardous operations2016-09-30

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

17 military exercises listed in force · see all

Record snapshot 2026-09-24 22:59Z; 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.