Before he mysteriously disappeared and landed on the Air Force Most Wanted list, Capt. William Howard Hughes Jr. phoned home to tell his mother and father that he was going to the Netherlands.

It was July 17, 1983, and the Air Force was sending Hughes overseas on a mission to help NATO test aircraft surveillance systems. The 33-year-old airman, who worked as a lead surveillance analyst on a base in New Mexico had a top secret security clearance, according to the Air Force Office of Special Investigations.

He told his parents he was supposed to come back from the Netherlands on Aug. 1. But no one ever saw him again.

In the days and weeks after he failed to report for duty at Kirtland, investigators found his car at the Albuquerque International Airport. Inside his townhouse they discovered a to-do list and a list of books Hughes planned to read upon his return.

Finally, they obtained surveillance video that captured him withdrawing more than $28,000 from 19 different banks in the Albuquerque area on July 22. That led investigators to theorize he returned from the Netherlands early and then vanished.

His family feared that he had been abducted. Others speculated that he had defected — possibly to the Soviets — with the highly classified information, a notion that fomented conspiracy theories for years.

His sister, Christine Hughes, maintained that her brother would never defect or disappear without leaving a note, she told Associated Press in 1984. That would be “totally out of character for the Bill we knew,” she said. “We do not feel he disappeared voluntarily.”

As it turns out, it appears to be exactly what Hughes did.

Last week, nearly 35 years after he went missing, the Air Force finally found Hughes living in California under the fictitious name “Barry O’Beirne.” Hughes was arrested at his residence without incident June 6 on charges of desertion, the Air Force Office of Special Investigations announced in a news release Thursday.

The U.S. Department of State’s Diplomatic Security Service caught on to Hughes’s whereabouts, which were not specified, during a passport fraud investigation, leading them to the man named O’Beirne. When investigators confronted him about “inconsistencies about his identity,” the man confessed that his real name was William Howard Hughes Jr. and that he deserted the Air Force in 1983, according to the Office of Special Investigations.

The reason he did this, he said, was because he was “depressed about being in the Air Force” — so he left, created a fictitious identity in California and never came back, investigators said.

In the years after Hughes went missing, a slew of NASA catastrophes, such as the space shuttle Challenger disaster of 1986, as well as the explosion of the Ariane rocket in French Guinea, caused national security commentators to speculate whether the disasters were related and possibly the result of Soviet sabotage. Hughes’s disappearance, in the eyes of some, fit right into the puzzle.

In a 1986 Los Angeles Times commentary titled “Sabotaged Missile Launches?” for example, the former longtime New York Times foreign correspondent Tad Szulc wrote: “The French and American accidents are adding up to a bizarre pattern, surrounded by strange coincidences and unexplained events, deeply preoccupying Western intelligence. These include the apparent defection to the Soviet Union in 1983 of the U.S. Air Force’s leading expert on rocket self-destruct procedures” — meaning Hughes.

Quoting anonymous intelligence sources, Szulc wrote that the intelligence community feared Hughes had either been captured by Soviets or that he voluntarily defected. One such anonymous official said, “He is worth his weight in gold to the Russians in terms of future ‘Star Wars,’ if we have them.”

Upon launching its investigation into Hughes, the Air Force did not immediately rule out defection as a possibility, according to 1984 newspaper accounts in the Albuquerque Journal in which a public affairs officer said it is one “option.” But eventually the Air Force and FBI said it had no evidence indicating any top-secret information had been leaked or that Hughes engaged in espionage. Although Hughes had access to “U.S. Secret and NATO Secret information,” the Air Force maintained that he was not carrying classified information with him on his trip to the Netherlands.

Linda Card, a spokeswoman for the Air Force Office of Special Investigations, told the Albuquerque Journal Sunday that to this day officials still do not have any evidence indicating leaks of classified information. But still, she said, the case remains under investigation.

“Until we have the whole story,” she said, “we don’t have the story.”