# Nav problems

Using lapware. Can’t seem to get an email through to them for support, anyone else have that issue? How do I figure where a great circle route recrosses the equator?

[QUOTE=mattmclain@yahoo.com;195458]Using lapware. Can’t seem to get an email through to them for support, anyone else have that issue? How do I figure where a great circle route recrosses the equator?[/QUOTE]

If a GC crosses twice wouldn’t they be 180 degrees apart?

[QUOTE=Kennebec Captain;195467]If a GC crosses twice wouldn’t they be 180 degrees apart?[/QUOTE]

Unless a “broken GC” I assume??

[QUOTE=Kennebec Captain;195467]If a GC crosses twice wouldn’t they be 180 degrees apart?[/QUOTE]

If “recrosses” wasn’t a typo then yes, 180° longitude between the two crossing points sounds right.

Since the earth is 180 degrees E and W instead of 360 all around you have to draw it out. But that takes like 5 seconds.

If it’s a theory question about great circles, except in the special of the equator itself all great circles will intersect the equator at two points, 180 degrees apart.

In the case of a great circle track; if the end points are on opposites side of the equator it will cross the equator only once.

The only time a track would cross twice is in the case of the end points both on the same side of the equator and going round the long way.