Triangular UFO observed in Hayward, California in 1953

Summary

A 1953 report describes the observation of a yellow triangular object near Hayward, California. A civilian witness used a telescope to see the phenomenon for 3 to 4 minutes. The object was moving slowly but suddenly entered a near-vertical climb and disappeared at high speed. No sound was heard, which confused the investigators. The area had no known military activity or balloons, leading to the conclusion that the object was unidentified.

The description of the object is vague, with no size estimate, but it is mentioned to have a triangular shape with a thin edge compared to its width. No visible exhaust or engine signs were observed. The witness was not very detailed, which complicated the investigation. Despite the clear weather with 9-mile visibility, no further data could be obtained. The report concluded there was no conventional explanation for the phenomenon.