Back in the late '70s I was a young Marine 1st Lt. going through flight training in lovely Kingsville, TX. During the last stage of training we were given the TA4J Douglas Skyhawk to play with and to learn to drop bombs and shoot the 20mm cannon. It was a delightful aircraft with real speed and power and a roll rate of 720 degrees per second, very responsive to the slightest control input. Back then, smart bombs were just coming on line,but we used dumb bombs and iron sights, a reticle projected onto a glass plate with elevation adjustmnet. A far cry from later radar directed sighting systems and their automatic compenstion for G, speed, etc. You had to consult a rather thick book to get the proper sight setting to match the ballistics of what you dropped or shot with consideration for altitude, airspeed and wind. This in itself caused more than a few humorous errors for some. This particular day we were flying to a practice target for 20mm firing. The targets were large concentric circles laid on the ground with lime and scored by observers. Normally we would go in a flight of four and roll in one at a time to shoot. Just prior to roll in the gun would be armed and then concentration directed to the target and sight. As I rolled in and obtained a steady sight picture and prepared to press the trigger, a Cessna 172 flew right across the center of the target. Be careful out there and stay out of Restricted areas unless you are talking to the area controllers.