experience

how do people know so much.

wait a second, why do people bother to find out this stuff?

not that im complaining about the mass of useful knowledge i can glean from this forum

Edited by mike ellis

Originally posted by mike ellis wait a second, why do people bother to find out this stuff?

In my case, there is a long story about whether keelboat class rules and/or sailing instructions should require VHFs for racing a mile or two offshore, or whether (as I argued) mobiles are an acceptable subsitute. I was involved in framing such rules at the time. It was asserted that mobiles are not a subsitute because the coastguard cannot use them for position finding. At the time I accepted that at face value but it appears to be 100% wrong.

 

Is it the coastguard who knows where your mobile is calling from or the Mobile company?  And if your phone is only being received by 1 cell I think the area identified might be quite large!

Garry

Originally posted by Garry Is it the coastguard who knows where your mobile is calling from or the Mobile company?  And if your phone is only being received by 1 cell I think the area identified might be quite large!

The second point is true but the central Solent is hardly the back of beyond. Regarding the first point, I am told by people involved in Mountain Rescue that they can readily obtain triangulation data for emergency mobile callers. I don't see why the coastguard would be any different.

That'll be cause the LOS range on lifeboat is relatively short so the +/- errors don't grow too big.  As mobile masts are more tightly spaced than the VHF masts you get more inputting into position calculation and, generally, better angles of cut.  So near any populated shore you are unlikely to be only in one cell.  Main catch is the range, VHF masts are taller so have better range.  Of course if you know where you are, like all good mariners should, it doesn't matter a jot what method you use to contact the coastguard as long as you do it while you still can!