The truth is that sadly the mere mortals that fill up the back of the plane in economy just don;t make the airlines any money on long haul routes, What BA would beed is a full Business cabin everyday, and from MAnchester that won;t happen as he area is not rich enough. Lufthansa does long haul from DUS and MUC because these are huge manufacturing, wealthy areas of Germany. Unfortunately, we are now a service sector ecenomy in the North and that doesnt equal high business class yields.