We were off again at dawn, cruising at 11,500 feet in clear, cool, motionless morning air. A few convective buildups lifted themselves before us like awakening sentinels as we reached Wisconsin; we slipped unseen between their sunlit towers. As we loafed the last 30 miles along the railroad track from Ripon at 90 knots under a low overcast, unseen controllers below issued a steady patter of instructions-White low-wing, waggle your wings! Green biplane, switch to tower frequency now!-while occasional airplanes materialized suddenly from the fog and flitted past in the opposite direction. The traffic at Oshkosh, with innumerable airplanes simultaneously landing and taking off at intervals of a few seconds, reminded me of the digitally enhanced swarms of Japanese attackers in Pearl Harbor. The tower controller remained jovial and polite, however, congratulating each pilot on a tight turn to final and wishing all a happy show.