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Old December 29th 05, 03:58 AM posted to rec.aviation.owning
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Default GPS396 terrain warnings near airports

When I fly with my GPS396, I usually don't put in a flight plan or any
direct-tos; I use the panel mounted KLN94 for that. I use the 396 just
for weather, terrain, and additional situational awareness. I had
never heard the spurious terrain warnings near airports that Dave
Butler reported in another thread. Btw last week I updated the
software in the 396, but I never heard the warnings before that either.


Well today I heard them. And the difference was, I had a direct-to
waypoint which was NOT the airport programmed in and active. I was
safety pilot and we were doing hood work with VFR flight following. I
had the IAF for the GPS approach set as the direct-to waypoint, but for
various reasons including conflicting traffic and an incoming weather
front, we decided to break it off and just do a normal VFR pattern and
land. From the base-to-final turn all the way in, the GPS 396 gave
terrain warnings. We had done two approaches earlier in the flight
without a direct-to active in the GPS 396, and it stayed quiet all the
way down to either minimums or the runway. But as soon as we landed
with a direct-to (which was NOT the landing airport) active, it
squawked all the way down from 500 AGL.

So in my experience, having a direct-to waypoint and landing somewhere
else must confuse the GPS396 into giving terrain warnings as you come
in to land.