Does 'United 93 was spotted by another aircraft, and, at 10:01, the Command Center advised FAA headquarters that one of the aircraft had seen United 93 waving his wings.' provide a contradiction to the established premise 'Other aircraft saw no visible signs that United 93 was manned.'
United 93 was spotted by another aircraft, and, at 10:01, the Command Center advised FAA headquarters that one of the aircraft had seen United 93 waving his wings.###Other aircraft saw no visible signs that United 93 was manned.