[a2sail]

Having a "scorched earth" mentality when sailing offshore, I would like to have a "hard" copy of a Routes waypoints. I can print the Lat/Lon for each waypoint, but not the Bearing and Distances. Any thoughts on how this might be done.

Thanks,

ajsail

[Jade]

One thing that can be done easily is to transfer a selected Route into a KML file. This file can then be opened in Google Earth to view/print.

[a2sail]

Jade:

thoughts are most appreciated, but, seems like GE prints out the route map & WP location. I would like to have just a sheet listing: of the Lat/lon, WP, Range and Bearing. Of course, I may be missing something in GE. application that might allow me to do that.

PS. You may be one of the few folks that have used a sextant!

ajsail

initiative

[Jade]

If you can import your route waypoint list into a spreadsheet, then you can add two extra columns to calculate the range and bearing between waypoints.

Or you can simply take a screen shot of the route dialog in MacENC and print it if there are not too many waypoints in the route.
[image]http://i558.photobucket.com/albums/ss23/jade_808642/Route.png[/image]

[GPSNavX]

I like to use the Macs built in screen capture and make a PNG..

http://www.gpsnavx.com/images/sampleCapture.pdf

http://macdevcenter.com/pub/a/mac/2003/0...nshot.html

[a2sail]

You are right about that - I can import into Mac Numbers or Excell, but they will only show WP and Lat/Lon. I still have to copy in each Bearing and Distance. Just time consuming!

thank you,

ajsail

[a2sail]

Jade;

missed your screenshot comments - that might do it..

thanks,,

ajsail

[Jade]

P.S. There are formulae to automatically calculate the range and bearings that can be used in the spreadsheet.

[Ron]

Jade,
Will you share the formulae to calculate distances and bearings in a spreadsheet?
Cheers,
Ron

[Jade]

Ron,

For short distances between 60ºN and 60ºS:-

The distance run between 2 waypoints is roughly equal to the square root of (the difference in Latitudes squared plus (the difference in Longitudes times the departure at mid Latitude) squared);
D=sqrt((L2-L1)^2 + ((Lo2-Lo1)*cos(L1+(L2-L1)/2))^2)

The course is approximately equal to the angle whose sine is (the difference of Latitudes divided by the distance run)).
c=asin((L2-L1)/ D )

The course © must be corrected for quadrant and the latitudes and longitudes must be in the same hemisphere.


For great circle computations:-

D=60*acos((sinL1 * sin L2) + (cosL1 x cosL2 x cos t)]
C=asin[(cosL2 * sin t)/(sin D)]

For details and limits, please refer to
Dutton's Navigation and Piloting, page 661 paragraph 2914, "The Sailings"

[Jade]

Ron,

The first formula for short distance above needs to be corrected if Latitudes and Longitudes are in degrees:
D=60*sqrt((L2-L1)^2 + ((Lo2-Lo1)*cos(L1±(L2-L1)/2))^2)

and the second formula corrected for degrees instead of radians:
c=Degrees(asin(60*(L2-L1)/D))