Navigation Reading Heading

3). Heading

• By heading is understood the direction in which the vessel is pointing.
• The angle between the fore-and aft line of the vessel. and True North is expressed in degrees
• Heading constantly changes due to influences of sea and wind and Steering errors.

 

 

• Course
• The intended sailing direction is expressed in degrees and is the direction in which the vessel is steered

 

 

 

 

Rhumb line A course line whereby all the angles made by the course line and the meridians are equal is called a rhumb line, or loxodrome.

 

 

 

 

Track For a safe passage, for instance when clearing a dangerous wreck, the course lines along which a navigator intends to proceed form the track.

 

 

If no allowances are made for a wind and current the vessel will follow a line called course over ground If allowances are made for wind and current the vessel will follow a line called course made good

 

 

4) Position

Oral Practice:

• every number must be pronounced separately.
• “point” is pronounced as “decimal” (2.5 = two – decimal – five)
• be fluent in your pronunciation; every mistake, however little, must be corrected by the phrase “mistake…..correction”, followed by the correct position.

• 51 DEGR. 29 MIN. N / 047 DEGR. 53 MIN E.
• 134 DEGR. FROM BUOY NHR-SE, DISTANCE 0.6 MILES
• 159 DEGR. FROM FALLS LIGHT, DISTANCE 2.4 MILES.
• 49 DEGR. 8 MIN N / 013 DEGR. 5 MIN. W
• 178 DEGR. FROM ROYAL SOVEREIGN LIGHTHOUSE, DISTANCE 4.1 MILES.
• 250 DEGR. FROM BUOY CA 4, DISTANCE 1.2 MILE.
• 68 DEGR. 27 MIN. N / 039 DEGR. 53 MIN. E
• 025 DEGR. FROM ALICE BUOY, DISTANCE 2.5 MILES.
• 46 DEGR. 29 MIN. S / 018 DEGR. 53 MIN. E
• 158 DEGR. FROM THE BASSURELLE, DISTANCE 1.5 MILE5)

5). Position

Cross bearing and cock hat

– Fill in: ………

 

• X = conspicuous object
• a = cocked hat
• b = bearing line
• c = intersection
• d = check line

 

 

– Finish the sentences

• A “conspic” is an object on land or at sea that is mentioned and described in the pilot book.
• The ship’s position is in or at the cocked hat
• A triangle of 2 bearing-lines and 1 check line is formed, because the vessel is proceeding

Running fix

– Fill in: ………

• X = conspicuous object
• a = course line
• b = distance
• c = line that runs parallel to the first bearing line
• d = position

A running fix is made when there is only one conspicuous object available
The second bearing is taken at 16.52 hrs.; Log-reading: distance travelled is 847 miles.
The difference between the first and the second bearing is 2 miles.
The distance is measured from the chart scale at the side of the nautical chart and transferred to the course line with the aid of chart dividers

The position of the ship is at the intersection of the line that
runs parallel to the first bearing line and the second bearing line

6) Order of events (“Running Fix”)

Indicate the order of events by filling in A, B, C, etc.

• A – Measure mileage by means of log-reading.
• B – Determine the position of the Conspic.
• C – Proceed on ground course
• D – Take first bearing
• E – Take second bearing
• F – Determine the intersection (ship’s posn.) on the parallel line with the second bearing line.
• G – Transfer mileage to course line
• H – Determine the angle between the two bearing lines (>30 degr.)
• I – Draw a line parallel with the 1st bearing line through transfer-point.

7) Direction

Match the numbers (“expressions”) with the letters (“directions”)

1. before the starboard beam
2. on the port bow
3. on the port beam
4. on the starboard bow
5. astern
6. starboard
7. port
8. ahead
9. on the stem
10. on the port quarter
11. on the starboard beam
12. on the starboard quarter
13. abaft the starboard beam
14. on the stern
15. abaft the port beam
16. before the port beam

8). Reports on groundings

1. “It was the first time that we sailed these waters, which are renowned to be dangerous, especially if you do not know your way around. And indeed: after 2 miles we went aground!”.
2. “When we enter the fairway, our vessel was drawing 21 metres. Our first mate had miscalculated our UKC and thought it would suffice to pass through the channel – it didn’t!”
3. “We had been warned about these waters and soon found out that the depths indicated in the chart where by no means to be trusted: we went aground”.
4. “In a fierce gale we were hit by an enormous wave that put us off course in the narrow fairway. We could not avoid the shoals and we went aground”.
5. “We had sailed these waters many times and knew the settings of currents and times of tides by heart. Unfortunately the Low Slack period lasted longer than usual, and grounding could not be avoided”.
6. “Due to illness of the ABS one of the ordinary sailors was pointed helmsman. Unfortunately his English was to poor to execute the OOW’s helmorders properly. We hit a sandbank”.
7. “A storm in the area had resulted in the forming of a shoal patch, on which we went aground”.
8. “We went aground because we had not been able to determine the depth of the fairway due to malfunction”.
9. “We went aground because the conning officer had mis-interpreted data on the Radar”.
10. “To reduce expenses, the documents on the bridge had not been updated. Therefore we did not have the correct data to proceed safely through these waters.This has resulted in the grounding of our vessel”.

Causes of groundings

• A – Steering error
• F – Data misread
• B – Tide below prediction
• G – Vessel is of deep draft
• C – Charted depth unreliable
• H – Echo sounder not functioning
• D – Obsolete chart and/or pilotbook
• I – Lack of local knowledge
• E – Shoaling
• J – Sea-state, swell and wind