Alder Lake, WA triangular or delta-shaped object report — March 7, 1987

On March 7, 1987, at 7:30 p.m., at Alder Lake, WA, Washington, United States, witnesses reported the following: 2 observer(s). Silent manta-delta/triangle/box-like craft going toward overhead. Paces truck / 3 minute(s). Sails away over hills.