2 years or 10 years means it's probably not a great idea to buy a Mode S
transponder. ADS-B is a great technology and the sooner it's available, the
better.

Bill D


"Paul Remde" wrote in message
news:bZ3qj.17165$9j6.13971@attbi_s22...
Hi Marc,

The maps I've seen of the rollout of the ADS-B ground stations will be
much sooner than you imply.

And even without the ground stations a batch of gliders with ADS-B units
would see and avoid (hopefully) each other - similar to FLARM.

But I'm sure (sincerely) that you know more about this than I do. I hope
you'll join us for the meeting.

Paul Remde

"Marc Ramsey" wrote in message
...
Paul Remde wrote:
My dream is that is 1 to 2 years from now many glider pilots will be
voluntarily using low cost ADS-B transmitter/receiver units. They will
show nearby traffic where you are AND they will allow you to see nearby
traffic - not only traffic that has an ADS-B transmitter. If you are
near a radar controlled airport with ADS-B transmitting you would also
see all traffic that has a transponder because they broadcast that
information to ADS-B receivers - cool!

The situation is a bit more complicated than the dream, unfortunately.
Two aircraft equipped with ADS-B transceivers of the same type (UAT or
1090ES) will detect each other when within proximity, right now, anywhere
in the US. The ability to obtain traffic advisories for aircraft
equipped with the other form of ADS-B, or using Mode C or S transponders,
is dependent on the existence of a network of ground stations. These
ground stations are already in place along the coast from New York down
to Florida, in Alaska, and a few other random places. The contracts to
complete the system were just awarded last fall, it will be 10+ years
before all of the ground stations are in place.

So, for the next few years, an ADS-B transceiver will be nothing more
than an expensive underutilized FLARM-like device in most areas of the
US. That said, if we don't start pushing for what we want, right now, we
probably won't be happy with what we can get when the network is complete
in 2020 or so...

Marc