Surveys

Survey operations 010001Z mar to 152359Z apr by M/V porquoi pas in: a. vicinity of trackline joining…

Tyrrhenian Sea · HYDROLANT 769/20

What this record establishes

Archived notice · 2020-03-21 02:30Z

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 III 314/20 291209Z FEB 20.. Issued 2020-02-29 18:21Z. 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
Tyrrhenian Sea. The parsed report position is 38.555, 12.380. It is a position in the source message, not a live location. Check the original wording for limits and qualifications.

Current notices and reporting history in the Tyrrhenian Sea →

Activity windows · 1 in this warning

opens (UTC)closes (UTC)locallength
2020-03-01 00:01Z2020-04-15 23:59Z—1103 h 58

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

issued
2020-02-29 18:21Z
status
Archived notice
self-cancels
2020-04-16 00:59Z
authority
NAVAREA III 314/20 291209Z FEB 20.
NAVAREA
NAVAREA III · named as the source of this relay
sea
Tyrrhenian Sea
position
38.555, 12.380
vessel
M/V PORQUOI PAS · 4 messages
source
NGA MSI broadcast-warn JSON (archive, frozen 2024-05) · first seen 2026-08-17 13:38Z

Original warning text

WESTERN MEDITERRANEAN SEA.
TYRRHENIAN SEA.
SICILY.
DNC 08, DNC 09.
1. SURVEY OPERATIONS 010001Z MAR TO 152359Z APR
   BY M/V PORQUOI PAS IN:
   A. VICINITY OF TRACKLINE JOINING
      39-13.6N 010-40.9E, 39-14.6N 011-02.5E,
      39-16.0N 011-25.6E, 39-17.2N 011-46.2E,
      39-18.5N 012-08.4E, 39-19.8N 012-30.0E,
      39-27.3N 012-45.9E, 39-35.1N 013-02.4E,
      39-45.9N 013-18.8E, 39-55.2N 013-33.2E.
   B. VICINITY OF TRACKLINE JOINING
      38-38.0N 010-37.2E, 38-29.1N 010-56.9E,
      38-23.3N 011-10.6E, 38-16.6N 011-23.9E,
      38-10.5N 011-36.6E, 38-05.9N 011-46.9E,
      38-01.1N 011-55.9E, 37-56.0N 012-10.1E,
      37-49.4N 011-57.5E, 37-42.9N 011-45.3E,
      37-36.0N 011-32.7E.
   C. VICINITY OF TRACKLINE JOINING
      38-10.6N 012-35.5E, 38-24.6N 012-34.7E,
      38-39.6N 012-33.3E, 38-53.4N 012-32.5E,
      39-06.8N 012-31.2E.
   D. VICINITY OF TRACKLINE JOINING
      36-02.1N 015-42.0E, 36-11.0N 016-01.4E,
      36-19.6N 016-19.8E.
   E. B-1, 39-11.3N 009-44.3E.
   F. B-2, 39-11.6N 010-00.3E.
   G. B-3, 39-12.6N 010-19.3E.
   H. C-1, 39-01.5N 009-45.1E.
   I. C-2, 38-55.4N 009-58.1E.
   J. C-3, 38-50.4N 010-09.8E.
   K. C-4, 38-44.0N 010-22.7E.
   L. D-1, 38-45.1N 008-51.6E.
   M. D-2, 38-34.8N 008-51.0E.
   N. D-3, 38-25.1N 008-50.4E.
   O. D-4, 38-14.7N 008-49.3E.
   WIDE BERTH REQUESTED.
2. CANCEL HYDROLANT 764/20.
3. CANCEL THIS MSG 160059Z APR 20.

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.
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.
Track line joining
Introduces a route through a series of positions — a cable route, a tow's track or a survey line.
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.
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.

All warning terms →

Collected reports in this area · survey operations

284 within 180 nm since 1999 · 0 in the last 12 months · 0 listed in force now

99
00
05
10
15
20
24

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

J
F
M
A
M
J
J
A
S
O
N
D

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

56 survey operations listed in force · see all

Record snapshot 2026-10-01 14:39Z; 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.