“Without the Ho Chi Minh Trail,” said military historian James Willbanks, “the war doesn’t go on.”

The morning it disappeared, Spooky 21 roared west toward Laos, passing peaks crowned by tall trees and valley floors cut by fast rivers, covered in rice paddies or choked with bamboo. Villagers moved up and down the knife-sharp slopes with ease. But the heavy tree cover made it a hell of a place to find and fight an enemy.

The mission

The plan was for the crew to find and destroy its target — a way station hidden beneath the thick foliage, typically home to ammunition depots and anti-aircraft batteries. They were expected back at Da Nang about 1:30 p.m.

But on a clear morning, like that Christmas Eve day, gunners hidden beneath the jungle leaves could spot a big fat target like Spooky etched against the blue sky long before the crew could see them.

Most Laotian villagers had fled the region to escape the war. But they weren’t the problem. It was the North Vietnamese moving along the trail, and the Ho Chi Minh Trail had never been busier.

By 1965, the U.S. military resolved to do something about it. Bomb one path and the North Vietnamese army’s Group 559 — a military team strung along the trail like a version of Pony Express way stations, and tasked with keeping it open — simply redirected traffic several hundred yards over to a similarly primitive route while it patched up the first one.

But the trail ran through Laos and Cambodia, and cutting it in half would have meant expanding the Vietnam War into a regional war. Closing it would have required an invading and occupying ground force, a prospect that had little appeal.

The U.S. was stepping on the gas, however, as far as expanding its presence in South Vietnam. The 23,000 troops stationed there in 1964 had risen to 185,000 by the end of 1965, when Spooky 21 left Da Nang. The number would continue to climb until it peaked in 1968 at more than half a million.

But as the number of American troops increased, so did Soviet and Chinese support for the North Vietnamese. The American air campaign wasn’t enough to stop the flow of weapons, ammo — even food — often stacked onto comically overloaded bikes or stuffed into baskets and lashed to donkeys, sometimes even to elephants.

Desperate for a more accurate and lasting way than bombing to hit and continue hitting a target, the old workhorse C-47 cargo plane had been outfitted with three electric miniguns, bolted to the floor and pointed out holes where windows had been.

Gunner plane

After a year of tests, the plane was in its first month as a response to the increased activity on the trail. “Spooky” was its call signal, a homage to its ability to break Viet Cong night attacks on American bases.

But among the enemy, its nickname was “Dragon.” Tracer rounds, especially at night, made it look like the propeller-drive plane was spitting fire at the ground.

Jeffords controlled the aim of Spooky’s guns from the pilot’s seat. In the plane’s belly, Hassenger helped make sure the ammo didn’t jam. The only blond in an otherwise brown-haired group of airmen, his job was simple: Once they started raining fire on the enemy, the fire didn’t stop.

Hassenger had volunteered for the job because he thought it was the future. Also, his family could use the combat pay. His wife, Sherrie, said that her husband was a military man and made for his role.