S-T
I didn't make the $5K argument, someone else did (see below).
ADSB is stand alone, yes. But if we are to listen to the Anti-NAS arguments presented here, it is the answer to most of them.
I personally don't think ADSB is critical for NAS and I personally do think NAS will work. I was trying to find a compromise position between those that think NAS will create dangers for regionals in D and E. ADSB is that compromise.
An Australian company has designed a Mode-S box with GPS and CDTI. Bought in big enough numbers it could be FITTED for less than $5K per GA aircraft. US and European aircraft may not comply with the Mode-S standard, but it isn't in any AOPA members interest to drag our safety levels down just because they can't comly.
Where the big bucks of open skies is at stake I doubt the likes of BA or Virgin are going to scare off at the cost of a Mode - S. Besides, like i said, they only operate as low as C anyway, NAS isn't an issue there and any attempt to make it so is dishonest.
AK