>
> Yes Jeff- good feedback but I am still working on that comment that mode S is
> only required above 18000' , most folks around here (within 30 miles of a
> major airport) seem to think that we will need it at all altitudes.
> Bill
> -
That is not the case in the US. The 2020 rule requires ADS-B out. You are
allowed to equip with either (Mode S) 1090-ES or UAT out. Other planes with
ADS-B in will see either, as will the FAA. The Mode-S is received by Radar and
the UAT is received by the ADS-B towers (they look like a little outhouse with
a small antenna). In a congested area like the San Diego and Los Angeles areas
it shouldn't make any difference as the FAA has lots of ADS-B towers. However,
in remote areas, it does make a difference.
Flying internationally (like crossing into Mexico or flying into Canada), or
flying at or above 18,000', you will be required to have 1090ES.
On our trip last weekend, I was flying my KR and broadcasting UAT out. My
buddy flew the exact same route at the exact same altitude in an RV-7A using a
Dynon feeding a headless Trig TT22 Mode S transponder. We flew direct from
KRYN (Tucson) to KLAM (Los Alamos [near Santa Fe]). The report for his Mode-S
transponder showed the complete flight from Tucson to Santa Fe. My report only
showed the last hour of the flight. We were flying over a very remote and
desolate area for most of the flight. But what the reports showed is that they
saw him on radar for the whole trip. My ADS-B out (and In) was out of range
from an ADS-B tower for over half of the trip. Of course I was also able to
see the RV-7's 1090ES transmissions and was tracking him on my GPS.
-Jeff Scott
Los Alamos, NM
