"Stubby" wrote in message
...
My old Garmin-12 has room for 500 waypoints. I use it for geocaching
but it should work fine for flying.

I've found that 12-channel parallel units work well in the cockpit of
aircraft that I've flown, but the older ones that could not track as many
satelites or did not track them in parallel tended to have problems during
high bank angles... The Garmin 12 is a 12-channel parallel unit, so I'm not
surprised that it works quite well... Originally, some of the manufacturers
put a speed limit on their units which I assume was to prevent their use in
an aircraft... I have a Magellan 4000 which I still use... At the time, it
was one of few that came with the NEMA output / DC power input connector in
addition to being a 12 channel parallel unit... It still works great as an
input into my laptop, but in standalone mode, it is stuck on a single
screen...

But manually entering waypoints can introduce errors!

Yep... Using the keys on most GPSs to enter waypoints definitely sucks...
Especially if you are trying to do it inflight without an autopilot / wing
leveler... More than once, I've had to take out the trusty AOPA airport
guide and have to enter in lat/long coordinates into the GPS for some some
airport that wasn't in my LORAN database, the identifier had changed, or I
just needed a 3rd reference point as I was skirting the edges of some
airspace... All in all, while flying the plane is not really the time that
you want to have to be looking up stuff on your computer... The least
keystrokes to find a particular piece of information, the better... At one
time, I wrote my own interface to my GPS... It was strictly text based and
as such, could run on a minimal (i.e. *old*) laptop... It had a text file of
all the identifiers of VORs and airports in areas where I normally flew and
it would constantly update the list on screen of the distance and bearing
to/from the nearest 30 or so along with the distance and bearing to my
intended destination, current course, speed, and such... I found it rather
useful when coming back into a Class B airspace in that I could just contact
ATC and say that I was "xxx miles out from the yyy VOR on the zzz radial"...
Unfortunately, like most laptops back then, visibility during bright
sunlight was minimal at best... It was mostly useful for flying at night
since the laptop that I was using also had a dimmer switch on the screen so
that it wouldn't be too bright... Even though I use Street Atlas these days
and tend to draw onto it any airspace with which I might be concerned, I
kind of miss not having that list of VORs and airports nearby...