Wayne.B wrote:
On Sun, 05 Oct 2008 14:23:08 -0400, Marty wrote:

Someone asked for an easy way to figure out how fast Skip was traveling.
Well I found a nice little on-line Haversine (the function to compute
the Great Circle distance between two points) calculator.

http://www.movable-type.co.uk/scripts/latlong.html

Just input the coordinates from two of Skips messages that are one hour
apart and out pops the distance in km. You can do a bit of conversion
from there.
From Skips' 1257 abd 1357 points he only traveled 10Kms, about 6nm.


Cool, good find.

Here's another site that uses a more convenient (for SPOT data) input
format, and returns nautical miles:

http://jan.ucc.nau.edu/~cvm/latlongdist.html

Here's an example from 3:47PM to 5:47PM where they covered 8 nautical
miles in two hours for a VMG of 4 kts. That's not all that bad
considering that they are probably under sail with a knot or two of
Gulf Sream current against them. Looks like they're heading for the
cut through channel in the middle of Frying Pan (Cape Fear) Shoals.

Distance Calculation Results

Distance between 33.9459N 77.1566W and 33.9139N 77.3133W is
8.0482 nautical miles

Source
Latitude : 33.9459N Longitude: 77.1566W

Destination
Latitude : 33.9139N Longitude: 77.3133W

Units for results nautical miles



Thanks Wayne, the one I posted lets you use decimal degrees, the only
thing is the return in KMs, just divide by 1.85 and you get nautical
miles. I put Skip's numbers in for a 12 hour period and got 60nm, not
to bad at all, 120 mile days are nothing to be sneered at.

Cheers
Marty