The number of balloons in use varies with the considered needs of the area to be defended. For example, they are used in such large numbers over one of the important industrial regions of Germany that a recent observer reported that they were so thick that he "could see several hundred of them at one glance." Although the statement is undoubtedly far-fetched, it well illustrates the psychological value, aside from the practical value, that balloon barrages have.

According to reports, the German balloon barrage usually forms an irregular belt about five-eighths of a mile wide and about 1 3/4 miles from the outer edge of the target area. There is reputedly anywhere from 200 to 800 yards between the balloons. The balloons are flown at varying heights at different times, the exact height and numbers of balloons flown depending on the time of day, the weather, and the threat of aerial attack.

The purpose of the balloon barrage is to form an irregular pattern of perpendicular steel cables in the vicinity of the defended area, presenting a real as well as a mental hazard to any hostile aviator attempting to fly below the level of the balloons. The net result is to discourage hostile flyers from entering the region of the barrage for dive-bombing tactics against the defended area, and to force the hostile planes to an altitude less favorable for precision bombing. The plan for a barrage is coordinated with light-, medium-, and heavy-caliber gun defense, any gaps in the barrage being covered by light and medium Flak. It should also be noted that in defended areas which include harbors and docks, the balloon barrage may extend out over the water, balloons being suspended from stationary or movable barges.