Hazardous operations 260001Z apr to 130001Z may in area bound by 26-59.82S 046-22.87W, 26-59.82S 047-54.87W,…
South Atlantic Ocean · HYDROLANT 858/23
What this record establishes
Archived notice · 2023-05-13 01:01Z
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 131/23 210306Z APR 23.. Issued 2023-04-21 04:03Z. 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
- South 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.
Related notices and cancellation links
Current notices and reporting history in the South Atlantic Ocean →
Activity windows · 1 in this warning
| opens (UTC) | closes (UTC) | local | length |
|---|---|---|---|
| 2023-04-26 00:01Z | 2023-05-13 00:01Z | — | 408 h |
Parsed from the warning text; outside these windows the area is normally not active, but the warning stays in force until cancelled.
- issued
- 2023-04-21 04:03Z
- status
- Archived notice
- self-cancels
- 2023-05-13 01:01Z
- authority
- NAVAREA V 131/23 210306Z APR 23.
- NAVAREA
- NAVAREA V · named as the source of this relay
- sea
- South Atlantic Ocean
- position
- -27.874, -47.147
- source
- NGA MSI broadcast-warn JSON (archive, frozen 2024-05) · first seen 2026-08-17 13:38Z
Original warning text
WESTERN SOUTH ATLANTIC. BRAZIL. DNC 01. 1. HAZARDOUS OPERATIONS 260001Z APR TO 130001Z MAY IN AREA BOUND BY 26-59.82S 046-22.87W, 26-59.82S 047-54.87W, 28-45.07S 047-54.87W, 28-45.07S 046-22.68W. 2. CANCEL HYDROLANT 857/23. 3. CANCEL THIS MSG 130101Z MAY 23.
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.
- 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.
- CANCEL THIS MSG
- The warning's own expiry: a line telling the reader when the message cancels itself.
Collected reports in this area · military exercises
245 within 180 nm since 2003 · 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 100900Z to 110400Z aug in area bound by 28-29.50S 046-35.63W, 28-12.87S 047-04.53W,…2023-08-06
- Hazardous operations 160900Z to 292100Z jul in area bound by 27-59.52S 048-13.07W, 28-06.34S 048-01.90W,…2023-07-11
- Hazardous operations 260001Z apr to 130001Z may in area bound by 26-59.82S 046-22.87W, 26-59.82S 047-54.87W,…2023-04-21
- Hazardous operations 231900Z to 232100Z jan in area bound by 26-26.50S 047-55.50W, 26-42.00S 047-35.50W,…2023-01-21
- Hazardous operations 251000Z to 252000Z jan in area within 20 miles of 27-00.00S 044-00.00W2023-01-20
- Hazardous operations 242200Z to 250200Z jan in area bound by 27-28.00S 045-21.50W, 27-35.00S 045-36.00W,…2023-01-19
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 23:46Z; 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.