Passage Planning on ECDIS Flashcards
coverage, paper charts, scale, pick report, XTD, SMS, SD+SC (UKC), ETA,
Factors to consider when passage planning on ECDIS
(7)
- Availability of up-to-date ENCs and RNCs for the passage.
- Identify areas where ECDIS may need to be in RCDS mode and where paper charts may be required (MGN 285)
- If reusing a previous plan, recheck the route to confirm that it remains safe.
- Appropriate large scale ENC or RNC.
- Old or previous routes removed.
- Chart symbols (pick report) on ENCs to get detailed safety and nav info.
- Maximum acceptable cross track distance (XTD) to each leg of a route.
(- Complying with SMS and be appropriate size for the area) - Calculating safety depths and safety contours with UKC requirements in the SMS.
- Setting ETA information manually or using route planning
tools (e.g for tidal data and time dependent info) - Confirming correct information about the vessel’s characteristics.
Safety Depth
Calculation?
Value set by the mariner that is used by ECDIS to portray soundings as
black if they are equal to or shallower than the value and grey if they are deeper.
Safety depth=
Draught
+
UKC (including squat and a safety margin)
-
HoT
Safety Contour
A specific depth contour set by ECDIS.
It marks the boundary
between “safe-water” and shallow water
with an extra wide isoline and
is used to give an alarm if the ship, within a time specified by the mariner,
is going to cross the safety contour.
CATZOC
Define &
Specify (A1 > U)
Accuracy of data presented
A1. 6* s. +/- 5m
A2. 5* s. +/- 20m
B. 4* s. +/- 50m
C. 3* s. +/- 500m
D. 2* s. POOR
U. — UNASSESSED
Route Checking
(4)
- Passage plan should not be over/under detailed to avoid losing critical information.
- Visually inspected at optimum scale (1:1)
- ECDIS route scanning function.
-All items raised by scan to be checked. - Checked and approved by the Master.
Monitoring on ECDIS
Before Departure
(3)
- Passage plan is loaded on both the primary and backup ECDIS terminals
- The safety settings, particularly depth safety contours.
- Information from all sensors connected to the ECDIS are providing correct inputs.
Particular attention to
- GPS receiver
- Gyro compass
- Log
- Backup sensors
Monitoring on ECDIS
After Departure
(5)
- The capabilities and limitations of ENCs and RNCs
- Individual chart symbols (pick reports) on ENCs to get more detailed safety and navigational information
- Manage the amount of information displayed on an ECDIS terminal to avoid obscuring charted features and information, and the effects of information overload.
- Every opportunity should be taken to confirm the validity of a GNSS position with traditional fixing techniques.
- Looking ahead or using an offset view can improve situational awareness.
Other:
* Display of relative or true vectors.
* Over-reliance on ECDIS should be avoided, particularly if it prevents a proper lookout from being maintained.
5 Mandatory ECDIS Alarms
Cool Dudes Party All Day
- Crossing safety contour.
- Deviation from route.
- Positioning system failure.
- Approaching critical point.
- Different geodetic datum between chart and GNSS.
