Originally Posted by
plhought
It's really simple - with gear down engines run at a higher N1 = better engine response (less spool up etc).
The MD80 has a dial-a-flap system that allows plenty of flap to be selected (between 15 and the setting causing a non-silenceable gear horn...the number escapes me at the moment) keeping N1 up if that's a consideration in this firefighting operation.