Body of Secrets: Anatomy of the Ultra-Secret National Security Agency (54 page)

One step
above the U-2 and one step below the Sigint satellites, the bullet-fast SR-71
Blackbird could penetrate hostile territory with impunity. It flew sixteen
miles above the earth, several miles higher than the U-2, at more than 2,000
miles per hour; no missile had a chance against it.

As Major
O'Malley approached the Gulf of Tonkin at a speed of Mach 3.17 and an altitude
of 78,000 feet, the top of his Blackbird was brushing against outer space.
Outside, the air temperature was about minus 65 degrees Fahrenheit, yet the
leading edges of the plane were beginning to glow cherry red at 600 degrees and
the exhaust-gas temperatures exceeded 3,400 degrees. Above 80,000 feet, the
curvature of the earth had a deep purple hue. In the strange daylight darkness
above, stars were permanently visible.

The Comint
and Elint sensor-recorders were already running when O'Malley prepared to coast
in for a "front-door" entry into North Vietnam at two miles a second.
As the Blackbird followed a heading of 284 degrees, the onboard defensive
systems indicated that the North Vietnamese clearly had them in their Fan Song
radar, one of the types used by SA-2 missile batteries. Behind O'Malley,
Captain Ed Payne, the reconnaissance systems officer, flipped a few switches
and the Blackbird's electronic countermeasures prevented the radars from
locking on as they passed over Haiphong harbor near Hanoi.

"The
SR-71 was excellent for 'stimulating' the enemy's electronic environment,"
said retired U.S. Air Force Colonel Richard H. Graham, a former SR-71 pilot.
"Every time [they] flew in a sensitive area, all kinds of radars and other
electronic wizardry were turned on to see if they could find out what was
flying so quickly through their airspace. In fact, our missions were generally
not Elint productive unless 'they' were looking for us with electronic
signals." To capture the signals, the SR-71 used a piece of equipment
known as the electro-magnetic reconnaissance (EMR) system. At first, said
Graham, "the EMR would literally sit there and record signals from hundreds
of miles around the aircraft. It had no discretion on what signals it received,
and made it very difficult to find specific frequencies out of the thousands
recorded on one mission."

But after
an upgrade, known as the EMR Improvement Program (EIP), the SR-71 's Sigint
capability improved considerably. "The EIP continuously recorded signals
from horizon to horizon along our flight path," said Graham, "a
distance of around 1,200 nautical miles. If the system recorded a specific
frequency for a short period of time, computers could plot the precise position
of the transmitter on the ground within approximately one half mile, at a
distance of three hundred miles from the SR-71. . . . The EIP was very
efficient at its job, at times often recording over five hundred emitters on a
single operational sortie. ... It was a Star Wars version of
eavesdropping."

As the
Blackbird entered North Vietnam's "front door," each of its two Pratt
& Whitney J-58 engines was generating as much power as all four of the
enormous engines on the
Queen Mary.
Just twelve minutes after entering,
the Blackbird had crossed the country and was about to exit through the
"back door." Passing over the Red River, O'Malley flicked the Inlet
Guide Vane switches to the "Lockout" position and eased the throttles
out of afterburner. After a second in-flight refueling from a
"boomer"—a tanker—over Thailand, the Blackbird headed back to
Vietnam. This time it passed over the DMZ in search of the heavy guns that had
been assaulting Khe Sanh. In its few minutes over North Vietnam, analysts later
discovered, it located virtually every missile site.

For all
the sophisticated ships, planes, and foreign listening posts, there were many
who fought the Sigint war in the muddy swamps and steamy jungles, right
alongside the combat troops.

"As a
member of the Army Security Agency you will never end up in a war zone,"
the reddish-haired Army recruiter in the neatly creased uniform confidently
assured Dave Parks. "The ASA, because of the high level of security
clearance, is not allowed to serve in a combat zone." That made sense, thought
Parks as he walked out of the Atlanta recruiting station in 1965, having just
signed up for four years.

Two years
later Parks, now an Army intercept operator, arrived in Saigon for a one-year
tour in Vietnam. The recruiter had kept his promise, but Parks had volunteered.
"I wanted to see a war," he said, "and Vietnam was the only one
we had." Assigned to the 303rd Radio Research Unit at Long Binh, near
Saigon, Parks quickly became aware of the dangers involved in the assignment.
"In the event that you are severely wounded would you like your next of
kin notified?" a clerk casually asked him without ever looking up from the
form. "Okay, in the event you are severely wounded do you want the Last
Rites administered? We will need to make arrangements in case of your dying over
here." Finally Parks asked what kind of a unit he was in.
"Infantry," he was told. "A unit called the 199th
Infantry." Parks gulped.

"I
had spent my six months of Advanced Individual Training at Fort Devens being
threatened by the ASA instructors that if we students washed out of the course
we would get a one-way ticket to the 196th Light Infantry," Parks
recalled. "Now here I was eighteen months later being assigned to its
sister unit. This might be more adventure than I'd bargained for. Volunteer for
Vietnam, I should have known better."

Parks's
Sigint unit, the 856th Radio Research Detachment of the 199th Light Infantry
Brigade, was made up of about fifty troops, headquartered at Long Binh.
"Light infantry" meant light and mobile. The troops were equipped
with only the most basic armament, such as rifles, machine guns, and grenade
launchers. The largest caliber of weapon carried in the field was a 90mm
hand-held recoilless rifle.

The men
were housed in a two-story wood-frame barracks surrounded by several layers of
protective sandbags and topped with a corrugated-tin roof. The Sigint
operations compound was encircled by a tall barbed-wire fence with coils of
razor wire on top and to either side. Cover music blared from speakers to hide
escaping signals; loud, rasping generators ran twenty-four hours a day; and
there was a sandbagged guard shack at the only entrance. Intercept operations
were conducted from two windowless vans that were parked backed up to the
building.

Parks,
however, would spend little time in the operations compound. The mission of the
199th in November 1967 was to patrol, with South Vietnamese rangers, the vast
rice bowl known as the Mekong River Delta. Spreading south of Saigon like a
soggy sponge, the area was a maze of swamps, rice paddies, and waterways.
Soldiers called walking in it "wading in oatmeal." In places it was
covered by triple-canopy jungle, sometimes so dense that light had difficulty
getting through. The map gave areas such descriptive names as Parrot's Beak,
the Iron Triangle, and the Rung Sat Special Zone. The 199th's orders were to
seek out and destroy Communist guerrilla infiltrators, mostly from Cambodia,
and to act as a sort of quick reaction force in the event of a firefight.

Operations
were based at Cat Lai, a small village on the banks of the Song Nha Be River, a
winding snake fed by a lacework of muddy canals and narrow streams. Like a
liquid highway, the river carried countless cargo ships to the docks of Saigon,
where they unloaded heavy tractors and foodstuffs and filled up with dusty bags
of rice. As they lined up, bow to stern, waiting for their turn at the docks,
the lightly protected ships were prime targets for the Vietcong, who would
attempt to sink them. It was up to Parks and his fellow troopers to prevent
that.

Unlike
most Sigint soldiers, who worked regular shifts at heavily protected listening
posts, most far from the action, Parks fought side by side with the combat
troops. A bandolier of ammo was strapped over one shoulder, and an M16 hung
from the other. Canteens, poncho, bayonet, camouflage blanket, sleeping bag,
and first-aid kit clung to his back or hung from his web belt. His job, as a DF
operator, was to find the Vietcong before they found his fellow troopers.

Cat Lai
was little more than a few rows of grass huts and some red bougainvillea on the
bank of a muddy river. The troops lived in tents erected over wooden platforms
that served as floors. Two olive-drab vans were used as listening posts, with
two intercept operators in each one. Wooden walkways led to a club, constructed
out of plywood, that served Vietnamese "33" beer and mixed drinks. A
short way down the road, alongside the river at the edge of the village, was an
open-sided restaurant/bar/whorehouse patronized by the crews from ships lining
the waterway. Like the small, rusty tubs anchored nearby, the crews came from
every part of the world and the background conversations had a musical quality.
Years later, when Parks saw the bar scene in the film
Star Wars,
he was
reminded of the club.

The
prostitutes who served the crew also came from many parts of the world. One, a
stunning woman with sparkling eyes and coal-black skin, came from Cameroon in
West Africa. Her ex-lover had recently tossed her off one of the transports.
With halting French and a little German, Parks agreed to a price.

The work
of the direction-finding teams had changed little in the seven years since DF
specialist James Davis became the first American soldier killed in the war. It
had only grown more dangerous. "Being on a DF team was about as far
forward as you could get in the ASA in Vietnam," said Dave Parks. The
Vietcong had shifted their priority targets from the South Vietnamese to the
Americans. In a nearby province, the casualty rate for one American unit was running
40 percent. Out of about forty men, eighteen had been killed or wounded in the
field and another had a grenade dropped on him in the shower.

After a
brief break-in period, Parks was sent out to the front lines, to an area where
Highway 5A slithered out of the Vietcong-infested Delta like a black lizard.
"The whole reason for the infantry being there," said Parks,
"was to act as a checkpoint for the motor traffic coming out of the Delta
headed for Saigon." Parks's weapon would be his DF device, a PRD-1,
simply called the Purd. He kept it hidden from prying eyes, inside an octagonal
tent. "Learning the Purd was not too difficult," Parks said.
"Learning the ins and outs of staying alive was. . . . One learned to
watch where to place each step as you walked, for there were snakes in the
Delta that could kill you in seconds. The snakes of Vietnam were named
according to how far a victim walked before dying from a bite, beginning with
the 'three-pace snake,' the green krait, which had to chew its poison into
you." Before turning in at night, Parks would take his bayonet and see
what might have crawled into his bunk while he was at work. "Lizards
mostly," said Parks, "but sometimes snakes, including the king cobra.
We were in the Delta."

There were
many more rules to live by, according to Parks. "Don't pick up something
without checking it for booby traps. Inside the bunker line, stay on the paths;
outside of it, stay off of them. Don't venture outside the perimeter unless you
were willing to die. Don't walk around at night inside the perimeter for danger
of being shot by your own troops. There was plenty to learn and not much time
to learn it."

On a
typical mission, the PRD-1 would be transported by jeep to what was thought to
be a good spot from which to locate Vietcong in the Delta. Once at the site, a
tactical DF post would be established. A bunker made of double or triple
sandbags would be set up, then encircled with rolls of barbed wire and
concertina wire, perhaps fifteen feet across. A variety of antennas would be
set up and warning signs would be posted. "Signs telling," said
Parks, "that this was a classified site and not to enter on pain of death
and according to some regulation or another." In the center, sitting on a
tripod, would be the PRD-1, which was about eighteen inches square and crowned
with a diamond-shaped antenna that could be rotated. At its base was an azimuth
ring marked off in degrees.

Once he
was set up, the DF operator would put on his earphones and begin listening for
enemy signals. "Time to get on the knobs and kill a Commie for
Mommy," said Parks. In order to cover the operational area, a
"net" of three DF sites would have to be set up. This would allow the
operators to triangulate the enemy signals and get a fix on their exact locations.
" 'Find them, fix them, and fuck 'em over!' was our unofficial
motto," said Parks. " 'Better Living Through Electronics' was another
one."

Once a DF
station picked up an enemy transmission, the operator would take a bearing on
it. The information would then be encrypted and sent up the chain of command
and an attack order would frequently be given. Heavy artillery fire would then
plaster the site, and the infantry would sweep in.

Unfortunately,
the Vietcong were wise to the game; they knew the United States was probably
listening and they avoided transmitting as much as possible. Or they would
place their transmitting antenna up to a mile from the actual transmitter, in
order to avoid fire. "It was a great and intricate game of fox and hounds
played silently between us," said Parks. "Each side aware of the
other though we never met. It was a life-or-death game for them, too. To place
it bluntly, the DF teams were there to aid the 199th in its task of killing
those Vietnamese radio ops and all of their buddies, if at all possible. We
hounded them unmercifully. . . . Their radio ops became worse as time went by
due to the better-trained ones having been killed."