Interestingly enough Scottish Avoation. At the time of developing PIK as a major training airfield also owned an airfield at Grangemouth and this was planned and marketed as Central Scotland Airport. Not sure exactly why it never happened but I'm sure weather (fog) was one if the reasons cited. I think you can forget (however sensible it seems) a mew central airport. It would mean fewer services, less competition, higher fares and probably fewer jobs. We have great choice across the central belt and three good airports to choose from. We should be trying to ensure we maximise their use.