It was a little over eighty years ago that the first "heavier than air" flying machine actually to take off from the ground was built. A few years later, at the beginning of World War l, combat aircraft appeared and added a new dimension to warfare. At first, military aircraft were used simply for spying on the enemy. Very quickly, however , they took on new roles. There were bombing aircraft, aircraft controlling artillery fire, and fighters whose principal job was to attack other aircraft. The latter became very important. as it was so on realized that the side that had control of the air had more chance of winning the battle on land. Aircraft could attack the enemy with bombs and machine guns on the battlefield itself, and also strike directly at the enemy's country. Over the years, more tasks were given to aircraft in war, from patrolling the seas to transporting troops an d supplies.