Another thing to do, without using fly, is to shoot an arrow at the ghast, and switch to a looting sword. That works as well.
I actually just seen two ghasts flying by one another the other day. I tried to kill them, but they simply vanished….no idea what happened.
For information on applying/how to apply go to: http://www.ecocitycraft.com/wiki/in..._.28Nether-entry.29_Application_-_.2420.2C000 And where you actually apply is: http://www.ecocitycraft.com/forum/forums/applications-builders-resident-nether-aether.21/