Operation Storm: Japan's Top Secret Submarines and Its Plan to Change the Course of World War II (23 page)

Each bunk hung suspended on chains and could be folded up as necessary.
⁴⁵
The crew’s gear was stored in floor lockers beneath the bottommost bunk.
⁴⁶
“Hot bunking,” or sharing a bed, was also common: when one man was on duty, another man slept in his bunk, and vice versa. Beds were often used as dining tables,
⁴⁷
and the forward crew quarters also had a section for toilets, or heads. The facilities were standard squat-style openings connected to a sanitary tank. Heavy usage and excretory inaccuracy caused by rough seas guaranteed that no one lingered.
⁴⁸
Some sub captains allowed their crew an occasional shower,
⁴⁹
but fresh water was in such short supply that bathing was the first luxury dispensed with once war commenced. Officers were limited to one cup of water per day for washing.
⁵⁰
Some used sake to wipe themselves down,
⁵¹
though it didn’t help much since officers were limited to a single hand towel.
⁵²

NO. 2, 3, 4 COMPARTMENTS (PORT): OFFICERS’ QUARTERS AND WARDROOM
On the port side of the no. 2 compartment was the officers’ galley. Some captains enjoyed special meals, but Nambu tended to waive this privilege.
⁵³
There was also berthing for six warrant officers and space for the hydrophone room. Sound is the most important sense a sub can have below periscope depth. It enables her to locate an enemy or, if she is too noisy, betrays her own position. Sound heads located outside the sub’s hull picked up underwater noise and relayed it to the hydrophone operator. The sea might have been noisy, but an experienced sound man could read it like a book. He could tell the difference between snapping shrimp and the click of a depth-charge detonator. He could even tell whether a ship was approaching or receding, as well as what type it was.

The officer’s wardroom was on the port side, opposite the crew’s quarters. It was capacious compared to that of the
Segundo
and doubled as a dining room or off-duty lounge for the flagship’s officers. The wardroom featured a pair of wooden tables in its center
with bench-style seating and sleeping berths along both sides.
⁵⁴
The berths were double-stacked, sat upon a chest of wooden drawers, and had privacy curtains like a sleeper on a Pullman car. The wardroom also had a fan and was trimmed in wood, most of it varnished—something you’d never find aboard an American sub.
⁵⁵
Part of the officers’ quarters sat next to a bomb magazine though, so not every aspect was luxurious.

Dolls softened the surroundings of many Sixth Fleet subs. The
I-401
had one in her wardroom.
⁵⁶
A demure, white-faced Japanese woman dressed in an exquisite kimono, she was a sentimental item intended to remind the officers of home. Though no Betty Grable pinup, many officers found comfort in her.

Ariizumi’s and Nambu’s cabins were located next to one another near the control room. Both cabins were small with a tiny desk, bed, and hardly enough room to change one’s mind. Nevertheless, they provided the privacy necessary for command.

NO. 4 COMPARTMENT (STARBOARD): CREW’S BERTHING
No. 4 was the last crew compartment in the forward half of the boat. Enlisted men were segregated from their officers aboard Sixth Fleet subs, just as they were in the U.S. Navy. But sealing 200 men inside a cramped combat sub bred an informality that softened differences in rank. Even the dress code was relaxed. An enlisted man’s uniform consisted of a short-sleeved shirt, shorts, socks, rubber-soled shoes, and a short-brimmed cap.
⁵⁷
Just as there was leeway in what U.S. enlisted men wore aboard a fleet boat, the
I-401
’s men exercised similar sartorial discretion. Some went shirtless, limiting themselves to shorts and straw sandals; others wore only a
fundoshi
, or loincloth, when working in the hotter parts of the sub. Officers were more regular in their dress, but the longer the patrol, the quicker they dispensed with formality.

Nothing affected submarine fashion like high temperatures. Some days it was so hot, men slept naked.
⁵⁸
The
I-401
had air conditioning, but South Seas heat easily overwhelmed her cooling plant. Humidity was also a problem. A
Seiran
’s avionics were particularly vulnerable, as was the sub’s electronic equipment. The airplane
hangar was packed with desiccant to reduce humidity,
⁵⁹
but for the men inside the sub, it was a dripping steam bath.

Not much attention was paid to the habitability of Sixth Fleet subs.
⁶⁰
Creature comforts were few, and crews didn’t receive the rest they needed after each mission. Add to this a shortage of trained men, and efficiency declined as the war progressed.

The crew offset their grim industrial setting with a few personal touches. Some of the most popular were Japanese keepsake dolls. Mothers, sisters, and girlfriends made
imon ningyo
for their sons, brothers, and boyfriends to keep them company on their long, lonely voyages. They were a familiar sight in the crew quarters, and it wasn’t unusual to hear a man bid his companion good night before turning in.
⁶¹
At least he knew he wouldn’t die alone.

Sub hygiene was also questionable. Though there was water for brushing teeth,
⁶²
many men chewed gum instead.
⁶³
Most grew beards,
⁶⁴
but haircuts were given to those who wanted them,
⁶⁵
especially since a shaved head helped prevent lice (a constant problem in close confines). Submarine living conditions were undeniably tight. Still, Japanese home life had prepared crews for close quarters and they quickly adapted.

One of a crew’s few personal luxuries was smoking. Favorite brands included
Kinishi, Homare
, and
Cherry
,
⁶⁶
and most men were heavy smokers. Smoking was allowed in many parts of the sub, but cigarettes were in such short supply they were considered a treat.

Another problem affecting the
Sen-toku
subs was rats: it was impossible to keep them off the boats. This wasn’t unusual.
⁶⁷
U.S. subs were plagued by cockroaches. One Sixth Fleet sub set up a rice feeder for their rats; others adopted them as pets.
⁶⁸
Inevitably, there was the odd sailor who trained them for his personal enjoyment. But having rats wasn’t all bad. Sixth Fleet crews often joked, “Safely returning subs have rats. Sinking ones don’t.”
⁶⁹
They had a point.

NO. 5 COMPARTMENT (PORT): CONTROL ROOM
Though relations on a sub could be informal, that didn’t extend to the control room, where only the strictest protocol prevailed. The control room
was the sub’s nerve center. It was where diving, surfacing, and navigation functions were managed as well as where every important environmental system was monitored. Though the conning tower duplicated many of these stations, they were generally limited to combat use.

The
I-401
’s control room was far larger than that of a Balao-class sub. (There was even a head for the convenience of those on duty.) Controls included the hydraulic vent manifold, which flooded a sub’s ballast tanks, enabling it to submerge; the high-pressure blow manifolds, which emptied the ballast tanks of water so the sub could surface; the trim manifolds, which pumped water from one ballast tank to another (or into the sea) to help a submerged sub achieve equilibrium; the air and ventilation systems, which kept the crew breathing; and the main distribution panel, which managed the sub’s electrical supply. The sub’s radio shack, radar room, ship’s office, engineer’s log room, and access to one of its main ammunition scuttles were also located in the compartment. In fact, the only vital systems not found in the control room were the physical propulsion systems, torpedoes, defensive armament, and food prep. Nevertheless, the control room kept close tabs on all of them.

Although a sub’s operating principles were basic in nature, her engineering was not. Every inch of space in the control room was covered by a bewildering array of dials, levers, valve wheels, gauges, meters, circuit breakers, and control knobs. Nothing made sense unless you’d been to sub school. The piping schematic alone would have confounded anyone unfamiliar with sub design. Crew members might have preferred sinking enemy ships, but the truth of sub life was more prosaic; much of their time was spent protecting against the sea’s invasiveness.

BALLAST TANKS
Just as controlling altitude is vital to a plane’s operation, maintaining buoyancy is critical to a sub’s survival. Unsurprisingly, the
I-401
had four types of ballast tanks. The first were the main ballast tanks, which wrapped around the underside of her pressure hull. When a sub wanted to submerge, she filled these tanks with seawater, which entered through flood ports
located near her keel. Once flooded, the tanks grew heavy, pulling her downward. When the sub needed to surface, compressed air was used to blow seawater out through the main vents, increasing her buoyancy.

The main ballast tanks did the heavy lifting of surfacing the boat, but other ballast tanks were necessary for specific maneuvers. For example, when a sub needed to dive in a hurry, the negative tank was flooded. Located underneath the forward part of the sub, it quickly gave the boat the descent angle she needed to dive. The negative tank was especially helpful when the sub was on the surface and had to escape a fast-approaching enemy. In turn, when a sub needed to surface in a hurry, the safety tank was emptied, or “blown.” Located amidships to help maintain the sub’s balance, “blowing the safety” was the fastest way to restore buoyancy in an emergency.

Variable ballast tanks were considered “variable” because they could be used to store either fuel or seawater. This was necessary because when a sub consumed fuel, it lost weight and became more buoyant. To compensate, seawater was pumped into the variable tanks to make up the difference.

Surfacing, submerging, and maintaining equilibrium were three critical tasks that took up much of the control room’s focus. Given their importance, one of the most common expressions aboard a Japanese submarine was “Blow the main tank!”
Blowing
means using compressed air to force water out of the tank, thereby improving buoyancy and allowing the sub to surface. On a somewhat amusing note, Nambu used a Japan-ized version of the order:
“Men tanku burou!”
which was phonetically equivalent to the English.

HELM AND DIVE PLANES
A sub constantly had to switch between the two-dimensional world on the surface and the three-dimensional one below. To help with this, the control room had three “steering” stations. The first was the helm, a large metal wheel used to control the rudder in the stern. The helm directed the forward motion of a sub both when surfaced and submerged. The helm wasn’t enough
for steering underwater, however—a sub required dive planes as well.

The dive planes were two sets of fins located on the outside of the
I-401
’s hull, one set near the bow, the other near her stern. The dive planes enabled her to ascend or descend depending on their angle. When operating on the surface, the
I-401
kept her dive planes rigged in an upward position. She only lowered them to navigate underwater. At first glance, the
I-401
’s bow planes hardly seemed large enough to control the sub,
⁷⁰
but Nambu found them more than adequate.
⁷¹

Two dive planesmen stood side by side at separate steering stations, one controlling the bow, the other the stern. An array of gauges stared them in the face, including a depth gauge, a speed indicator, and a bubble indicator, which showed the boat’s up-or-down angle. An experienced planesman could keep the boat so steady, the sub’s depth gauge never budged an inch.

NAVIGATION
Since the central helm station and master compass were located in the control room, much of the sub’s navigation was done there. It had a small table for manually plotting the sub’s position and tracking enemy targets. Secondary firing solutions were also developed there, to reconfirm those made in the conning tower.

Sub navigation was not very sophisticated during the war. If a sub knew her position within 50 miles of her actual location, it was considered accurate. Celestial navigation was common, and many a navigator scrambled onto a sub’s bridge at night to read the stars. Plotting a sub’s position was as much art as science.

RADAR
The
I-401
carried three different types of radar, all of which had a station in the control room and outlets on the aft part of the sail. The Mark 3 Model 1 air search radar was used to spot planes, while the Mark 2 Model 2 was used to find surface ships. It also had a nondirectional antenna for passive radar detection as well as an omnidirectional antenna, a direction finder, and a target-detection antenna.
⁷²

The principle behind radar was almost magical. The
I-401
would send out a radio wave that “bounced” off an object, like a ship or plane, and returned to the sub, providing the target’s range (distance) and bearing (direction). If the
I-401
tracked the target long enough, it was also possible to deduce its course and speed. The distinctive circular scope and secondhand sweep of light were intended to ensure that the enemy never approached the sub without warning. That was the theory at least. But Japanese radar was still in its infancy and prone to break down. It might have been an improvement over binoculars, especially in poor weather, but it was frequently frustrating.

RADIO ROOM
The radio room, where the
I-401
connected to the outside world, was located on the port side of the control room. It would soon become a favorite place for
Seiran
pilots to loiter while the sub was under way.
⁷³
The communications officer responded to a plethora of messages via shortwave radio—much to Nambu’s annoyance, since he preferred radio silence. Orders from Japan were transmitted at night, when a sub was surfaced, but the
I-401
could also receive messages at periscope depth via a special antenna mounted on her bridge.