The troops are unarmed and wearing civilian clothes, a concession to the Lao government, which gets uneasy with the idea of American military personnel openly moving about inside the country. The conditions are spartan: crisp canvas tents on cement slabs, male and female latrines and showers, and a laundry room.

Lee knows these searches are vitally important. No one in the military can accept the idea of leaving someone behind. He also sees it as part of a pact with troops in years to come, should they need to look for him.

But the searches can be tedious. Lee says his role is to keep his people alert and focused, and the best way is to be enthusiastic from the moment he wakes until he drifts off to sleep. It is in those quiet moments, though, in the dark, when he often wonders if those who vanish here in this isolated world, like the crew of Spooky 21, die afraid that loved ones would never truly know their fate.

He knows that slapping backs and telling jokes, trying to get spirits high for the hours of painstaking labor to come, matter. The slow pace of progress can eat away at your zeal for the work.

When the chopper finally swings over the excavation site on a steep hillside, then lands in the only secure bit of clearing, it’s next to a remote bamboo and thatched hut village. The site is across a deep and swift river. When the searchers first arrived, the only route across was three strands of bamboo the villagers had suspended by vines from a tree.

The angular Lee notes that he might have made it across the old bridge, but the brawnier members of his team would have had trouble, especially carrying the heavy digging tools and coolers of water in the 90-degree heat and swampy humidity.

Their first task was to build a simple bridge, and then they cut a path through a thicket of bamboo and dug 237 steps into the steep hillside, reinforcing each step with a sand tube.

The terrain held perils. The wreckage was hidden by more high bamboo. In its shadows lurked poisonous snakes, bees and jungle leeches. Across the valley on an opposing hillside, villagers spotted a tiger.

Forensic anthropologist Nick Passalacqua has flown in from Hawaii to oversee the actual digging. He’s fairly new to JPAC, but not to searching for lost people. It’s the focus of his year-old doctorate from Michigan State University, and he’s been involved in more than 75 human forensics cases.

“Finding the wreckage is important,” he says. “That doesn’t necessarily mean we’re looking in the right place for the body. But if we find life-support equipment, that means we’re getting closer. Everything is about getting closer to our guy.”

But decades later, flesh and muscle will be long gone. The wind, rain and animals will likely have cleaned and broken bones into shards, and often have moved them elsewhere. The hope is some survival equipment will have moved with any remains. The searchers can never have enough clues.

The team runs a metal detector over the cleared hillside, marking each hit with a red plastic flag. Clicks reveal anything from a wedding ring to bombs and bullets. Each hit is checked out by an explosives expert.

Passalacqua studies the pattern of the wreckage on the hillside because it can possibly tell him something about how the chopper crashed and if it moved afterward. He’s satisfied that in this case, the chopper hasn’t moved much.