Captain Mario Lopes has been a United Airlines pilot for 27 years, but there's only one flight that still makes him get a lump in his throat just thinking about it.

Lopes was able to surprise his son, First Lt. Mario Lopes, 25, by serving as a pilot for his flight home on April 14 after he served a nine-month deployment in Kuwait. After his son boarded the plane, Lopes walked up behind him and asked, "First Lieutenant Lopes, what are you doing on my aircraft?'"

The two then shared a long hug, which was captured on video.

"My hairs on the back of my head still stand up thinking about it,'' the elder Lopes told TODAY. "This was a special moment for me. I knew it would be something I would never be able to top or forget."

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Lopes and his wife had gotten word through a military family awareness service that his son might be leaving Kuwait on April 13 to fly to Germany, and then coming back from there to Norfolk, Virginia, the next day.

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United does not fly many military charters, but luckily there was one that was headed to Germany at that time. Lopes' supervisor made sure he would be flying it on the chance it could be his son's flight.

"If I said it was divine intervention, it probably wouldn't be too far off,'' Lopes said.

When Lopes was changing crews in Germany, the captain who piloted the flight there from Kuwait gave Lopes a thumbs-up that his son was on board.

"My crew shielded me as I came in last,'' Lopes said. "I asked him what he was doing on my airplane, and his mouth dropped. When I hugged him, I did not want to let go. It was unbelievable."

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The younger Lopes has been in the U.S. Army for almost three years since graduating from Virginia Tech in 2013.

"For me, it's extremely special,'' Lopes said. "More than a couple friends of mine have told me they've hugged their sons after watching that video. You get caught up in life and you don't realize how precious a moment with a son or daughter is, and you don't realize what you're missing."

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This story was first published on April 29, 2016.