"He's not squawking," says Air Force Lt. Col. Bryan Dickson, the commander, meaning the plane was not broadcasting the standard signal to air traffic controllers. "Anyone not squawking is suspect."
During the 12-hour flight aboard an E-3 Sentry Airborne Warning and Control System, or AWACS, the crew would engage in a high-tech chase, illustrating the extensive military resources the U.S. and its allies are using against drug traffickers.
But it also showed just how much the odds still favor the smugglers.
The flight came with conditions. Under military rules, it was forbidden to reveal many details, from the size of the crew to the color and shape of symbols on radar screens that looked like old-school video games. The secrecy was intended to avoid tipping off traffickers, as well as anyone else interested in American military capabilities.
The flight took off Saturday night from Curacao, an island about 30 miles north of Venezuela, where the U.S. keeps military planes and personnel, and required a mid-air refueling.
Though it stayed in the air long enough to reach Alaska, the plane never left the Caribbean as the crew undertook the challenge of trying to identify suspicious planes among the dozens of aircraft cruising the skies. Air Force crews also monitor boats, an even tougher task given the traffic in the region.
Among the details shrouded in secrecy was how the E-3 crew knew to look for the plane from Venezuela. The order came from the U.S. military's anti-drug command center in Key West, Fla., said Air Force Capt. Kim McClain, a senior crew member. But the source of that tip was a secret.
As they watched the plane, the crew found more grounds for suspicion.
The military also dispatched a Navy plane to check the tail number, which turned out to be fake.
Next, another plane - from a country that can't be disclosed - was sent out to tail the suspect. That plane eventually turned back, and the E-3 was again the lone tracker, flying within 60 miles of the suspicious aircraft at one point before slowing down to avoid overtaking it.
Little was known about the suspect plane, but military officials had a good idea what it was up to.
About 20 percent of cocaine is shipped by air - a more expensive method than by sea - and the planes can only carry about 1,000 pounds at a time, Coast Guard Rear Adm. Nimmich said in an interview before the flight.
About 90 percent of drug flights take off from Venezuela, carrying cocaine mostly produced in neighboring Colombia, a close U.S. ally. U.S. authorities accuse the government of President Hugo Chavez of not cooperating in the fight against drug traffickers, an accusation the Venezuelans deny.
The airborne surveillance crews track about 600 flights and 100 ships a month. So far this year, the U.S. and its allies have seized 229 tons of cocaine, five tons of marijuana and 166,000 grams of heroin in Latin America and the Caribbean, with a total street value of $4.1 billion, the military says.
But success is rare.
U.S. and allied nations manage to coordinate the military and civilian law enforcement necessary to catch drug runners only about 5 percent of the time. In a place like Haiti, a frequent destination, there is virtually nothing that can be done once the plane lands because the impoverished country has so few resources to respond, the admiral said.
"We're lucky we get 5 percent," Nimmich said. "Everything has to come together perfectly."
On this night, there was some hope as the plane approached Honduras. Two Navy planes were scrambled to follow it - from yet another country that cannot be disclosed.
Their part of the mission completed, the E-3 surveillance crew broke away from tailing the suspect plane and went off to look for other suspicious aircraft. If the crew members knew what happened to the Venezuelan flight, they didn't say.
"Eventually, we are going to catch up with them," says McClain, a reservist from Rockford, Ill.
Not this time, though. Once on the ground, the task force revealed the smugglers landed and unloaded before police could get to the scene. They wouldn't say what country the plane touched down in or how the drug runners escaped - only that they got away.