How to use the KML file

You can download the 2012 KML file here:
http://www.mediafire.com/?j1b3i4pcv37d7cj

The Errors file is here:
http://www.mediafire.com/view/?dr3wf27j6safe7o
(though the format is subject to platform)

Once you have the KML file opened in Google Earth you can select the month or months you want - by default it will have the month selected that it was created in.
Then you can adjust the time slider on the main map page to suit your tastes, I would suggest having the left slider all the way to the left, and the right slider all the way to the right - this means that the whole time period for the selected month(s) is being shown.

The next bit is dependant on what you want to use the utility for - but basically you can see which aircraft of the BBMF will be roughly where - obviously their schedule is subject to change at short notice and the flight paths I have deduced have a wide range of error due to a whole range of factors.

Clicking on the name of a particular aircraft brings up it's picture (well it did before the BBMF changed some of them)
Clicking on the title of the KML entry in the places section brings up some info and the warning 'Please bear in mind that flights can be changed or cancelled at short notice' as well as including a link to the BBMF website.

If you select a certain aircraft and then click on the tour button:

You get a virtual tour of what the aircraft will see - pretty neat! :-)

Possible uses include;
Confirming which aircraft it was you have already seen on a particular day,
If you are in a certain location what aircraft you may see,
It will give you an idea of just how busy the BBMF really are,
If you are planning a holiday then you can get an idea of where you might want to visit on certain days.
If you are planning on sitting out in the garden you can check to see if anything is likely to be in the area.

And I'm sure there are other uses that people can find for this interpretation of the published BBMF data.