1. Lesson 3A: Basic Plotting

2. Lesson 3A: Basic Plotting
AGENDA:
Basic chart features
Traffic separation scheme
Visual aids
Tabulated depth charts
Scales
Plotting on a chart

3. CHART NOTES, CHARACTERISTICS
AND SYMBOLS
Traffic separation Schemes:
Indicate outbound and inbound waterways.
Magenta in color

4. Traffic Separation Scheme

5. CHART NOTES, CHARACTERISTICS
AND SYMBOLS
Navigation Aids:
Aids with sound and visual characteristics. Listed and labeled on chart
Usually used as primary navigation
aids for Visual or Radar.

6. Visual Aids’ Characteristics Label

7. CHART NOTES, CHARACTERISTICS
AND SYMBOLS
Notes located throughout the chart give detailed descriptions of danger, obstructions, depths, overhead clearances, etc.

9. CHART NOTES, CHARACTERISTICS
AND SYMBOLS
Scale Conversion Tables:
Used for measuring distance (based on the scale of chart being used).
Used for converting U.S. system of measurement to metric, etc.

10. Tabulated Depths

11. Measuring Distance NEVER use the longitude
scale to determine distances
on a chart.
Latitude is measured along a meridian and one degree of latitude is essentially the same everywhere on the earth.
1 deg Lat = 60 nm
1 min Lat = 1 nm
1 nm = 2000 yds (actually 6,076 feet)
Longitude is measured along parallels of latitude. One degree of longitude will not equal 60 nm except when measured along equator.
@ 0° Lat --- 1° = 60 nm
@ 30° Lat --- 1° = 52 nm
@ 60° Lat --- 1° = 30 nm
Speed =
1 knot = 1 nm/hr (1 nm = 1.15 statutory miles)

12. TERMS AND DEFINITIONS
Navigation Plot: A graphic plot of the movement of a vessel suitably labeled with respect to time, direction, and speed.

13. TERMS AND DEFINITIONS
Course – The direction in which a vessel is steered or “intended” to be steered.
Designated as True or Magnetic.

14. TERMS AND DEFINITIONS Track – The path of intended travel
with respect to the earth as drawn on the
chart.

15. TERMS AND DEFINITIONS
Speed of Advance (SOA) – The speed intended to be made good along the track.
The average speed in knots which must be maintained during a passage to arrive at a destination at an appointed time.

16. TERMS AND DEFINITIONS PIM-
Planned track movement based on required SOA
USS Indianapolis
Indicated every 4 hours
Needed for ALL Voyage Plans
PIM symbol must be different from standard navigation symbols. Ex:
1200Z PIM

17. TERMS AND DEFINITIONS
Nautical Mile – A unit distance used principally in navigation yards equals one Nautical Mile.
Knot – A unit of speed equal to 1 Nautical Mile per hour.

18. MEASURING DISTANCE Distance of 1 NM 1 Degree = 60 NM (Nautical Miles)
1 Minute =
1 Nautical Mile
DISTANCE ALWAYS MEASURED ON LATITUDE SCALE!

19. 10 NM

20. TERMS AND DEFINITIONS View Overall Track (Big Picture)
Use a small scale chart that encompasses the overall area
Great Circle Sailing
General (International)
If transiting open ocean

21. LABELING 1. Visual fix is plotted as a circle.
2. Electronic fix is plotted as a triangle.
3. DR is plotted as a half circle.
4. EP is plotted as a square.
5. Composite is plotted as a circle with a triangle inside the circle.

22. LABELING
6.  Course is labels on top or above the track line. Referenced in 3 digits and always labeled “T” for TRUE and “M” for MAGNETIC.
7.  Speed is labeled below the trackline and always expressed in KNOTS.
8.  DR Time is labeled at an angle to the track line.
9.  Fix Time is labeled in a straight line to the fix.

23. COURSE EXAMPLE C-090ºT (080ºM) S-10 KTS D-1510 YDS 0900 30 1000
C-090ºT (080ºM)
S-10 KTS
D-1510 YDS
0900 30
1000
Always done in PENCIL

24. TRACK EXAMPLE C-090ºT(080ºM) S-10 KTS D-1510 YDS 090705Z 090700Z
Always in Pencil – never erase a track or fixes until NAVIGATOR says it’s OK

25. Plotting Positions on a Nautical Chart
Step 1 - Examine the latitude scale on side of the chart closest to the desired position.
Step 2 - Place the metal point of the compass on the reference parallel.
Step 3 - Spread the compass to reach the desired latitude and make a mark.

26. MEASURING LAT. & LONG.
Charted Latitude and Longitudes are based on the SCALE of the CHART itself.

29. Plotting Positions on a Nautical Chart
Step 4 - Examine the longitude scale on side of the chart closest to the desired position.
Step 5 - Place the metal point of the compass on the reference meridian.
Step 6 - Spread the compass to reach the desired longitude and make a mark.

30. Plotting Positions on a Nautical Chart
Step 7 - Locate the reference parallel and meridian intersection and lightly mark the reference parallel with the longitude marked position.
Step 8 - Without changing the spread of the compass, place the metal point of the compass on the reference meridian.

31. Plotting Positions on a Nautical Chart
Step 9 - Remeasure latitude on the latitude scale and place the metal end on point and swing a arc so that in crosses the one made for longitude.
Step 10 - Mark the desired position where the two arcs crossed( intersected) and label the position.

32. Plotting Positions on a Nautical Chart

33. Plotting Positions on different scales of charts. Coastal Chart
Degrees, Minutes and tenths of a Minute N
1.5-12 E

34. RELATIONSHIP OF TIME/SPEED/DISTANCE
D = S x T
T = D / S x
S = D / T

35. RELATIONSHIP OF TIME/SPEED/DISTANCE
D = S x T
Distance Equals Speed Multiplied By Time.
yds = 12.0 kt x 3min
1200

36. RELATIONSHIP OF TIME/SPEED/DISTANCE
S = D / T
SPEED REQUIRED EQUALS DISTANCE DIVIDED BY TIME
kts = 12.0 nm / 36m
20.0

37. RELATIONSHIP OF TIME/SPEED/DISTANCE
T = D / S
TIME REQUIRED TO TRAVEL 400NM EQUALS DISTANCE DIVIDED BY SPEED.
= 1500yds / 15.0kts
3 min

38. PLOT THE FOLLOWING POSITION
Using chart plot the following position
76º 21’ 36” N
36º 57’ 50.5” W
Label as Anchorage 1
DO NOT ERASE THIS MARK!!

39. QUESTIONS?