D-6 Chartwork Exercise

Objectives

The student will:

• Apply the knowledge gained in Sections D-4 and D-5

The Cruise - Departure

You are aboard a friend’s 7m power cruiser, leaving Boutcher Bay on the north coast of CPS Island. By taking bearings on Summers Light and the nearby VHF tower, you have established your exact position as L 49º13.7’N, Lo 123º37.9’W.

The Cruise - Destination

An urgent radio message requires your friend to make a quick run to Seymour Landing on the south-east side of Bowen Island (L 49º20.5’N, Lo 123º21.2’W) and she asks you to act as navigator.

The Boat

The boat has a reliable steering compass with zero deviation, a hand-held bearing compass, a depth finder and a knotmeter but no electronic navigational aids. You plan to travel at a speed of 12 knots. Use a magnetic variation of 20ºE for this cruise.

Pinpointing a Fixed Destination

After studying the chart, you select Pt Cowan Lt (L 49º20.2’N, Lo 123º21.6’W) as your destination and carefully inspect the chart for hazards along the proposed route.

Question 1

What hazards if any, lie within 2 miles of the track?

Seymour Landing

Boutcher Bay

Draw the Track

• Step One: Find the given latitude and longitude of the departure point on the chart and mark the point

• Step Two: Draw a line from there to the black dot of the magenta symbol of Pt. Cowan Light

Latitude: L 49º13.7’N

Longitude: Lo 123º37.9’WPosition

13’

14’ 37’

Plotter Roseindicates a bearing of

059°

C 059

S 12.0

019 ½° E

We will use a magnetic variation of 20° E for this cruise

Date: Vessel: Navigator:

Time Obs Lat Long T V M D C Speed Dist. ETA Remarks

Log Entries

1205 FIX 49°13.7’N 123°37.9’WDepart for Point Cowan Lt.

Question 4

What is the course to steer by compass ?

T V M D C

039 03920E 0059

C 059

S 12.0

Variation20° East039°

Magnetic

/ 039 M

Question 5

What is the length of the track?

Side Scale 1’ latitude = 1nm

12.4 nm

Answer to Question 5

C 059

S 12.0/ 0

39 M

1205 FIX 49°13.7’N 123°37.9’WDepart for Point Cowan Lt.

Date: Vessel: Navigator:

Time Obs Lat Long T V M D C Speed Dist. ETA Remarks

Log Entries

059 20E 039 0 039 12.0 12.4M

Question 6

At a speed of 12.0 knots, what is the expected duration of the cruise?

60D = St

60 x 12.4 = t12

5 x 12.4 = 62 minutes

Question 7

How far will the boat travel in 10 minutes

D = 60

S x T 12.0 x 10= = 2 nm

You will travel 2.0 nm in 10 minutes

60

Question 8

The boat travels one mile on a litre of fuel. There is no fuel supply at Seymour Landing and you plan to return to CPS Island. What is the minimum amount of fuel you should have on board?

Minimum FUEL required is (1 mile / litre):12.4 litres to Seymour Landing (1/3)12.4 litres return (1/3)12.4 litres reserve (1/3)

37.2 litres total (3 x 12.4)

Question 9

If the light at Pt Cowan is partly obscured and is not visible for more than one mile, what other aids to navigation and/or landmarks might you use? Look for aids that will give you a good FIX as you approach Pt Cowan.

Cape Roger Curtis Light

Other navigation and/or landmarks

Microwave towers

C 059S 12.0/ 0

39 M

Port Atkinson

Light

Summers Light

Microwave towers

Cape Roger Curtis Light

Port Atkinson

Light

Summers Light

Plotting on the Chart

You depart the Boutcher Bay Fix at 1205.

Mark the 1210 DR position on the course line and others at 10-minute intervals thereafter.

C 059

S 12.0/ 0

39 M

Depart & DRs

1210

1205

1.0 Mile

1220

2.0 Miles

1230

1240

1250

1300

2.0 Miles

2.0 Miles

2.0 Miles

2.0 Miles

Question 10

What is the ETA Pt Cowan Lt?

From #6, cruise duration = 62 minutes

ETA = 1205 + 62 (1 hour + 2 minutes)

1205 + 1hr + 2min = 1307

ETA = 1307

Date: Vessel: Navigator:

Time Obs Lat Long T V M D C Speed Dist. ETA Remarks

1205 FIX 49°13.7’N 123°37.9’W 059 20E 039 0 039 12.0 12.4MDepart for Point Cowan Lt.

Log Entries

13071205ETA Point Cowan Lt.

Question 11

At 1225, Summers Light bears 231ºM by hand-bearing compass. Are you on track, right of track or left of track?

251 20E 231

T V M D C

2511225

Right of Track

/ 231 MC 059 / 0

39 M

S 12.01210

1220

1230

1205

251°

231° Magnetic

Rotate Plotter Rose to 251°

Variation20° East

231° Magnetic

Summers Light bears 231° Magnetic

Date: Vessel: Navigator:

Time Obs Lat Long T V M D C Speed Dist. ETA Remarks

1205 FIX 49°13.7’N 123°37.9’W 059 20E 039 0 039 12.0 12.4MDepart for Point Cowan Lt.

Log Entries

1205ETA Point Cowan Lt.

1225 Brg 251 20E 231 0 231 Summers Lt.

Plotting and Labeling

At 1253, Cape Roger Curtis Lt bears 304º M by hand-bearing compass and Pt Atkinson Lt bears 040º M by hand-bearing compass.

Plot and label the 1253 LOPs and the 1253 FIX.

Step 1: Convert to TRUE

324 20E 304

060 20E 040

T V M D C

Cape Roger Curtis Lt

Pt Atkinson Lt

1240

1250

1300

324/ 304 M

324°

304° Magnetic

Rotate Plotter Rose to 324°

Variation20° East

304° Magnetic

Cape Roger Curtis Light bears 304° Magnetic

1240

1250

1300

060 / 040 M

324/ 304 M

060°

040° Magnetic

Rotate Plotter Rose to 060°

Variation20° East

040° Magnetic

Point Atkinson Light bears 040° Magnetic

Date: Vessel: Navigator:

Time Obs Lat Long T V M D C Speed Dist. ETA Remarks

1205 FIX 49°13.7’N 123°37.9’W 059 20E 039 0 039 12.0 12.4M Depart for Point Cowan Lt.

1205 1307 ETA Point Cowan Lt.

1225 Brg 251 20E 231 0 231 Summers Lt.

1253 Brg1 324 20E 304 0 304 Cape Roger Curtis Lt.

1253 Brg2 060 20E 040 0 040 Pt. Atkinson Lt

1253 FIX 49°17.3’N 123°22.5’w Distance travelled since 1205 10.6M, SMG 13.3 kn

1253 012 20E 352 0 352 12.0 2.9M Change course

1253 1306 ETA Point Cowan Lt.

1306 FIX Close aboard Point Cowan Lt.

1315 Arrive Seymour Landing

Log Entries

1225 Brg 251 20E 231 0 231 Summers Lt.

1253 Brg1 324 20E 304 0 304Cape Roger Curtis Lt.

1253 Brg2 060 20E 040 0 040 Pt. Atkinson Lt

1240

1250

1300

060

1253

/ 040 M

324/ 304 M

1253 FIX

L49°17.3’NLo123°22.5’W

Speed Made Good

C 059

S 12.0/ 0

39 M

1210

1205

1220

1230

1240

1250

1300

324/ 304 M

10.6 nm

CMG 070 / 050 M

070°

SMG 13.3

S = 60 x D

T60 x 10.6

= = 13.25

SMG between 1205 & 1253 is 13.3 knots

48.013.3

050° Magnetic

1253

Date: Vessel: Navigator:

Time Obs Lat Long T V M D C Speed Dist. ETA Remarks

1205 FIX 49°13.7’N 123°37.9’W 059 20E 039 0 039 12.0 12.4M Depart for Point Cowan Lt.

1205 1307 ETA Point Cowan Lt.

1225 Brg 251 20E 231 0 231 Summers Lt.

1253 Brg1 324 20E 304 0 304 Cape Roger Curtis Lt.

1253 Brg2 060 20E 040 0 040 Pt. Atkinson Lt

1253 FIX 49°17.3’N 123°22.5’w Distance travelled since 1205 10.6M, SMG 13.3 kn

1253 012 20E 352 0 352 12.0 2.9M Change course

1253 1306 ETA Point Cowan Lt.

1306 FIX Close aboard Point Cowan Lt.

1315 Arrive Seymour Landing

Log Entries

1225 Brg 251 20E 231 0 231 Summers Lt.

1253 Brg1 324 20E 304 0 304Cape Roger Curtis Lt.

1253 Brg2 060 20E 040 0 040 Pt. Atkinson Lt

1253 FIX 49°17.3’N 123°22.5’wDistance travelled since 1205 10.6M, SMG 13.3 kn

Question 15

From the 1253 fix, what is the true course to reach Point Cowan Light?

1240

1250

1300

060

1253

/ 040 M

324/ 304 M

012°

352° Magnetic

C 0

12/ 3

52 M

S

12

CMG 070 / 050 M

SMG 13.3

New Course

Question 16

What is the corresponding compass course to steer?

012 20E 352 0 352

T V M D C

Question 17At 1253, how far are you from Point Cowan Light?

2.9 nm

2.9 nautical miles

Date: Vessel: Navigator:

Time Obs Lat Long T V M D C Speed Dist. ETA Remarks

1205 FIX 49°13.7’N 123°37.9’W 059 20E 039 0 039 12.0 12.4M Depart for Point Cowan Lt.

1205 1307 ETA Point Cowan Lt.

1225 Brg 251 20E 231 0 231 Summers Lt.

1253 Brg1 324 20E 304 0 304 Cape Roger Curtis Lt.

1253 Brg2 060 20E 040 0 040 Pt. Atkinson Lt

1253 FIX 49°17.3’N 123°22.5’w Distance travelled since 1205 10.6M, SMG 13.3 kn

1253 012 20E 352 0 352 12.0 2.9M Change course

1253 1306 ETA Point Cowan Lt.

1306 FIX Close aboard Point Cowan Lt.

1315 Arrive Seymour Landing

Log Entries

1225 Brg 251 20E 231 0 231 Summers Lt.

1253 Brg1 324 20E 304 0 304Cape Roger Curtis Lt.

1253 Brg2 060 20E 040 0 040 Pt. Atkinson Lt

1253 FIX 49°17.3’N 123°22.5’wDistance travelled since 1205 10.6M, SMG 13.3 kn

1253 012 20E 352 0 352 12.0 2.9M Change course

Question 18 & 19

Assuming the same Speed Made Good, how long will it take you to reach Pt Cowan Light?

What is the new ETA at Pt Cowan Light?

1253 + 13 minutes = 1306

t = 60 x D

S60 x 2.9

= = 13.1 min 13.3

13 minutes

ETA

Date: Vessel: Navigator:

Time Obs Lat Long T V M D C Speed Dist. ETA Remarks

1205 FIX 49°13.7’N 123°37.9’W 059 20E 039 0 039 12.0 12.4M Depart for Point Cowan Lt.

1205 1307 ETA Point Cowan Lt.

1225 Brg 251 20E 231 0 231 Summers Lt.

1253 Brg1 324 20E 304 0 304 Cape Roger Curtis Lt.

1253 Brg2 060 20E 040 0 040 Pt. Atkinson Lt

1253 FIX 49°17.3’N 123°22.5’w Distance travelled since 1205 10.6M, SMG 13.3 kn

1253 012 20E 352 0 352 12.0 2.9M Change course

1253 1306 ETA Point Cowan Lt.

1306 FIX Close aboard Point Cowan Lt.

1315 Arrive Seymour Landing

Log Entries

1225 Brg 251 20E 231 0 231 Summers Lt.

1253 Brg1 324 20E 304 0 304Cape Roger Curtis Lt.

1253 Brg2 060 20E 040 0 040 Pt. Atkinson Lt

1253 FIX 49°17.3’N 123°22.5’wDistance travelled since 1205 10.6M, SMG 13.3 kn

1253 012 20E 352 0 352 12.0 2.9M Change course

1253 1306ETA Point Cowan Lt.

Arrival

You pass Point Cowan Light close aboard exactly at the time calculated.

Date: Vessel: Navigator:

Time Obs Lat Long T V M D C Speed Dist. ETA Remarks

1205 FIX 49°13.7’N 123°37.9’W 059 20E 039 0 039 12.0 12.4M Depart for Point Cowan Lt.

1205 1307 ETA Point Cowan Lt.

1225 Brg 251 20E 231 0 231 Summers Lt.

1253 Brg1 324 20E 304 0 304 Cape Roger Curtis Lt.

1253 Brg2 060 20E 040 0 040 Pt. Atkinson Lt

1253 FIX 49°17.3’N 123°22.5’w Distance travelled since 1205 10.6M, SMG 13.3 kn

1253 012 20E 352 0 352 12.0 2.9M Change course

1253 1306 ETA Point Cowan Lt.

1306 FIX Close aboard Point Cowan Lt.

1315 Arrive Seymour Landing

Log Entries

1225 Brg 251 20E 231 0 231 Summers Lt.

1253 Brg1 324 20E 304 0 304Cape Roger Curtis Lt.

1253 Brg2 060 20E 040 0 040 Pt. Atkinson Lt

1253 FIX 49°17.3’N 123°22.5’wDistance travelled since 1205 10.6M, SMG 13.3 kn

1253 012 20E 352 0 352 12.0 2.9M Change course

1253 1306ETA Point Cowan Lt.

1306 FIXClose aboard Point Cowan Lt.

Docked

At 1315, you dock at Seymour Landing.

Date: Vessel: Navigator:

Time Obs Lat Long T V M D C Speed Dist. ETA Remarks

1205 FIX 49°13.7’N 123°37.9’W 059 20E 039 0 039 12.0 12.4M Depart for Point Cowan Lt.

1205 1307 ETA Point Cowan Lt.

1225 Brg 251 20E 231 0 231 Summers Lt.

1253 Brg1 324 20E 304 0 304 Cape Roger Curtis Lt.

1253 Brg2 060 20E 040 0 040 Pt. Atkinson Lt

1253 FIX 49°17.3’N 123°22.5’w Distance travelled since 1205 10.6M, SMG 13.3 kn

1253 012 20E 352 0 352 12.0 2.9M Change course

1253 1306 ETA Point Cowan Lt.

1306 FIX Close aboard Point Cowan Lt.

1315 Arrive Seymour Landing

Log Entries

1225 Brg 251 20E 231 0 231 Summers Lt.

1253 Brg1 324 20E 304 0 304Cape Roger Curtis Lt.

1253 Brg2 060 20E 040 0 040 Pt. Atkinson Lt

1253 FIX 49°17.3’N 123°22.5’wDistance travelled since 1205 10.6M, SMG 13.3 kn

1253 012 20E 352 0 352 12.0 2.9M Change course

1253 1306ETA Point Cowan Lt.

1306 FIXClose aboard Point Cowan Lt.

1315Arrive Seymour Landing

• You made it – congratulations!• Homework: Complete Cruise A• Password is “abc” (minus quotes)