BRIDGE - ECDIS

Question 1

What are the ECDIS safety settings?

Answer 1

Shallow contour - ships draft unnavigable water.

Safety contour - ships draft + UKC navigable water.

Safety depth - ships draft + UKC, anything below will be highlighted black as unnavigable.

Deep contour - ships draft x2 when squat may be experienced.

Question 2

What are the mandatory alarms of ecdis?

Answer 2

Crossing a safety contour.
Critical point approach.
Position fixing failure.
Deviation from route.
Change in geodetic datum.

Question 3

What are the limitations of ecdis?

Answer 3

Not worldwide coverage.
Single point failure = requires a power source and any system point failure ecdis is obsolete.
Training requirements can be time consuming.
Combined ecdis + paper increases workload.
Different systems = different interface.
Alarm fatigue.

Question 4

What are the limitations of ecdis?

Answer 4

Not worldwide coverage.
Single point failure = requires a power source and any system point failure ecdis is obsolete.
Training requirements can be time consuming.
Combined ecdis + paper increases workload.
Different systems = different interface.
Alarm fatigue.

Question 5

What are the IMO performance standards s52/57/58/63?

Answer 5

S52: Ensures visual presentation library is uniform (symbols lines colours.)
S57: How ENC data is constructed by the hydrographic office. .
S58: Validation checks to ensure ENC/ECDIS are compatible.
S63: Security, encryption from approved sources

Question 6

What would the position and depth accuracy A1 and A2 CATZOC tell you?

Answer 6

A1 / 6 stars

• position accuracy +/- 5m
• depth accurate 0.5 + 1% of depth
• example 10m depth = accurate to 0.6m

A2/ 5 stars

• position accuracy +/- 20m
• depth accuracy 1.00 + 2% depth
• example 10m depth = accurate to 1.2m

Question 7

What would the position and depth accuracy B, C, D and U CATZOC tell you?

Answer 7

B / 4 stars

• position accuracy +/- 50m
• depth accuracy 1.00 + 2% depth

C / 3 stars

• position accuracy +/- 500m
• depth accuracy 2.00 + 5% depth

D / 2 stars
- position and depth worse than c

U
- unassessed, does not mean that it hasn’t been surveyed. Just that the data hasn’t been reviewed.

Question 8

How will the categories of CATZOC been surveyed?

Answer 8

A1 - DGPS or 3 LOP and multibeam, channel or mechanical sweep

A2 - Modern survey echo sounder and sonar or mechanical sweep

B - Modern echo sounder but no sounder or mechanical sweep

C - When opportunity presents itself such as soundings on passage

D - No information

U - Hasn’t been assessed