I'm not sure I understand because a cruise ship
would sail a great circle route which would take the ship the least amount of time and cost the least in fuel
etc. This would mean a heading that changes between LA and Hawaii
...unless they need to do some weather
So to do a set and drift calculation, I need to know the speed of the ship and the set and drift of the ocean current
to come up with a course to steer by. What is the speed of the ship? Ocean currents change all the time, so that would be difficult if not impossible to calculate....but you could always throw out a hypothetical vector for the ocean current
causes some leeway on a ship as well....so I would need a vector for that.
Are you asking for the initial heading for the first leg of a great circle route when leaving the harbor in LA?