Incident Details
According to the pilot, the airplane was at 1,000 feet with an airspeed of about 100 knots, following tower instructions to enter a right downwind for the runway. While approaching the downwind leg, the pilot observed a large black bird and commented to passengers about the need to monitor it for potential maneuvering. Within seconds, the airplane was very close to the bird. The pilot descended, expecting the bird to pass overhead, but the bird dove at the last moment, producing a "thud" on the cabin roof. There were no other immediate indications of impact, and the pilot continued a normal right base, right turn to final, and landing.
Damage Assessment
After returning to his hangar, the pilot discovered substantial damage to the left ruddervator. The damage was not noted during flight; the aircraft performed normally throughout the approach and landing.
Bird Identification
A feather retrieved from the ruddervator impact site was examined whole and microscopically, and was determined to be from a black vulture (Coragyps atratus), an average weight of about 4.7 pounds.