Tackett was last seen in a fourteen-foot skiff near Chichagof Island near the Alaskan panhandle on June 11, 1986. He had departed from Pelican, Alaska earlier in the day with a coworker and a dog. His coworker stated they had been exploring nearby islands before Tackett departed, leaving the companion and dog on a small island. When Tackett didn't return, his friend flagged down a passing boat. Tackett's skiff was located a short time later near Chicago Island, run aground on a sandbar with its motor still in gear. There was no sign of Tackett at the scene and he has never been heard from again. Investigators believed he may have fallen out of his skiff. He was not wearing a life jacket at the time of his disappearance.

Tackett is an accomplished outdoorsman. He resided in Highland County, Ohio in 1986, and had left his home to spend the summer in Alaska. He had planned to get a job on a crab fishing boat, but ended up working at a cannery instead. He was a Boy Scout at the time of his disappearance and a devout Mormon, and he planned to spend his work earnings on future church activities. He vanished three weeks into his trip.

There were several unconfirmed sightings of Tackett in the years following his disappearance. Witnesses may have spotted him in the Alaskan cities of Juneau, Hoona and Sitka. Tackett may also have been seen on Montreal Street and Charles Street in Kingston, Ontario, Canada in March 1998. It's possible he may be suffering from total or partial amnesia. His case remains unsolved.