Help.  recently sold one of the aircraft i flew but it keeps coming to haunt my flight plans.  Cant find a mechanism to to delete it

You don't say what format you're using but try opening the 'Aircraft' folder and deleting the old aircraft. If you then 'Synch with Cloud' you should find all your devices have the same contents. Otherwise simply delete the old aircraft from all the Aircraft folders individually. 

Note that if you don't select a new aircraft as your default machine it's possible that your old one will still haunt your plans.