Definitely the most important part of the golf swing is the impact. The backswing, turning of the shoulders, unwinding, and all the other parts of the swing are enablers to a good impact. Hitting down on the ball is key with irons. Because the impact occurs in a fraction of a second, hands-eye coordination is impossible. The swing happens and the ball is just in the path of the club face. However, you can train your body to produce a swing that hits down on the ball, using a very good drill. You can do it in the driving range or in a practice round. And you don’t need any expensive gear or sophisticated mechanical aid. You only need those broken tees you find on the tee areas. Put the broken tee about 6-8 inches in front of the ball and try to hit the ball and the broken tee at once. I guarantee you that this will improve the impact and enable a very good contact, that will make the ball airborne all the time.
Here is a video that shows you how to do it: crisp contact