Body of Secrets: Anatomy of the Ultra-Secret National Security Agency (28 page)

A month
before, late at night on August 17, Cassidy had reported to a basement office
in NSA's Operations Building for a Top Secret codeword briefing on his new
assignment. "One of our missions," recalled the former Elint
intercept operator, "was to bring back any rocket telemetry that we could
get." At the time, the White House was very concerned about advances in
Soviet ballistic missile capabilities. An over-the-pole attack launched from
one of the ICBM bases close to the Barents Sea was the most likely scenario for
World War III. U.S. Sigint aircraft would occasionally fly into the area in an
attempt to collect signals, but their presence was immediately obvious and
sensitive activities would be halted until it departed. The only way to capture
the telemetry—key signals revealing the operational performance of the missile
that were transmitted back to its control center—was by stealth. A submarine
would have to penetrate deep into Soviet territorial waters in perhaps the most
dangerous sea on the planet.

To hide
the true nature of their mission, even from the crew, Cassidy and the three
other intercept operators were given "radiomen" patches for their
uniforms. Their orders never even mentioned the name of the ship they were
being assigned to. It simply used the words "U.S.S.
Classified."
The
U.S.S.
Classified
turned out to be a twenty-year-old diesel submarine
named the USS
Halfbeak,
which was berthed at the naval base in New
London, Connecticut. Although outwardly like any other sub, eavesdropping
antennas had been attached to the
Halfbeak's
electronic countermeasures
(ECM) mast, and a special receiver had been installed in the periscope well
beneath the conning tower.

The intercept
operators, not being part of the regular crew, were squeezed in wherever there
was space. "I lived in the forward torpedo room, among eighteen torpedoes
and six torpedo tubes," said Cassidy. His bed was a piece of plywood
sandwiched between Mark 24 wire-guided torpedoes—each with 500 pounds of
explosives packed into its warhead. Nearby were two Mark 45 nuclear-tipped
torpedoes with tags labeled "War Shot."

It was
late September when the
Halfbeak
finally reached its operational area
off Russia's Kola Peninsula. Inside the crowded metal tube, life was cold,
dirty, and quiet. To ensure radio silence, tubes had been removed from the
communications equipment and locked in a safe. Adding to the discomfort, one of
two stills that converted salt water into freshwater had broken down. Thus,
each man was given a large tomato soup can to fill with water once a day for
washing. Then about half the heaters quit. "I remember lying in my bunk
scraping the frost off the torpedo above me," recalled Cassidy.

Despite the
problems, the mission went on. Beneath the black, crawling waves the
Halfbeak
slowly maneuvered toward its target, a heavily protected island off the
Russian coast where much of the Soviet missile testing was taking place. During
the day, the sub operated on battery power, cruising quietly at periscope depth
sixty-two feet below the surface. Once the passive sonar indicated that no
surface contacts were above, the mast with the Sigint equipment would be raised
about six feet above the waves.

"If
it was daylight, we would be running fairly slow so it wouldn't make a
wake," said Cassidy, "because if you went over four knots underwater,
this would start throwing up a plume." At night the diesel engine would be
fired up and the snorkel mast would be raised to provide fresh air to the crew
and to charge the batteries. Ever closer the sub approached—well past the
twelve-mile territorial limit and just a few miles off the beach. Through the
periscope, the men could see beefy Russian women hanging out laundry.

Down in
the makeshift Sigint spaces, behind a closed door in the control room, the
intercept operators listened like electronic bird-watchers for telltale sounds.
They attempted to separate the important signals—the wobbling, squeaking,
chirping sounds that reveal key radar and telemetry systems—from a cacophony of
static. "We used to practice all the time listening to tapes of different
Soviet radar," said Cassidy. "So if we heard it, we could tell what
it was. Before we would go on a mission, we would train ourselves by sitting in
front of these tapes that operators had made while out on patrol." At the
same time, they measured and photographed the squiggly electronic waves that
rippled across the orange screens of the Elint receivers.

"We
had special equipment that was made up of eight to twelve little receivers that
would each receive a frequency that the Soviets transmitted telemetry on,"
recalled Cassidy. "On this run the main interest was the telemetry. But
any Russian signal you were able to tape was good because all this went into a
database. . . . And this would all be piped into a recorder, so whenever we
heard telemetry coming from the island, we would start to record it. The
rockets could be anything from satellite launches to missiles. We heard a lot
of fire control radar along with it. We had capabilities of intercepting twelve
to fourteen channels." To capture Soviet voice communications, one of the
intercept operators was a Russian linguist.

The
greatest worry was discovery. Thus, great care was taken to watch and listen
for any approaching Soviet aircraft, ship, or submarine.

For weeks
all went well despite the
Halfbeak's
risky location. But early on a dark
morning in late October, Cassidy heard the distinctive whistle of a
"mushroom" radar, indicating that somewhere overhead was an
approaching Soviet TU-95 Bear—a large and deadly strategic bomber with swept
wings and four huge turboprop engines. At almost the same moment, he also picked
up the signal of a Russian destroyer bearing down on the
Halfbeak's
location.
"I have contact!" Cassidy yelled to the captain. "Very weak
TU-95 aircraft mushroom radar and a Soviet surface ship."

The
troubles only got worse. "And then I heard this
whish,"
Cassidy
recalled, "and I knew it was a flat-spin radar from a Soviet
"Foxtrot"- or "Whiskey"-class submarine. After I told the
captain, we pulled all the antennas and masts down. This was at night—early in
the morning. We were snorkeling, which means we had the diesel engines running.
We went to Battery Operation and then to Battle Stations Torpedo. We pulled the
plug—it went down. We knew we had in the air at least one Soviet aircraft. We
knew we had at least one Soviet destroyer and very possibly a Soviet conventional
submarine out there."

The
captain took the
Halfbeak
deep—about three hundred feet— and managed to
hide under a dense layer of salt water that deflected any enemy sonar signals.
Sailing at four knots, the boat headed south out of harm's way. By afternoon,
with the danger apparently over, the
Halfbeak
headed back toward its
operational area near the missile-testing island, arriving early the next
morning. But now there was a new problem: through the periscope, as it was
rising toward the surface, the captain noticed something strange. Everywhere he
looked, all he could see were thick logs floating above. Sigint was out of the
question. "We couldn't really put the ECM mast up in that stuff because it
had these little thin antennas sticking out, and if you hit that with a log . .
. it's going to ruin the watertight integrity of the antenna," recalled
Cassidy. He suspected that the Russians had dumped the wood deliberately in
order to hinder the sub's spying.

Determined
to continue the mission, the captain sailed the
Half-beak
to another
part of the island's coastline and raised the camouflaged ECM mast containing
the eavesdropping antennas. By then, however, the Russians were aggressively
searching for the intruder and once again, late in the afternoon, Cassidy heard
the ominous sounds. This time it was two Soviet destroyers and the signal was
Strength Five—the highest, meaning the destroyers were almost on top of them.
"I have two Strength Five Russian waterborne platform emissions!"
Cassidy yelled to the captain. Then sonar reported the presence of another sub
nearby. The captain immediately ordered a dive and set Battle Stations Torpedo.
Through a small side tube, a number of white, four-inch pills were fired into
the water. Like giant Alka-Seltzer tablets, they were designed to create clouds
of bubbles to hide the escaping sub. "We must have fired twenty of
those," recalled Cassidy. "We used that and prayed."

In the
control room Cassidy could clearly see the depth gauge about four feet away. It
had a red mark at 350 feet, indicating the test depth—the safety limit for the
sub. To his horror, the needle slipped past the mark and continued downward as
the old boat began to squeak and groan. "Are we supposed to go below 350
feet?" he yelled to the sailor at the controls.

"We
do whatever the old man says," the man yelled back.

"Oh
God," Cassidy suddenly yelled. "We're sinking. The water's coming
in!" Above him he heard a "pop" and ice-cold water poured down
on his head. Luckily it was only the snorkel drain breaking, releasing about
five gallons of water that had accumulated in the tube.

As the sub
continued to descend to about 400 feet, a short distance from the muddy
seafloor, the sonar men could hear pinging sounds from the Soviet ships
searching for them above. Next the captain ordered Sedge Quiet. "This is
where you basically shut off everything except for the gyroscope and the
electric motor that's turning the shaft," said Cassidy. "Lights were
reduced, heating was off, the galley ranges were off, hydraulics were
off." With the hydraulic system inoperative, it took two sailors to steer
the sub, using small handles that pop out of the wheel.

Hour after
hour after hour the
Halfbeak
quietly maneuvered deep in the Barents Sea
as sonar continued to pick up a heavy presence on the surface. At one point a
sonar man heard what he thought was an explosion from a depth charge. Crew
members were ordered to remove their shoes to keep down the noise. "We
were warned about banging anything, coffee cups," said Cassidy. "No
noise at all. It was like a tomb in there."

Eventually
the oily air began turning thin and rancid. The captain passed the word to
break out the carbon dioxide absorbent—cans of powder would be spread on bunks
to help draw the deadly gas from the air. Nevertheless, the sub's doctor warned
that the oxygen levels were becoming dangerously low. Sailors, including
Cassidy, passed out and had to be revived. Two large oxygen canisters were
placed in the central part of the sub, and it was suggested that those who felt
faint should take a few deep breaths from the masks attached.

Without
electric power, all that the galley could come up with was peanut butter,
crackers, and Kool-Aid, but few had the strength to go there anyway. "It
was so hard to breathe, you didn't even want to walk from the forward torpedo
room to the galley, which was probably about one hundred feet," recalled
Cassidy. "Because it was too much effort, you had a hard time breathing.
And it was cold; it was damp. They were holding us down. We could not surface
because they were above us. Sonar could hear their engines. There were four
separate surface contacts around us, plus a probable submarine."

Finally,
after about twelve or thirteen hours, the pinging began to cease. After another
hour, to make sure that the Soviet ships had departed, the
Halfbeak
slowly
began to rise. "He said you know we could probably surface now, but we are
going to take another hour and I want you to just search and search and listen,
listen, listen," said Cassidy. "And they would put a new operator on
about every fifteen or twenty minutes for another good set of ears. When they
were positive that there were no surface contacts around, we just squeaked up.
I searched all the bands for aircraft . . . and when the captain and the exec
[executive officer] were as sure as anybody could be that there were no signals
up there, we came up to periscope depth. This was early morning. Looked around
with the attack scope and the regular scope and saw nothing. And once they were
happy with that, they put up the snorkel mast. . . . The first time we
snorkeled after being down so long, the fresh air was so clean and pure it hurt
you, it actually hurt your lungs."

With most
of the mission completed and the Soviets hot on their trail, the captain
decided to head back to New London. There, the dozens of intercept tapes were
double-wrapped and sent by courier to NSA for analysis. As with most missions,
the intercept operators were never informed what the agency learned as a result
of the dangerous mission. They did not have the required "need to
know." And in the ship's history of the USS
Halfbeak,
the year 1965
has been eliminated.

Throughout
the Cold War, similar missions continued. Even as late as 2000, the Barents Sea
remained prime eavesdropping territory for American submarines. That summer,
the bullet-shaped bow of the USS
Memphis,
a 6,000-ton attack sub,
slipped quietly out of its home port of Groton, Connecticut, and disappeared
beneath the frosty whitecaps of the Atlantic. Its target was a major naval
exercise by the Russian Northern Fleet—the largest such exercise in a decade.
Among the fifty warships and submarines participating in the mock battle was a
steel leviathan named the
Kursk,
a double-hulled, nuclear-powered
submarine twice the length of a Boeing 747. On board were about two dozen
Granit sea-skimming cruise missiles as well as torpedoes. It was the pride of
the nation—the most modern submarine in the Russian Navy.