Well this is my first post, just trying to contribute, so try to be nice...
With that said, lets get to the point:
The quest on Isle of Quel Danas called "The airstrike must continue" is terrible because its long flight route. So i usually tabs out or leave till im at the dead scar. Some times i come back in the middle or too late so i dont get my kills... now here is what you do if you dont kill enough demons...
If you are still in the air on the way back it can be saved, so do this:
quickly log out!
When you log in you should be at the start of the bombing route (not at the start of quest) and can easily get the demons bombed, instead of riding all way back and start all over.
this also works with keeping the enemy at bay