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I am finding angle between ship's heading and component in wave (wave's angle of attack), not sure if ES is a right place to ask this type of question.

Should it be the difference between mean wave direction and vessel's azimuth.

Thank you for your time and concern reading my question,

Sincerely,

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  • $\begingroup$ I believe the answer depends on how the data is going to be used. You mention a component, ocean swell is tracked by direction, period, and amplitude of the swell, these are often divided into different components, i.e. a 1 meter 5sec swell at 275 degrees and a .7 meter swell at 15 sec and 200 degrees. If you are looking for a general effect than your answer is likely ok, but if you want to know the characteristics of a component of the swell you need to explain the question a bit more clearly. $\endgroup$ – user824 Jun 4 '19 at 21:50
  • $\begingroup$ Sorry, I should make it more clear. Are there any different between vessel's heading and the azimuth. Let's say I am moving from 1 coordinate (lon 1, lat 1) to the other coordinate (lon 2, lat 2), vessel heading is calculated from Four-quadrant inverse tangent between sin(delta lon) * cos(lat2) and cos(lat1) * sin(lat2) - sin(lat1)*cos(lat2)*cos(delta lon) . While for azimuth, I am taking into account of 'World Geodetic System 1984' $\endgroup$ – Ewok The Sith Lord Jun 5 '19 at 18:19
  • $\begingroup$ Heading is the direction the vessel is pointing it is equivalent to the Azimuth. The true course may be different than the heading due to winds and current. I am still not clear on why the wave angle is important. $\endgroup$ – user824 Jun 5 '19 at 23:48
  • $\begingroup$ Hi Friddy, I am calculating vessel's speed loss during the effect of adverse weather. Wave is one of the main component and to do so, a relative angle between vessel and wave has to be treated as input. Do you know any source provide formula calculating vessel's heading beside Mercator Sailing Formula $\endgroup$ – Ewok The Sith Lord Jun 6 '19 at 13:59