Portuguese AF Dornier 27 incident.
Military pilot flying Dornier 27 encountered inverted bowl-shaped disc. Sudden drop in plane, despite its characteristic low stalling speed. UFO dark with 4 and white-yellow panels along lower perimeter. EM
One yellow-white dome-shaped object was observed by one male 23-year-old military witness in-flight for six seconds (Rodrigues, Jose Francisco). No sound was heard.