Amen. I had an alternator failure a couple of years back and the first of
the electronics to bug out was the GPS. I was very happy to have all the
usual pilotage tools in my lap and properly marked up. I completed the
flight with no functioning radios.

Seth
Comanche N8100R

"Sydney Hoeltzli" wrote in message
...
DeltaDeltaDelta wrote:
Do you people with GPS units (either panel mounted or portable) use only
them when you fly, or do you plan the same route on a map as well and
plot
your position in flight, for backup in case the unit looses pickup?

It's not just "for backup in case the unit loses pickup".

Today, the vast majority of GPS units in use lack a vital ingredient
for proper flight planning:

**TERRAIN INFORMATION**

Certain accidents used to be described as having "the Mark of Loran
Guided Death"

These are accidents where a plane, on the exact centerline of a
direct route from "here" to "there", flew into terrain or obstructions
in crappy wx.

Often terrain or obstructions which they could have avoided, had
they only perused a chart and observed that detouring 3 miles east
would allow them to follow a road through a valley.

The phrase could be updated to "the Mark of GPS-Guided Death".

My point is:
*safe flight is a 4 dimensional problem
*most GPS units only address 3 of these 4 dimensions
*unless you're flying with a GPS/Moving map system which addresses
all 4, better keep your charts and know where you are and what
the terrain along your route looks like
*even if you are, if the power fails or signal is lost, what then?

Sydney (1 panel-mount GPS, 1 handheld GPS, 2 full sets of charts with
a courseline on at least 1 of them)