If you are travelling a short distance but across a pretty strong tide, the quick CTS method can be quite useful. In this instance you will not need dividers simply a plotter but you will need all the other associated information to formulate your CTS. See Course to Steer.
I have also made a YouTube video to support the CTS both full and quick, to just see the quick method fast forward to the very end of the video.
To work up a quick CTS you will still need to know the following:
- Understand how to use a plotter
- Be able to find the correct tidal hour or hours
- Be able to ascertain whether we are in neaps or springs
- Understand how to read a tidal stream atlas or tidal diamonds (I am using the atlas for this blog)
- Understand the application of variation and deviation
As this is a quick CTS I am going to use the same information as I did in the full CTS blog so I already have the following information:
- Tidal stream for the hour in question is 1.4kts
- Tidal direction fo the hour is 101° (T)
- My estimated boat speed is 5kts
Ground Track
Draw on the ground track from Norris (PHM) to Clashot (NCM) in exactly the same way as I would a normally constructed CTS.
Using the plotter to construct the CTS
The plotter alone can now be used to construct the CTS. As long as the same size units are used for tidal stream rate and boat speed the angle will be the same as if constructed using units from the Latitude scale.
Quick course to Steer
I have plotted the quick CTS alongside the standard / properly worked CTS - you can see that the lines run parallel. I have used 1.4 inches on the plotter for my tide and 5 inches on the edge of the plotter for my boat speed.