Hi Sketco, In addition to what Alan says above, it's been said in the past, that the current and rather long in the tooth, RB will NEVER have a software upgrade that would enable a MLAT function other than with add-ons such as Plane Plotter (not really an RB function then?!), if MLAT is incorporated it would have to be with an entirely new RB MkII - so I hope that clarifies - and I'm certain AN will contradict me and clarify if I'm wrong in this statement!