Real Submarine Technology & History Q&A

[DaveyJ576]

Originally Posted by NEON DEON

Since three of these S boats ran aground my question is:

Were the S boats equiped with depth finding equipment at the time they were lost?

My resources are pretty vague on this issue. Electronic echo-sounding fathometers came into existence as early as 1924, but the indications that I am getting is that the S-boats did not have them until they received wartime modernizations in 1943 and 44. Apparently, they did have a wire-weight sounding line that could be used from inside the boat. This is a long wire with a weight on the end that could be payed out until it struck bottom. The amount of wire payed out indicated depth. This is just a slightly more sophisticated version of the old seaman's lead line, an example of which can be seen in the recent version of King Kong, in the scene where the ship approaches the island.

The problem with this is that it could only be used when the boat is moving fairly slowly, and is only as accurate as the skill level of the man using it.

The Pacific Ocean was actually pretty poorly charted overall in the 1940's. Navigational charts for many areas were based on information gathered by Captain Cook in the 1700's. It was not uncommon to find islands that were several miles from where the chart said it was, and sounding information was scarce and inaccurate. Given this situation, it was a miracle that more boats didn't run aground.

Celestial navigation is a true art form and must be practiced constantly to maintain a safe skill set. When compared to modern GPS based systems, it is actually fairly inaccurate. Under optimum conditions, a highly experienced celestial navigator can develop a fix with an error of about a half mile in any direction. A circular error of one to three miles is normal. In the open ocean this isn't a problem and is good enough. But go into restricted waters with a half mile fix error and use a chart based on 150 year old data and you can go on the rocks pretty quick.

On her third patrol, USS Wahoo (SS-238) penetrated Wewak Harbor on the northern coast of New Guinea, despite the fact that they didn't even have a chart for it! One of the crew members produced a high school atlas and an improvised chart was drawn up. This is extraordinarily ballsy, given the navigational limitations that I outlined above. Then again, this was Mush Morton and his gang and I would not have expected anything less from them!