I recently found this great article from Air and Space magazine, well worth your time… -Jack
BLACK HELICOPTERS ARE A FAVORITE FANTASY when conspiracy theorists and movie directors conjure a government gone bad, but in fact, the last vehicle a secret organization would choose for a stealthy mission is a helicopter. A helicopter is a one-man band, its turbine exhaust blaring a piercing whine, the fuselage skin’s vibration rumbling like a drum, the tail rotor rasping like a buzzsaw.
In the last dark nights of the Vietnam War, however, a secret government organization did use a helicopter for a single, sneaky mission. But it was no ordinary aircraft. The helicopter, a limited-edition model from the Aircraft Division of Hughes Tool Company, was modified to be stealthy. It was called the Quiet One—also known as the Hughes 500P, the “P” standing for Penetrator.
Just how quiet was the Quiet One? “It was absolutely amazing just how quiet those copters were,” recalls Don Stephens, who managed the Quiet One’s secret base in Laos for the CIA. “I’d stand on the [landing pad] and try to figure out the first time I could hear it and which direction it was coming from. I couldn’t place it until it was one or two hundred yards away.” Says Rod Taylor, who served as project engineer for Hughes, “There is no helicopter today that is as quiet.”
The Quiet One grew out of the Hughes 500 helicopter, known to aviators in Vietnam as the OH-6A “Loach,” after LOH, an abbreviation for “light observation helicopter.” The new version started with a small research-and-development contract from the Advanced Research Projects Agency (now the Defense Advanced Research Projects Agency) in 1968. The idea of using hushed helicopters in Southeast Asia came from the CIA’s Special Operations Division Air Branch, which wanted them to quietly drop off and pick up agents in enemy territory. The CIA bought and then handed over two of the top-secret helicopters to a firm—by all appearances, civilian—called Air America. Formed in 1959 from assets of previous front companies, Air America was throughout its life beholden to the CIA, the Department of State, and the Pentagon.
The Quiet One’s single, secret mission, conducted on December 5 and 6, 1972, fell outside Air America’s normal operations. The company’s public face—what spies might call its “legend”—was that of a plucky charter airline delivering food and supplies to civilians in Laos, and flying occasional combat evacuation missions in Laos and South Vietnam. While it did substantially more than that, and at considerable peril (217 of its employees died in Laos), Air America crews did not make it a practice to fly deep into North Vietnam.
The mission was intended to fill an information gap that had been galling Henry Kissinger, secretary of state under President Richard Nixon. Negotiations to end the 11-year war had begun in March 1972 but stalled in part because South Vietnamese leaders feared that North Vietnam would invade not long after U.S. troops left. A five-month Air Force and Navy bombing campaign called Operation Linebacker had brought the North Vietnamese to the negotiating table in Paris that October, but even that campaign could not force a deal. Kissinger wanted the CIA to find out whether the North Vietnamese were following the peace terms or just using them as a smokescreen for attack plans.
From its intelligence work a year earlier, the CIA knew about a weak point in the North Vietnamese wall of security: a telephone line used by the country’s military commanders, located near the industrial city of Vinh. A patrolled bicycle path ran alongside the string of telephone poles, but at one spot, about 15 miles southwest of Vinh and just east of the Cau River, the phone line went straight up a bluff, over a ridge, and down the other side. The terrain was too steep for bikes, so the path followed the river, which flowed around the bluff, rejoining the telephone poles on the bluff’s far side (see hand-drawn map, p. 67). This would be the best place to drop off commandos to place a wiretap.