Originally Posted by Diamondeye
When discussing, say, WWII naval battles, we never say that 2 battleships engaged each other with indirect fire. The 2 ships each directly located, aimed, and fired at their enemy once the engagement actually commenced, using either visual means or radar. Their fire was not generally directed at the enemy ship by an outside observer. On the other hand, an observer might very well direct ships firing at shore targets, making it indirect even though the ballistic performance of the projectile was similar in both situations.
Actually, indirect ship-to-ship fire was practised by the USN at least, though I'm unsure if it was ever used in action. Anyway, that's part of the reason why the US liked floatplanes so much and kept them in service until the early fifties.