Torpedo problems plagued the fleet submarine throughout much of
the war, but the early years proved to be the most trying time for
sub skippers regarding the ordnance they carried. Malfunctioning
torpedoes were reported by boat captains from the onset of
hostilities and the response from BuOrd was always the same: The
weapons were fine, it was the crew's inabilities that were to
blame. History has proven otherwise.
US fleet submarines went into battle armed with the MK XIV steam
torpedoes which were equipped with the MK VI influence exploder.
The design behind the exploder was to allow the torpedo to
detonate within the magnetic field under the keel of the target
boat, effectively breaking the ship's back. This "top secret"
device was highly regarded by the Navy which believed they
possessed a device that
would revolutionize submarine warfare. In fact, they so tightly
guarded the information about the MK VI that they conducted few
actual tests. I addition, training in its' use was restricted for
fear that the secret about this lethal miracle might leak out.
During the same time the US was tenaciously safeguarding the MK
VI, both Britain and Germany abandoned their use of a similar
devices they had developed due to the equipment's unreliability.
Skippers complained that, after developing an ideal attack setup,
their torpedoes would detonate prematurely, miss completely or not
explode at all. In December of 1941, after having fired in excess
of 70 torpedoes at 28 targets only one hit was recorded. Theories
as to the cause were widespread. The most popular being that the
weapons were running deeper then they were set. Report after
report of potentially faulty torpedoes came down the pike, only to
be officially attributed as "crew error". Resolution to the
problem took its first step forward when in June of 1942 RADM
Charles Lockwood (photo below right), a submarine veteran, was
assigned the command of the Asiatic Fleet. His first order of
business was to test the MK XIV for running depth. His findings
were consistent with the reports from the submarine commanders:
the MK XIV ran deeper then their settings. The skippers were
advised to adjust the running depth accordingly in the hopes of
correcting the defect. Unfortunately, the number of sinkings and
total tonnage scores remained disturbingly lower then expected.
Continuing on the belief that the poor showing was due to
ineffective skippers, many were relieved of their commands,
replaced by younger, more aggressive officers.
If the possibility of conducting a war patrol armed with faulty
torpedoes was not a huge enough problem, the shortage of their
supply, defective or otherwise, was. Political arms limitation
agreements prior to the war restricted the ability of countries to
produce certain weapons. Even with the advent of antisubmarine
technology, submarines themselves were considered to be an
extremely deadly weapon of war, and there was a worldwide effort
to restrict their production. Rules of engagement even set
boundaries as to how a submarine could be employed. The United
States entered WW II with an inadequate supply of torpedoes and
too few facilities to produce the numbers required. The resulting
shortage severely handcuffed skippers during a patrol. By November
of 1942, Pearl Harbor's supply had dwindled down to zero. The Navy
issued guidelines detailing the number or torpedoes that could be
expended on any one target. As a result, many potential targets
By 1943, with the submarine fleet still unable to prove their
overall effectiveness, boat captains were once again casting the
blame for their troubles on faulty ordnance. Patrols returned to
base with tales of torpedoes which would explode about half of the
time. Finally convinced that the MK VI influence exploder was the
culprit, Lockwood ordered them to be disconnected. But the saga of
defective weapons continued. As numerous patrol reports continued
to describe perfect set ups followed by torpedoes striking the
targets but failing to explode, (one account detailed an attack
where 13 out of 15 hits did not detonate) Lockwood ordered new
tests to be conducted. Firing torpedoes at a vertical cliff face,
the duds were closely examined. It was determined the when a
torpedo struck at a 90º degree angle (which was considered ideal)
the firing pin would often become distorted before it could
contact the explosive cap. The results confirmed what many had
feared, that submarines went into battle armed with defective
weapons. Installing a stronger firing pin resolved the issue of
malfunctioning torpedoes virtually overnight. The resulting
dramatic increase in tonnage scores removed any doubt as to the
cause of the problem that bedeviled the submarine fleet during the
first few years of WW II.
U.S. Submarine Fleet - Pacific
Theater - World War II
Gyro Angle -
The angle between the fore-and-aft axis of your own sub and final
track of the torpedo, measured clockwise from the bow of your
Own Course -
The angle between the North-South line and the fore-and-aft axis
of your own boat, measured clockwise from North to your own boat's
- The angle between the North-South line and the fore-and-aft axis
of the target, measured clockwise from North to the target's bow.
Angle on the Bow
- The angle between the fore-and-aft axis of the target and the
Line of Sight (LOS), measured clockwise from the target's bow to
starboard (right) or port (left).
Bearing - The angle between the fore-and-aft axis of your own
sub and and the LOS, measured clockwise from the bow of your boat.
Bearing - The angle between the North-South line and the LOS,
measured clockwise from the North.
Track Angle -
The angle between the fore-and-aft axis of the target and the
torpedo track, measured from the target bow to starboard or port.
Range - The
distance in yards from your periscope to the target.
Torpedo Run -
The distance in yards which the torpedo travels from the tube to
Distance to Track
- The distance in yards from the submarine to the target
track, measured along a line perpendicular to the target track.
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Click for a larger image
AB - Angle on the Bow
C - Target Course
B - True Target
Co - Own Course
Br - Relative Target
G - Gyro Angle