Around the World Submerged: The Voyage of the Triton

During the sealed-ship test we had replenished our oxygen in two ways. First, there were the oxygen banks—great steel cylinders in which pure oxygen was stored under high pressure. Located external to Triton’s pressure hull, in the ballast tanks, they were piped to manifolds forward and aft where we could automatically control the rate of revitalization as the pressure in the banks dwindled.

Our second revitalization system made use of a device borrowed from miners, who had for years employed “oxygen candles” as an emergency oxygen source. Our “candles” were much larger than the miners’, but they were made of the same materials and were handled in a very similar manner. Under average conditions, we burned them in a specially designed oxygen furnace at the rate of two per hour, though as previously mentioned, this rate had to be increased on Fridays. Each “candle,” when exhausted, produced a large, heavy iron klinker, which in due course found its way to the garbage ejector.

The greatest problem in sealed operations, however, did not lie in maintaining the requisite oxygen content in our ship’s internal atmosphere. It was a matter of retaining the atmosphere itself, and this was a problem that remained with us the whole cruise.

To understand this, it must first be appreciated that many of a submarine’s mechanisms are operated by compressed air. After it is used, the air simply passes into the interior of the ship, where it becomes part of the ship’s internal atmosphere. During the first weeks of the cruise, therefore, the pressure built up slowly during the day and was suddenly vented off every night, when we extended our ventilation pipe to the surface and opened its cap. We discovered immediately that running all the air compressors at maximum capacity during the time we were renewing our atmosphere from outside was not enough to recharge as much air into our air banks as had been used. We were, in effect, slowly losing air. To combat this, we resorted to starting the air compressors well before raising our snorkel pipe, thus pumping the precious air back into the high-pressure air banks instead of belching it out when we opened the snorkel-head valve. This had the incidental disadvantage of increasing our “low-oxygen” symptoms and increasing the time we suffered from oxygen deficiency, but, worse, we still were not able to recharge as much air as we had used during the day.

Every night a check of the air banks showed that the maximum air-bank pressure we reached on charge was slightly less than it had been the previous night. Without compressed air a submarine cannot operate, a fact which had lain in my consciousness ever since depth charges had so damaged both of Trigger’s air compressors that it looked as if neither could be made to run again.

In Triton’s case, barring a breakdown of our compressors, we could solve the problem by merely leaving the snorkel up longer and waiting until the compressors had been able to retrieve their position. But to do so would require a sacrifice of speed of advance, since neither periscope nor snorkel tube could withstand cruising speed. And even if we in this manner recovered the air lost, it seemed to me that this would be an admission of our inability to operate our ship properly.

Our real problem lay in the fact that not all the compressed air used during the day was being discharged back into the ship’s interior volume. Some of it, somehow, was escaping to the sea. Even after “pumping down” to atmospheric pressure, there was every day slightly less air in the air banks. Obviously, this had to be resolved before beginning the sealed-ship tests.

If there is no leak in an external air line, the most logical place to lose air in a submarine is in blowing sanitary tanks, and this was where, it turned out, we were losing ours. Sanitary tanks, as their name implies, are the collecting tanks for all the waste products from the ship, human and otherwise. Periodically they must be emptied, which is done with compressed air. Considerable pressure of air is required to overcome the pressure of the sea at depth, and when the blowing is finished, all this air must be vented—released—back into the ship. Despite large canisters of activated carbon filters in the vent line, the odor this air brings back with it is pungently distinguishable and fermentedly corrupt. A “good blow” scours the tank, and carries more of the noxious vapor out with the water, and investigation developed the possibility that a little too much “scouring” was costing us a lot of valuable compressed air—not to mention the betraying bubbles thereby sent to the surface.