Why were aircrafts important during the world war 1?

Answer 1

First and foremost, aircraft were used for observation. Detailed photographs could me made, or (using a wireless radio) spot for artillery in real time. Both sides needed a way to prevent this, and there were two ways of preventing enemy aircraft from observing. Air-to-air combat between daring pilots, and concentrated ground fire.

As the war progressed, bombers became more important, capable of carrying ordinance and dropping it with reasonable accuracy: bombers were used to hit railway yards to halt supply, or factories to cut off new material.