Six dark objects move over city in daytime, stop, hover, assume stationary " U" formaiton.Six dark objects appeared to be slowly approaching from the south (from the ocean) coming north (towards downtown) in a group, but not in any identifiable formation about 40 degrees above horizon. Distance indeterminate. Objects were about the size of a B-B held at arm's length. At first I thought they were a group of approaching aircraft as just 5 minutes earlier three bi-planes (flying in echelon formation)had approached from the same direction and area of the sky heading north. However, the six dark objects seemed to stop and hover at about 45 to 50 degrees above the horizon and then assumed (while hovering) a U-shaped fromation. They held that formation and postion for ten to fifteen minutes remaining completely stationary. Then one-by-one the objects moved slowly away from the group to the west about 10 or 15 degrees when they seemed to be obsured by clouds. As the clouds appeared to be of the high altitude variety, I assumed the objects to have been quite large to be visible from that altitude. There were no lights and no sounds. Visiblillity was almost unlimited. Dry weather.