Survey operations with submersible: a. 08 thru 15 apr in area within three miles of 36-17.82N 015-58.71E
Ionian Sea · HYDROLANT 926/21
What this record establishes
Archived notice · 2021-04-22 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 III 314/21 061200Z APR 21.. Issued 2021-04-05 12:59Z. 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
- Ionian 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.
- issued
- 2021-04-05 12:59Z
- status
- Archived notice
- authority
- NAVAREA III 314/21 061200Z APR 21.
- NAVAREA
- NAVAREA III · named as the source of this relay
- sea
- Ionian Sea
- position
- 37.503, 15.384
- source
- NGA MSI broadcast-warn JSON (archive, frozen 2024-05) · first seen 2026-08-17 13:38Z
Original warning text
EASTERN MEDITERRANEAN SEA.
IONIAN SEA.
SICILY.
DNC 09.
1. SURVEY OPERATIONS WITH SUBMERSIBLE:
A. 08 THRU 15 APR IN AREA WITHIN THREE MILES
OF 36-17.82N 015-58.71E.
B. 17 THRU 21 APR IN AREA WITHIN THREE MILES
OF 37-30.01N 015-23.03E.
WIDE BERTH REQUESTED.
2. CANCEL THIS MSG 22 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.
- Survey operations
- A research or survey vessel is mapping the seabed or water column, often while towing equipment.
- Within a radius of
- A circular area — every position within a stated distance of a point.
- 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
239 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 M/V handin tide with submersible: a. 01 thru 05 jun in area within ten miles of…2022-05-27
- Survey operations 13 thru 21 feb by M/V havila phoenix with submersible along trackline joining 35-56.56N…2022-02-11
- Underwater operations by M/V handin tide: a. 01 thru 05 sep in area within ten miles of 37-30-00N 015-23-02E2021-08-30
- Underwater operations 15 thru 19 jul notice by M/V hercules in area bound by 36-19.50N 014-53.28E,…2021-07-14
- Survey operations in progress until 22 jul in areas bound by: a. 35-54.54N 012-48.96E, 35-54.54N 012-55.38E,…2021-06-25
- Survey operations in progress until 15 jul by M/V astrea in area bound by 37-25.7N 012-35.8E, 37-25.7N…2021-06-08
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
Worldwide in the collected sources
56 survey operations listed in force · see all
Record snapshot 2026-10-03 23:27Z; 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.