Hank Rausch wrote:
I would vote for (a), modified, as follows:
snip
... Light planes would have an ADIZ at
the current radius; faster ones at an expanded envelope.

In order to implement this, some means of characterization needs to be
in place to enforce it. I think current sensor technology allows this.
snip

What if, instead of just 4096 squawk codes, there was
a way to allow each airplane to have it's own unique code?
If that code were registered at the FAA along with the N number,
then a radar return would allow automated lookup of aircraft type.

I know TWO mode C transponders per aircraft wouldn't exactly work,
but something along those lines?
--wade