Eric, it's a matter of laying all options on the table. I have found that
GPS_LOG WinCE showed options that I would not have otherwise considered. It
wasn't a mater of not being able to compute (or estimate) all options, but
of being too focused on the flight plan to see them.

An example is a flight where it had become clear that I wasn't getting home
so the task became getting as close as possible, landing at a convienient
airport to reduce the retrieve distance. Playing back the IGC file on
SeeYou with output to the PDA showed that for about two minutes I had a safe
glide to an airport that would have cut the retrieve by 200 miles of
mountain driving. During those two minutes, I was distracted and didn't see
the option. If I had a glide footprint display, it would have been too
obvious to miss.

A moving map with a glide footprint display is very easy to interpret so I
won't miss good alternatives again. I will never fly without it again even
though I own licenses for Glide Navigator II and WinPilot. If I use those,
it will be on a second PDA showing only the data boxes.

A "glide footprint" shows clearly how to cross a mountain range since it
computes glide distance in all directions. The courseline may happen to
cross the range at a high peak so a list type display will show the goal as
unreachable but the "glide footprint" will show that a slight change in
course will easily clear the terrain.

There is also the case where known lift is available in the distance -
perhaps from good clouds or from radio chatter coming from other pilots. If
this area isn't near an airport, list displays aren't useful. With a glide
footprint it's easy to see when the lift is reachable. Then there's
landable terrain that isn't in the airport database. Just knowing that good
landout options are reachable reduces stress and allows the pilot to
concentrate on the task.

It answers at a glance the question of, "Where can I go from right here,
right now at the current McCready setting?" For everyone who has watched a
simulation of a glide footprint display, there's a big "AHA!" moment.

Bill Daniels


"Eric Greenwell" wrote in message
news:SmgIh.11700$ig.1130@trndny01...
An "ide footprint"? That was supposed to be "glide footprint"!


--
Eric Greenwell - Washington State, USA
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