Body of Secrets: Anatomy of the Ultra-Secret National Security Agency (53 page)

Unlike the
other services, the Army had paid little attention to airborne Sigint since the
end of World War II. Throughout the 1950s, Army intercept operators flew
missions in Navy aircraft. The codename of one of their operations in the early
1960s, also aboard a Navy Sky Warrior, seemed to sum up the problem: Farm Team.
It was at that point that the Army decided to invest both manpower and funds in
developing its own professional team of aerial eavesdroppers. By March 1962 the
Army Security Agency had its first airborne DF platform, the RU-6A De Haviland
Beaver, a single-engine aircraft that flew low and slow and had room for very
few operators. Within days, intercept operators in the unit were calling it
TWA: Teeny Weeny Airlines.

Far from
the sleek, high-flying U-2 or the lightning-fast SR-71, the early Sigint planes
in Vietnam were almost comical. "The operators hung a long wire out the
back of the aircraft for a crude direction-finding antenna," said one
veteran. "Crews flew in hot, humid conditions in very loud aircraft.
Missions were often four hours long, but could be longer depending on the
operational tempo of the forces in contact." The planes may have looked
funny, but they provided vital information. "It has been said," the
veteran reported, "that air missions produced as much as one-third of the
intelligence known to ground forces."

Later, a
more advanced aircraft joined the fleet of Beavers. This was the RU-8D
Seminole, a stubby black twin-engine with room for five passengers. Tall thin
blade antennas protruded vertically from the tips of the wings, giving the
diminutive spy plane a somewhat menacing look.

Richard
McCarthy was one of those who volunteered for the 3rd Radio Research Unit's
224th Aviation Battalion. Flying out of Tan Son Nhut Air Base, McCarthy would
often be assigned to the Saigon River Delta area, an inhospitable,
mosquito-ridden wedge of swamp that stretched from Saigon to the sea. Because
it was also the main shipping channel to Saigon, it became a haven for pirates
and small groups of Vietcong guerrilla fighters. "Whoever controlled the
shipping channel controlled Saigon," said McCarthy.

Because
the Delta area was so compact, the single-engine Beaver was preferred. Wedged
behind the copilot, the plane's skin to his back and two Collins 51S1 receivers
in front of him, McCarthy would be listening for enemy communications through
one of his helmet's earphones, and to the Beaver's pilot and copilot through
the other. Navigation consisted of looking out the window for landmarks, and wads
of masking tape were applied to the doors to prevent the plotting sheets from
being sucked out.

Two hours
into one mission over the Delta, McCarthy's earphones began buzzing—the
familiar sound of a guerrilla tuning his transmitter for a call. "He was
good and he was loud," said McCarthy. "It was show time." In an
attempt to locate the guerrilla's transmitter, the pilot would twist and turn
the plane back and forth to obtain different bearings on the target. Once the
enemy forces were plotted, the crew would call in an air strike.

As NSA
began sending more and more airborne eavesdroppers to Vietnam, the sky became
an aviary of strange-looking metal birds hunting for signals to bring back to
their nests. Two miles above the choppers and puddle jumpers was the EC-121M
"Big Look," a Lockheed Super Constellation with monstrous radomes on
its top and bottom. To some, the plane resembled a humpbacked and pregnant
dinosaur. Because it was heavy and the cabin wasn't pressurized, it was limited
to about 10,000 or 12,000 feet. Lined up along the windowless bulkheads, the
intercept operators attempted to squeeze every electron of intelligence out of
the ether during each twelve-hour mission, providing warnings to U.S. attack
aircraft.

Warnings
were critical. In the late spring of 1972, General John Vogt dispatched an
eyes-only message to the Air Force Chief of Staff, General John Ryan, frankly
stating that the 7th Air Force was losing the air war. The problem, Vogt said,
was the increased proficiency of North Vietnamese pilots and their ability to
make single, high-speed passes while firing Atoll missiles. Facing them were
inexperienced U.S. pilots rotating into the combat zone every year.

NSA came
up with Teaball, a system in which detailed warnings based on Sigint were
quickly sent to the pilots. Many at the agency opposed the idea of broadcasting
in the clear such secret information, but the concept was eventually approved.

Teaball
was set up in a van at NSA's large listening post at Nakhon Phanom in northern
Thailand. There, intercept operators would broadcast to the fighters, via a
relay aircraft, the latest Sigint on surface-to-air missile sites and MiG
fighters in their area. When Sigint revealed that a specific U.S. aircraft was
being targeted for destruction, the pilot, nicknamed "Queen for the Day,"
would be instantly notified. "Naturally, that particular flight element
began to sweat profusely," said Doyle Larson, a retired Air Force major
general involved in Teaball, "but all other strike force elements relaxed
a bit and let Teaball take care of them." A veteran pilot and Sigint
officer with over seventy combat missions in Vietnam, Larson said that
"Teaball was an instant success." The kill ratio for American
fighters attacking North Vietnamese MiGs "increased by a factor of
three."

Above the
choppers, the Beavers, the Seminoles, and Big Look were the RC-135 flying
listening posts—Boeing 707s filled with intercept operators and
super-sophisticated eavesdropping equipment. From Kadena, Okinawa, the planes
would fly daily twelve-hour missions, codenamed Burning Candy and Combat Apple,
to the Gulf of Tonkin.

Eventually,
as the war heated up, more and more missions were flown, until an RC-135 was
constantly on station in the northern Tonkin Gulf twenty-four hours a day. It
was an incredibly demanding schedule. Each mission lasted just over nineteen
hours, including twelve over the Gulf. Two missions were flown every day, with
a third aircraft on standby, ready for immediate launch if the primary aircraft
had a problem. All the while, the five RC-135s in the Far East were also needed
to cover the numerous Sino-Soviet targets. The missions took their toll not
only on the crews but on the aircraft, the corrosive salt spray and high
humidity ulcerating the planes' aluminum skin.

The North
Vietnamese air force knew full well the purpose of the aircraft and would
occasionally try to shoot it down. "MiG-21s would streak out over the Gulf
at supersonic speeds and make a pass at the RC-135," said veteran Sigint
officer Bruce Bailey. "Both fuel and fear limited them to only one pass.
They would fire everything they had and run for the safety of their AAA
[anti-aircraft artillery] and SAM [surface-to-air missile] umbrella back
home." Although the RC-135 was a prize target, none was ever lost to a
MiG.

Wherever
they flew, the RC-135s were electronic suction pumps, especially the RC-135C,
nicknamed the "Chipmunk" because of its large cheeklike antennas. The
reconnaissance systems on board were programmed to automatically filter the
ether like kitchen strainers, "covering the electronic spectrum from DC
[direct current] to light," said Bailey. "It had such a broad
coverage and processed so many signals at such an incredible rate it became
known as the ‘vacuum cleaner.' It intercepted all electronic data wherever it
flew, recording the information in both digital and analog format."

At the
same time, the Chipmunk's numerous onboard direction finders were able to
automatically establish the location of each emitter for hundreds of miles.
Sophisticated computers located signals that in any way varied from the norm,
and highlighted them. Other key voice and data frequencies were preprogrammed
into the computer and instantly recorded when detected. "The volume of
data collected by that system was sufficient to require an entire unit and
elaborate equipment to process it," said Bailey. "That large and
impressive operation became known as 'Finder.' The amount of intelligence
coming out of Finder was staggering.

"With
its vacuum cleaner capability and very little specific tasking in the war
zone," said Bailey, "the Chipmunk spent only a couple of hours in the
combat area on those missions. It went in, sucked up all the signals, let the
two high-tech operators look around a little, then resumed its global
tasks."

Still
another RC-135 variation, sent to Vietnam late in the war, was the RC-135U
"Combat Sent," which had distinctive rabbit-ear aerials. It has been
described as "the most elaborate and capable special mission aircraft ever
. . . with technical capabilities that seemed like science fiction."

Still
higher in the thinning layers of atmosphere above Vietnam were the unmanned
drones that could reach altitudes in excess of 12½ miles. "They were
designed to intercept communications of all sorts: radars, data links, and so
forth," said Bruce Bailey. "The intercepted data was then transmitted
to other aircraft, ground sites, or satellites." Based at Bien Hoa Air
Base near Saigon, the diminutive drones contained so many systems as to give
rise to a joke: the Ravens claimed that they also contained "a tiny
replica of a field-grade officer to take the blame for anything that went
awry."

The
program proved very successful. On February 13, 1966, one of the Ryan drones
"made the supreme sacrifice," said Bailey, but in the seconds before
it became a fireball it intercepted and transmitted to an RB-47 critical
information on the SA-2 missile, including the fusing and radar guidance data.
The assistant secretary of the Air Force called it "the most significant
contribution to electronic reconnaissance in the past twenty years."

Above even
the drones flew the U-2, the Dragon Lady of espionage. Following the shootdown
of Francis Gary Powers over the Soviet Union in 1960 and Eisenhower's
declaration that the U.S. would never again overfly Russia, the U-2 had been
reduced to air sampling missions for nuclear-test detection and to peripheral
missions; its glory days were seemingly behind it. Eventually, intelligence
officials began to nickname the plane the "Useless Deuce." The Cuban
missile crisis was only a brief shot in the arm, but after the Gulf of Tonkin
incident in 1964, the U-2 was drafted into service for the Vietnam War.
Although the aircraft started out performing the job it was most famous
for—high-altitude photography—that soon changed. Because of the growing numbers
of SA-2 missile sites—the U-2's weak spot—in North Vietnam, the planes were
soon assigned exclusively to Sigint.

Based
initially in Bien Hoa Air Base near Saigon, and later moved to Thailand, the
U-2s in Indochina were now the responsibility of the Strategic Air Command, not
the CIA. Although happy with the new responsibility, the Air Force pilots found
eavesdropping far more tedious than snapping pictures over hostile territory.
"All I had to do was throw a switch and recorders on board would collect
the bad guy's radar frequencies and signals, and monitor everything," said
former U-2 pilot Buddy Brown. The Armed Forces Courier Service would then ship
the tapes to NSA.

The
missions called for the planes to circle for a dozen or more hours in areas
over the Gulf or Laos, listening primarily to Chinese communications targets.
As more and more antenna blades were stuck to its skin, the once-graceful U-2
was beginning to resemble a porcupine. On board, the receivers were becoming
increasingly automated. All the pilot had to do was to stay awake. The antennas
would pick up the preprogrammed signals, and the onboard receivers would
automatically transmit them down to Sigint analysts in South Vietnam, who could
then retransmit them via satellite in near real time right to NSA. There,
computers and cryptanalysts could immediately begin attacking them.

"The
pilot did not operate the receivers, as they were either automatic or remotely
controlled," recalled Bruce Bailey. "He sat there boring holes in the
sky for hours with very little to do or see. The only relief came from tuning
in on the war, listening to radio calls from strike aircraft and rescue
attempts. That helped keep him awake."

As the
systems became ever more automated, Sigint analysts on the ground were able to
remotely switch from target to target via the U-2's electronics. "Those
systems enabled the specialists to select signals of the most interest,"
said Bailey, "search for suspected emitters, operate the equipment as if
they were aboard the U-2 and to relay their intelligence to users around the
world via satellite and other communications." Eventually, the main thing
keeping the pilots awake, according to Bailey, was simple discomfort.
"Twelve hours is agonizingly long to wear a pressure suit, sit in one
position, endure extremes in heat and cold, control your bowels, and feel your
body dehydrating from the extremely dry air and the oxygen they had to breathe
constantly." Nevertheless, he said, the aircraft's ability to linger in
one area for extended periods, capturing thousands of conversations, made it
"the king of Comint."

"Throttles
to Max A/B," said Air Force Major Jerry O'Malley just before his SR-71 nosed
into the sky over Kadena Air Base. From Okinawa, just after noon on Thursday,
March 21, 1968, the Blackbird set out on its very first operational mission: to
penetrate North Vietnamese airspace, record enemy radar signals, photograph
missile sites, and be back in time for dinner.

As the
Blackbird sped at more than three times the speed of sound toward the hot war
in Vietnam, it left behind a bureaucratic war in Washington. For nearly a
decade the CIA and the Air Force had been secretly at war with each other over
whose aircraft would become America's premier spy plane—the CIA's A-12 or the
Air Force SR-71. They were virtually the same aircraft except that the A-12 was
a single-seater, covert (that is, its very existence was secret), and a bit
smaller and older; and the SR-71 was overt and had room for a pilot and a
reconnaissance systems officer. President Johnson decided to go with the Air
Force version and, eventually, the CIA was forced out of the spy-plane business
entirely.