It is, of course, needed to calibrate the copass when you go to a new flying location, however, what is the approx. distante from previous to be a "new" location? If I fly in one spot, land and walk 200 meter with the I1 is it then in a new location? Probably not, but if I drive 500 meter or 2 kilometer, or 10 kilometer...? Any thoughts on this?