I have not used my Tomtom to navigate in a private aircraft yet (though I am looking forward to getting back into flying again!). In preparation for that day I have practiced using V.O.R's (loaded as POI's), and a piece of 3rd party software called Offroad. Here is the link:
http://www.webazar.org/tomtom/offroad.php?lang=uk
This software (when tweaked properly) will "unsnap" from roads, and work just like a Nav radio (VOR) with an arrow that points right to the VOR (or coordinates you have programed in to some point on the ground, like an airport). Like I said, I have only tried this on the ground so far, but I can't come up with a good reason that it would not work in the air. You will need an external power supply (if the airplane does not have a cigarette lighter installed), because my Tomtom ONE XL will only work for about 1 1/2 hour on its own battery. Here is a link to my solution:
http://www.freewebs.com/randytrent/geocaching.htm
I have planned to use a bicycle handlebar mount that will attach to the yoke (most of those are clamp type) and should not interfere with the forward stroke (I have not verified this yet). The only draw back that I anticipate would be possible interference with the calibration of the aircraft's magnetic compass. I remember having some problems when I placed a "backup" com transceiver on the dash, and the magnet from the speaker caused the magnetic compass to generate incorrect readings. The Tomtom has a speaker (and therefore a magnet) in the back. Depending on how close it is to the compass, this might be a BIG PROBLEM! Be careful !!!!
Here is a link to the VOR's in the United States that have already been configured as POI's for the Tomtom.
http://www.poi-factory.com/node/4720
I like this POI set because if you configure the poi correctly (some manipulation in a CSV file is required), you can get the frequency to display as a phone number of the POI. (handy for when the sectional is hard to read).
I have also loaded these POI's into my Garmin hand held (just in case). The garmin should work just as well (it has the option to unlock from roads built in), but its screen size is significantly smaller, and therefore harder to see. It is a Garmin Etrex Vista HCX hand held unit that I use for geocaching and hiking.
Just as a side note, I found a place to download sectionals:
http://skyvector.com/
These look like one could do a screen capture ((JPEG format) and calibrate the edges to correspond to the correct coordinates. These could then be downloaded into the "Offroad" software as background maps which would display just like a regular Tomtom map. I have done this with Google Earth screen captures, and used them on hiking, and dirt bike (motorcycle) adventures (geocaching too!), and they work really well! I wish it were as easy to get raster format maps into my Garmin!
Good luck,, have fun,, and be safe! Remember, keep your eyes out of the cockpit in VFR conditions!
