Robert Donald Linton, 62, and his wife Dagmar were last seen on August 22, 1986, after checking their travel trailer into the Naco West campground in Brinnon, Washington. They unhitched the trailer and left in their gray and white 1982 Dodge Ram pickup for a day of sightseeing; that afternoon was the last confirmed sighting of the couple.

Their pickup was later found abandoned in the Seattle-Tacoma International Airport parking garage, where records show it had been since the day they disappeared. Investigators reported evidence of a violent struggle in the truck, including blood and hair. Forensic testing identified three blood types in the vehicle: Robert’s, Dagmar’s, and a third from an unknown person. The couple’s credit cards were used after they vanished; signatures on receipts matched handwriting linked to Charles Thurman Sinclair, and items bought with the cards were recovered from Sinclair’s storage shed. Sinclair was never charged in the Lintons’ case and died in custody in October 1990.

The Jefferson County Sheriff’s Office lists Robert as an endangered missing person. Does anyone have information about the Lintons’ movements in late August 1986 or recall seeing their pickup at the airport that day?