"Jay Maynard" wrote in message
...
On 2008-09-05, Mike wrote:
The algorithm is part of the ICAO standard, so if other countries aren't
doing this, they are doing so outside the standard.

Uhm...since the US algorithm is quite dependent on the US rules for
assigning registration numbers, it would not work at all for, say, the UK.
(Although, in fairness, the UK's algorithm, as well as that for countries
that use all-alphabetic registration systems, would be quite a lot simpler
than the US one.) That either says it's not in the ICAO standard, or else
there's more than one.

I haven't read the standard, but the hard wired serial number in the ModeS
transponder is refered to as the ICAO ID. I'm also quite sure the standard
exists in the ICAO convention.