ECDIS Flashcards
Purpose of ECDIS? (3 factors)
- Reduce OOW workload (passage planning, updates, route monitoring)
- Contribute to safe navigation
- Pre warn of something dangerous or something that might lead to something dangerous
Difference between ECDIS & ECS?
ECDIS has high standards from IMO, IEC and IHO in terms of hardware, software, charts and back up power arrangements, can be used as paperless bridge under solas chapter 5 and Electronic Chart System is any system that doesn’t reach those requirements
What do you need to have an approved ECDIS system for a paperless bridge onboard? (9)
Type approved, installed by approved contractors, will state in form E
1. Two fully independent ECDIS systems with individual reserve back up power and connected to emergency power,
2. Need to be able to display both raster and vector charts,
3. They must have separate position input,
4. Must have heading (gyro) & speed (log) inputs
5. Need to display AIS, ARPA & radar information,
6. Need to be corrected on a weekly basis or manually corrected,
7. Operator must be able to overlay information,
8. Hardware must be approved by IEC,
9. ECDIS must display an SENC
Raster chart definition?
High quality scan of an existing paper chart
Advantages Raster charts? (4 factors)
- Global coverage
- Familiar
- Fully approved
- Cheap
Disadvantages Raster charts? (9)
- Large file sizes
- Cluttered when zoomed out
- Different scales
- Not scalable
- Not intelligent (grounding alarms)
- Not seamless (has boundaries)
- Cant be used as a primary mean of navigation (need to get paper charts for that part of the voyage)
- Navigational risk assessment of the part of the voyage where the raster chart is used
- Can only be used where SENCs aren’t available
Vector chart definition?
Multi layered database of information
Advantages vector charts? (7)
- Intelligent (can be interrogated)
- Apparently seamless
- Scalable with no distortion when zooming
- Information layers may be added or removed
- Alarms & indications
- Ability to monitor own ship’s route
- Small file sizes when updating
Disadvantages vector charts? (5)
- Expensive and timely to produce,
- Same survey data as paper,
- Unfamiliar symbols,
- Operator error
- High chance of a false sense of security
Display options? (4)
Display base, standard display, all display & custom display
Whats shown on Display base? (7)
- Land,
- Own ships safety contour
- Scale
- Range,
- North arrow
- Drying heights
- Isolated dangers within the safety contour
Whats shown on Standard display?
Everything in Display base plus
1. Bouys
2. TSS
3. Special areas
4. Ferry routes
What is CATZOC?
A quality scale of position and depth (A1, A2, B, C, D, U)
List 5 alarms that ECDIS will sound?
Audible & visible, which require immediate attention
1. Deviation from route
2. Crossing safety contour
3. Position system failure
4. Approaching critical point
5. Entering non ENC area (Raster chart area)
6. Different Geodetic datum
List 5 indications ECDIS will show?
Visual or audible, can lead to dangerous situation in future
1. Over scaling
2. Under scaling
3. Route planning over safety contour
4. Route planning over special area
5. System test failure
What is needed of the operator? ECDIS
- Verify inputs
- Verify overlays
- Verify position
- Route planning
- Alarms
Advantages of ECDIS? (9)
- Ships position continuously displayed
- Improved spatial awareness for the watch keeper
- Multiple displays at conning position/ nav station/ lookout
- Information overlays to increase situational awareness
- Quick and easy route planning
- Automatic log book recording
- Quick and easy chart corrections
- Professional chart correction
- Alarms
Disadvantages of ECDIS?
- Over-reliance on ECDIS
- Information overload
- Big reliance of GPS - possible lack of accuracy
- False sense of security
- Specialist training
- Alarm apathy
- Expensive
How do you check your ECDIS is up to date?
I can check if my ECDIS has the correct S-52 Presentation library 4.0
I would download the performance standards as per IHO & IEC
Then I would go to chart #1 and zooming in to correct lat and long, making sure it matches the performance standards
Can you use the latest disc?
Yes, the discs are cumulative and the latest one will have all the previous corrections
What would the symbol look like if the ECDIS can’t display something correctly?
It would be a magenta question mark
Difference between safety contour and safety depth?
Safety contour is a depth contour set by the ECDIS and it marks the boundary between safe water and shallow water by and extra wide isoline and it gives an alarm
Safety depth gives a value set by the mariner and is used by the ECDIS to portray soundings in a black colour.
What happens if you lose gps?
The ECDIS will go into DR mode
How do you know your ECDIS is approved?
Type approval certificate
Connection to correct feeds (power, emergency power, speed log, gyro receiver, gps)
Back-up arrangements (another ECDIS or paper charts)
Being maintained with IHO standards
Charts are updated
What is AVCS?
Admiralty Vector Chart Service
Which vessels must have ECDIS?
Passenger ships <500GT
Cargo ships <3000GT
Engaged on international voyages
Which part of SOLAS states the carriage requirements for ECDIS?
SOLAS chapter V, Regulation 19
How would you set up your deep contour?
Draught x2
How do we update our ECDIS charts?
CD, DVD, Download list or Manual update. Read the README file before
Update one ECDIS at a time in case of corruption
Print a system report (certificate) and log in NP133C (ENC Maintenance record)
What presentation library is there now?
S-52 4.0
S-52?
Display standard for ENCs
S-57?
Digital data transfer exchange
S-63?
Digital data encryption
S-61?
Raster chart standards
How do we know our ECDIS charts are not up to date?
View the chart catalogue and check that the names of all required charts appear in green. The names of charts which are not up-to-date appear in orange.
