Black UFO seen in Alaska in 1947

Summary

A pilot and co-pilot reported a black disc-shaped object, larger than a C-54, flying at low altitude near Bethel, Alaska. The incident occurred at sunset on August 4, 1947, when the observers followed the object for four minutes. It was estimated to travel at 520 mph, three times the speed of their aircraft. Although initially thought to be a conventional plane, its size and lack of engines confused them. The official report suggested they might have been deceived by perspective and sunset light, but the pilot's credible reputation adds weight to the sighting. This document is part of the declassified Project Grudge files, which sought conventional explanations for UFO sightings.