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With a major blue water race in August (i.e Fastnet 2009) and a series of qualifiers I am looking at our boat's navigation needs. I use MacENC now for general sailing and really like the app. One thing that MacENC appears to be lacking is passage planning/route planning in anything other than a manual way. Recognise that with Polar information, it will give a course to steer/next tack based on current location instrument readings but was trying to take a longer view for a given weather forecast.

Some PC based products offer "performance sailing" or predicative "best course" routes features/add-ons based on GRIB weather files and tide predictions. With an Ocens/MacWX subscription and Mr Tides I have the raw data but I am not well educated enough to make use of the data.

Does anyone have any recommendations for software that has this feature?

Is there a development roadmap for MacENC? Does it happen to include this type of feature/add-on?

Equally, does anyone have any recommendations for reading materials on making practical use of GRIB charts/tidal data for passage planning?

I recognise there is a laundry list of question above, but any guidance gratefully received.

Thanks,
Adrian
I read good things about Deckman and Expedition, both packages that will use GRIB forecasts to do predictive routing. They do require MS Windows and are relatively expensive. The key to their success is accurate polars and accurate Wx forecasts.

At this time there is no plan to develop such a routing module for MacENC.

There are many books written on Weather AND Sailing. Head over to Amazon.com and you will find them.



Have you looked at MaxSea... I have version 10 and works very well.
I think the new version is pricey though.
I once had the routing module for MaxSea in my pre-MacENC days and it was a lot of fun to play with. However, trying to find an optimal routing down the West Coast I'd have to plot a waypoint well off Cape Flattery to just get it to route me offshore. Then if I didn't add more waypoints it would very happily route me from the Juan de Fuca Straits to San Diego via Lake Tahoe. Same for any islands in the way...

Scot
Maybe MaxSea thought you had a trailerable boat. Go straight down I-5 at 60 mph and hang a right at San Diego Smile
Hmmm - similar experiences with SatNav while driving across London and being taken on peculiar routes - never as good as a Black Cabbie and his "rat runs"....

For what it is worth, and probably off-topic, I did find some interesting reading and thought I would add it here. Generally the books on navigation or weather never combine how you plan routes (racing or cruising) for a given weather forecast - possibly too applied in nature I guess. However, the following recent articles on Sailing World were a good read and gave an overview of how a boat's polar curve can be used in this context:

http://www.sailingworld.com/from-the-exp...61573.html

http://www.sailingworld.com/from-the-exp...61206.html

And in case there are some talented programers viewing keen to build an add-on the MacENC I found an academic articles on the topic (titled: Optimal Sailing Routes in Uncertain Weather).

I would have to image that with the America's Cup in NZ for several years, some creative engineering lecturers took inspiration for the sailing frenzy that engulfed NZ - see link bellow:

http://www.orsnz.org.nz/conf35/papers/An...onAndy.pdf

Cheers
MaxSea does weather routing. Info here:

http://www.robmello.com/sitegallery/maxsea/routing.html

The key to success is obviously ultra accurate polars and weather data not to mention some pretty heavy duty math on the part of the operating system and SW.
It's also very expensive.
bobetter Wrote:MaxSea does weather routing. Info here:

http://www.robmello.com/sitegallery/maxsea/routing.html

The key to success is obviously ultra accurate polars and weather data not to mention some pretty heavy duty math on the part of the operating system and SW.
It's also very expensive.

That's just an updated version of the one that sent me and Jaga sailing up the Sierras... Even the old one needed good polars and grib files to work. Hope the current one is a bit smarter Wink Actually, the new one looks very much as I recall from 5 years ago. I also recall it was very processor intensive and could take an hour or more (much more?) to calculate a lengthy routing. Of course 5 years ago that was on a processor with significantly less power than today's.

Scot