Bill Daniels wrote:
This seems a far better idea than built-in 121.5 MHz ELT's.
http://www.vpos.no/

I wonder if it could work in the USA.

A different GPRS module would be required for US frequencies. Digital
signal coverage is sparse in wilderness areas here. I've also noticed
that even in areas with coverage, GSM signals can't be received much
over 5000 ft AGL, whereas analog cell signals work to at least 18K.
Base station antenna technology must have improved...

Marc