 Despite its limitations, it is believed to have greatly reduced the chance of a mid-air collision.On some occasions, military aircraft conducting training flights inadvertently collide with civilian aircraft.Before 1958, civilian air traffic controllers guiding civilian flights and military controllers guiding military aircraft were both unaware of the other's aircraft.The 1958 collision between United Airlines Flight 736 and a fighter jet, as well as another U.S. military/civilian crash one month later involving Capital Airlines Flight 300, hastened the signing of the Federal Aviation Act of 1958 into law.