(Snowbird) writes:

I agree entirely that a handheld GPS in the flightbag is an excellent
safety investment

Well, just to clarify my views: a handheld GPS in the flightbag
is next to useless. It has to be set up, turn on, and acquired
at the beginning of the flight to have practical value if things
go south.

I can see how that would be helpful, but I'm not sure I would be that
strident about it. Again, the most important thing in IMC is to keep
the plane right-side up; the second most important thing is to
maintain altitude and airspeed. Unfortunately, the GPS does not help
at all with any of those -- in fact, it does not come into play until
everything else is calm (or at least stabilized), and you decide it's
time to start heading for an airport.

I fly around with two GPS on and acquired in the cockpit, and
I've never "tuned" one yet . I have selected a navaid or
airport -- is that what you mean?

Exactly. If ATC says (for example), "ABC proceed direct XYZ VOR," and
you don't have a panel-mounted IFR GPS, you have to tune, identify,
and twist for XYZ on the nav radio regardless. If you are using a
handheld GPS, then you *also* have to fiddle with the buttons to set
XYZ as the next waypoint. That's a higher workload, not a lower one
It may well be worthwhile (for the situational awareness benefits you
mentioned), but you cannot argue that it makes the cockpit less busy;
on the contrary, it's one more thing to do. I tend to use my handheld
GPS when things are calm -- when I'm busy, I don't have spare time to
mess with it, and I just stick to the VOR, ADF, and DME. If I had a
panel-mounted IFR GPS, again, things would be different, since it
could be my primary navigation device.

The point is: A moving map GPS is a significant aid to situational
awareness whether the GPS has anything selected, or not. It will
always tell you where you are relative to nearby airports and
navaids.

My stationary paper map tells me the same thing with a much bigger
display higher resolution, but I agree that moving maps are neat, and
I'd love to have a big one on my panel.

So it doesn't have to increase workload one iota.

Remember, I mentioned a handheld originally -- that cannot be your
primary means of navigation, so it's always an *extra* thing to tune.
It has a higher cost in workload, though it's fair to argue that for
you (and many other pilots) it also has a higher benefit in
situational awareness. You have to balance the two off against each
other.

However, given a choice between flying a VOR or NDB approach
or flying a stand-alone GPS approach in actual, I want the latter
every time.

I don't think I'd disagree with this point. A VOR or NDB approach
with the navaid on the field is fairly accurate near the end (where it
counts), but when the navaid is off the field, the GPS approach should
always be better. I've never flown a GPS T approach (since I don't
have an IFR GPS), but it looks like it would be nice and easy at the
end of a long flight.

My thing with simple wing-leveler autopilots is I'm not sure how
well ours (anyway) would work in really nasty conditions. The sort
of conditions most likely to induce spatial disorientation. Not
dissing it as a safety item at all, just saying I see it more as a
workload-reducer.

The STEC-20 is supposed to be good at handling turbulence. That's
what I'd like to install some day.


All the best,


David