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Direct bow view of the ill-fated Thresher before she was lost.
OUR ORDERS:
"FIND THE
THRESHER!"
Where is the graveyard of our lost nuclear sub and its 129 victims?
Here, revealing deep-sea detective work never before attempted,
is the stirring sequel to one of the worst disasters of 1963
By Capt. FRANK A.ANDREWS, U. S. N.
as told to lack Ryan
""WW1 ii- .i.iji. i-i v. nynii ji jiiiiiji in I
7Vi bathyscaph dived 1 mie o Snd fA wreckage but was handicapped by limited range and visibility.
Somewhere within a 100-square-mile
area, one-and-a-half miles be
neath the sea, lie fragments of a 250
foot vessel whose fate shocked and sor
rowed the Western world last spring.
Nobody has ever searched for such a relatively
small object at such depths, but that was the job
assigned to the Navy and civilian oceanographers
immediately after the loss of our nuclear subma
rine Thresher with 129 men last April 10.
At 9:13 that morning, Thresher radioed her
tender Skylark: "Experiencing minor problem.
Have positive angle. Attempting to blow" (empty
ballast tanks for surfacing).
From tests and expert testimony, Navy in
vestigators have evolved a theory as to what
caused the Thresher's loss. The salt-water pipi"T
system used to cool nuclear engines sprang a
leak in the aft (engineering) compartment. At
such depths, water rushes in at tremendous pres
sure, even from a minute rupture.
Thresher got in a "positive angle" meaning
an angle suitable for rising and started up. But
flooding very likely shorted the electrical circuits.
Power was lost, and the sub slipped down.
Tests on models indicate that if the aft com
partment collapsed first, then, under pressure, it
became like a bullet and shot into the center
compartment; the forward compartment folded
in like a tin can. All this would happen in less
than two minutes. Thresher then described a
lazy spiral down to the floor, loose debris float
ing around her.
Now it was up to us to find this debris and
then narrow down our hunt until we could ac
tually see the compartments themselves, 8,400
feet below the surface.
After the first month as on-scene commander
of the search, I was beginning to wonder whether
our scientific detection story would ever tell
where Thresher's graveyard was. Four ships had
crisscrossed the area where she had last test
dived and had traced the surface of the sea floor
with sonar; each significant bump on the sonar
graph could be an echo from Thresher wreckage.
The trouble was that eventually we were to get
90 such "blips" so many clues they only further
jumbled our puzzle.
On May 19, 1 was back at base in New London,
Conn., preparing for another go at Thresher's
wreckage. Late in the evening the phone rang.
Art Molloy, a top oceanographer at our analysis
center at the Woods Hole Oceanographic Institu
tion, was on the line: "You'd better get up here
quick. I think we've photographed debris from
Thresher and at Delta."
"Delta" designated one of the sonar soundings
which the Woods Hole experts were almost posi
tive was wreckage. While other ships searched
out new soundings, their vessel Atlantis 11 had
concentrated on "Delta."
If their persistence had paid off, it would mean
we could move closer to the ultimate search
sending down the Navy's bathyscaph Trieste with
trained observers who could study the wreckage
firsthand and take close-up photographs.
Not that we expected the wreckage to prove
what happened to Thresher: the crushing pres
sure of the sea at 8,400 feet would not leave
such evidence. Then why search for it if the
Family Weekly. December IS, ISM