Hi Norman,
Yes I will report.
Perhaps it will be interesting for some to read about how my study is progressing.
To recap:
- I bought the StarPath
books, but not the online class
- I had in the past purchased, but never used, the Navathome course for the RYA version of the exam. I paid the reactivation fee.
- I am an experienced sailor from
France, and about 20 years ago, I passed the French "Permis Hauturier", the
offshore motorboat license that covers a lot of similar stuff
- Back in the 70's and 80's I had learnt much of that stuff from the Glénans
sailing school in France
- Obviously, I have been mostly a GPS navigator for many years, though I have been keeping my navigation skills in minimal working order through some chart
safety work when planning and
tracking passages.
- I passed ASA 101, 103, 104 in one session, scoring 99%
What I have done so far:
- Watched the "Coastal Navigation: Two-Bearing Fix" video by Tom Tursi (
), which I found interesting because this is about the only place I found with US based exercises (you can decipher some of the exercises from the exercises sheet nailed on the wall). I found them all very easy. The most difficult part was locating the mentioned places on the unfamiliar training chart. I am interested in some other examples of ASA based exercises. I supposed I will find plenty of those in the StarPath ebook I purchased, but haven't gone through it yet.
- started the RYA course, waiting for my US training to arrive in the mail. I did the first 2 sections out of 12 so far. The sections are
1- Chart basics (datum, deviation…)
2- Tides (including tidal streams)
3- Dead reckoning
4- Course to steer
5- Electronic navigation aids (Radar and GPS)
6- Electronic chart plotting (includes NMEA)
7-
passage making
8- visual aids to navigation (water marks, lights, leading lines)
9- pilotage (incl restricted visibility)
10- Meteorology
11- Colregs
12-
Safety and
environment
Clearly I will spend more time on some sections than others.
A couple random things I noticed:
- Both ASA and RYA use a fictitious sailing area with fictitious charts. While the French exam use a real area, the Baie de Quiberon in south Brittany, albeit with a chart that has been frozen in time and will never be updated - the so called training chart #9999, frozen from chart #7033. I was familiar with that area when I passed the French exam, which made it easier to prepare.
- I haven't seen parallel rulers used very much in France. People seem to be mostly using either Cras rulers, or Breton plotters. Therefore we don't use the roses on the charts as plotting devices very much, as the protractors are on the rulers themselves
- the RYA method for tide computations differs significantly from the French way. This was a bit unexpected. I haven't looked at the US way yet, but I suppose it will be closer to the British way than the French way.
The RYA way is to use a tide curve that is specific to the location, while using one tide time only, usually the time of high waters. Then you ignore the time of low waters on either side, in effect assuming that the tide duration is exactly 6 hours.
In the French way, you don't assume that. You divide the duration between an extremum to the next by 6, giving you what we call "tide hour" (heure marée), which is something like 1h04 (as an example).
Where we French approximate things is by using the
rule of the 12th:
- 1 12th of the tide range flows in the 1st tide hour
- 2 12ths of the tide range flows in the 2nd tide hour
- 3 12ths of the tide range flows in the 3rd tide hour
- 3 ____________________________ 4th _______
- 2 ____________________________ 5th _______
- 1 ____________________________ 6th _______
Mathematically, this amounts more or less to approximating the tide curve by a sine curve over half a period, and then fitting a piecemeal affine function to it with 6 segments
The good thing is that it's very easy to do a graph of it using a straight line:
- use 1 x-axis unit for the 1st tide hour
- use 2 x-axis units for the 2nd tide hour
- use 3 x-axis __________ 3rd ________
- use 3 x-axis __________ 4th ________
- use 2 x-axis __________ 5th ________
- use 1 x-axis __________ 6th ________
and then one straight line from low height to high height using whatever scale you want on the y axis
Another thing we have that seems to be unique is the tide coefficient: a number between 20 and 120 where 20 is the "neapest", and 120 is the "springest" tide.
If people find it interesting to read about my studying experience, let me know. If you don't care let me know too. Writing this up is time consuming.
And feel free to point where my
English is wrong or awkward.
Too many things to get done, not enough qualified workers that can 
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