In article ,
"Morgans" wrote:
A PDA or TabletPC-based system may be a great way to go for backup, but
I wouldn't want to rely on it for anything--ever.

I always thought portable GPS's were for backup, and just another tool in
the pilot's bag of tricks!

It depends on your definition of "backup." If you don't have an IFR
certified GPS, you can not file for IFR enroute or approaches. However,
I routinely file airways and then ask for direct, effectively using my
portable GPS as a primary navigational reference. As long as you are in
radar contact, this practice is legal.

My point is that the portables from Lowrance and Garmin are more
reliable, and use navigation data that is much more reliable, than many
of the TabletPC/PDA software vendors.

In the case of AnywhereMap, I've found fairly obvious and frequent
errors in their navigation data. They are missing low-level obstacles.
The software does not compute great-circle routes. The software was
otherwise riddled with bugs and quirks that made it impossible to use as
any type of reliable IFR reference, in my opinion. It did do well for
weather display, though it only displays a fraction of the XM weather
information that the Garmin 396 displays. There still exists a bug that
makes it impossible to reliably use the PocketPlates product along with
AnywhereMap--this was going to be fixed "soon" months ago.

If I had a panel-mount GPS with the Jepp database, I probably would have
kept the AnywhereMap system. It should be fine for VFR-only use.




JKG