RYA day skipper Chart theory notes
Recently I passed my RYA Day skipper theory and thought I would share my notes for my ChartWork
- Tidal Stream Predictions = Tidal Stream Diamonds
- Measure boat Distance on Longitude ( Use side not the bottom)
- To work out range of the tide Minus High Water( HW) from Low Water (LW) and use this to see if the tide Spring or Neaps
- Tidal Stream Diamonds = Spring First Value , Neaps Second Value ( Degree = True ( T ) )
- Tidal Stream Atlas is Map of Direction of Tides = Neaps First Value, Spring Second Value
- Tidal Streams ( 04 = 0.4 )
- Use plotter right way , make sure angle makes sense and is direction of travel
- Windward is the Side of the boat the wind is coming from ( looard is opposite side )
- Lattitude Measured in Degrees then Minutes ( 60′ in 1 °) then decimal (
- True north ( T) is Direct via the Map, no Map Offset ( variation ) 120° (T)
- Magnetic is 120° (M) measured on the Boat
- True Measurment to Magnetic Measurement = West = + the Variation , East = – the Variation
- Magnetic to true, add east or subtract west.
- The true bearing of the transit is 068° (T) – 4° E = 064(M).
- 1knot = Mile per hour
- Round up SOG to nearest knot
- GPS waypoint use BTW not COG for Bearing
- Cable = 1/10 of a Nautical Mile
- Example (T) true course is 014°, with leeway of – 6° = 008°(T).variation is given as + 7° west which is added to give a course of 015° (M) Apply the deviation which would normally looked up in the deviation table, but in this case, is given as 4° east which is subtracted to give a course of 011°(C) compass.
- Leeway would be 5° down wind so the ground track would be 275°(M). ( 270 Heading + 5 ) To counteract for the leeway and maintain the desired course over the ground, steer 5° towards the wind 265°(M). This would give a ground track of the desired 270°(M).
- Waypoint = Way through not end
- Plot Course Then Course to Steer = Tidal Move Point (c) + Knots with Cross of Plot Course
- SOG ( Speed Over Ground ) = A – I
