On Sun, 25 Jun 2006 16:47:18 -0600, Newps wrote:


Not for compatibility reasons. Take your average Boeing 757 used by an
airline. The mode S transponder is registered to the N number. The
airline will never use that N number in flight and that aircraft will fly
under a different identification every day.

It doesn't need to be this way. The controller could "assign" a "code" to
the mode S id. The aircraft would never need to be involved.

Still, from what you describe it apparently doesn't work that way. Oh
well; I guess we're stuck with those base 8 codes.

I suppose that this does provide the benefit of assuring that the object
on the screen is in fact the aircraft the controller thinks it is.

I'm a little surprised, though. I vaguely recall something about these
being too limited for future applications. Perhaps I misunderstood (or am
misremembering).

TIS travels via the mode S data link. TIS-B uses ADS-B's data link. So
no mode S transponder is required.

Right but the transponder will allow others to see you.

Which "others"?

Does that mean that, as soon as those "others" "upgrade", the transponder
will be a thing of the past? No more beacon codes?

- Andrew