Underwater operations 13 thru 23 jun by M/V yokosuka with submersible in area bound by 28-30N 138-20E,…
Philippine Sea · HYDROPAC 1741/21
What this record establishes
Archived notice · 2021-06-24 00:01Z
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 XI 193/21 121134Z JUN 21.. Issued 2021-06-12 12:00Z. 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
- Philippine 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 Philippine Sea →
- issued
- 2021-06-12 12:00Z
- status
- Archived notice
- authority
- NAVAREA XI 193/21 121134Z JUN 21.
- NAVAREA
- NAVAREA XI · named as the source of this relay
- sea
- Philippine Sea
- position
- 30.583, 139.667
- vessel
- M/V YOKOSUKA · 99 messages
- source
- NGA MSI broadcast-warn JSON (archive, frozen 2024-05) · first seen 2026-08-17 13:38Z
Original warning text
PHILIPPINE SEA. JAPAN. DNC 12. 1. UNDERWATER OPERATIONS 13 THRU 23 JUN BY M/V YOKOSUKA WITH SUBMERSIBLE IN AREA BOUND BY 28-30N 138-20E, 32-40N 138-20E, 32-40N 141-00E, 28-30N 141-00E. WIDE BERTH REQUESTED. 2. CANCEL THIS MSG 24 JUN 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.
- Underwater operations
- Divers or remotely operated vehicles are working below a vessel that cannot easily move out of the way.
- 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.
- 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.
Collected reports in this area · survey operations
45 within 180 nm since 1999 · 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.
- Underwater operations by submersible shinkai 6500 and M/V yokosuka: a. 05 thru 09 jun in areas bound by: a.…2025-06-04
- Underwater operations 04 thru 21 may by submersible shinkai 6500 and M/V yokosuka in area bound by 28-22.00N…2024-05-03
- Underwater operations 01 thru 07 mar by M/V yokosuka with submersible shinkai 6500 in areas bound by: a.…2024-02-29
- Underwater operations 24 thru 28 aug by M/V yokosuka with submersible shinkai 6500 in area bound by…2023-08-23
- Underwater operations 20 thru 27 sep by M/V shinkai 6500, mother ship, and yokosuka with subersible in area…2022-09-19
- Survey operations 28 oct thru 01 nov by M/V kaimei towing 7000 meter long cable in area bound by 33-00N…2019-10-27
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
- 180500Z issued at 190200Z sepVolcanic · 55 nm
- Discoloured water observed in vicinity of 31-26.4N 140-03.0E at 180545Z sepVolcanic · 55.1 nm
Worldwide in the collected sources
55 survey operations listed in force · see all
Record snapshot 2026-10-02 05:45Z; 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.