The Predator's two-man team -- a pilot and a camera operator -- was one of the Air Force's most experienced. The pilot, who had flown C-130 cargo planes, switched to drones after 2001 and had spent more than 1,000 hours training other Predator pilots. (The Air Force declined to name the crew or make them available for interviews.)
Also stationed at Creech were the Predator's mission intelligence coordinator and a safety observer.
In addition, a team of "screeners" -- enlisted personnel trained in video analysis -- was on duty at Air Force special operations headquarters in Okaloosa, Fla. They sat in a large room with high-definition televisions showing live feeds from drones flying over Afghanistan. The screeners were sending instant messages to the drone crew, observations that were then relayed by radio to the A-Team.
On the ground, the A-Team was led by an Army captain, a veteran of multiple tours in Afghanistan. Under U.S. military rules, the captain, as the ground force commander, was responsible for deciding whether to order an airstrike.
At 5:14 a.m., six minutes after the two Afghan vehicles flashed their lights, the AC-130 crew asked the A-team what it wanted to do about the suspicious vehicles.
"Roger, ground force commander's intent is to destroy the vehicles and the personnel," came the unit's reply.
To use deadly force, the commander would first have to make a "positive identification" that the adversary was carrying weapons and posed an "imminent threat."
For the next 41/2 hours, the Predator crew and the screeners scrutinized the convoy's every move, looking for evidence to support such a decision.
"We all had it in our head, 'Hey, why do you have 20 military age males at 5 a.m. collecting each other?' " an Army officer involved in the incident would say later. "There can be only one reason, and that's because we've put [U.S. troops] in the area."
The Afghans greeted each other and climbed back into the two vehicles, heading south, in the general direction of Khod.
At 5:15 a.m., the Predator pilot thought he saw a rifle inside one of the vehicles.
"See if you can zoom in on that guy," he told the camera operator. "Is that a ...rifle?"
"Maybe just a warm spot from where he was sitting," the camera operator replied, referring to an image picked up by the infrared camera. "Can't really tell right now, but it does look like an object."
"I was hoping we could make a rifle out," the pilot said. "Never mind."
Soon, a third vehicle, waiting in a walled compound, joined the convoy.
At 5:30 a.m., when the convoy halted briefly, the drone's camera focused on a man emerging from one of the vehicles. He appeared to be carrying something.
"What do these dudes got?" the camera operator said. "Yeah, I think that dude had a rifle."
"I do too," the pilot replied.
But the ground forces unit said the commander needed more information from the drone crew and screeners to establish a "positive identification."
"Sounds like they need more than a possible," the camera operator told the pilot. Seeing the Afghan men jammed into the flat bed of the pickup, he added, "That truck would make a beautiful target."
At 5:37 a.m., the pilot reported that one of the screeners in Florida had spotted one or more children in the group.
"Bull--. Where!?" the camera operator said. "I don't think they have kids out at this hour." He demanded that the screeners freeze the video image of the purported child and email it to him.
"Why didn't he say 'possible' child?" the pilot said. "Why are they so quick to call kids but not to call a rifle."
The camera operator was dubious too. "I really doubt that children call. Man, I really ... hate that," he said. "Well, maybe a teenager. But I haven't seen anything that looked that short."
A few minutes later, the pilot appeared to downplay the screener's observation, alerting the special operations unit to "a possible rifle and two possible children near the SUV."
The special operations unit wanted the drone crew and screeners to keep tracking the vehicles. "Bring them in as close as we can until we also have [attack aircraft] up," the unit's radio operator said. "We want to take out the whole lot of them."
The Predator video was not the only intelligence that morning suggesting that U.S. forces were in danger.
Teams of U.S. military linguists and intelligence personnel with sophisticated eavesdropping equipment were vacuuming up cellphone calls in the area and translating the conversations in real time. For several hours, they had been listening to cellphone chatter in the area that suggested a Taliban unit was assembling for an attack.
"We're receiving ICOM traffic," or intercepted communications, the A-Team radioed the Predator crew. "We believe we may have a high-level Taliban commander."
Neither the identities of those talking nor their precise location was known. But the A-Team and the drone crew took the intercepted conversations as confirmation that there were insurgents in the convoy.