
Post by
zezo | 2019-11-28 | 15:07:26
This router has one quirk - the boat can't sail backwards towards the origin.
In this case it tries to reach Brest the long way around - via Ireland, but stops short of the destination because it requires sailing back.
That will fix itself once you reach about 40N (assuming you are not running along the coast)
In the meantime you have to estimate the final part of the route yourself. Click the last black dot to switch the forecast and check the weather.
You may also compare the last blue line along the East and West route - they correspond to the same moment in time. The straight segment between them represents the "forbidden zone". In reality it should be convex. For the checks use the DTF indicator on the right hand side of the status bar. The chart does not use proper projection, so the visual distances are misleading - at that latitude 500 nm N-S look like 300 E-W.
The "quirk" is result of the optimization that allow the router to be run as responsive online service. Avoiding it is possible, but would make it about 10 times slower.