What Happened to the Japanese Submarine
Even as the special submarine crews engaged in gallows humour, others prepared the crews for going ashore. On one of the charts recovered from Sakamaki's boat, a house in Pearl City near the PAA Clipper landing, owned by Dr. Yokichi Uyehara, was marked as "Uyehara sanitarium rakuzanso ("happy mountain retreat"). Nearby, a "boat landing" and a "white man's house" are marked for the submariners' information. This was interesting information for a submariner.
Another chart supplied to the submariners is a topographical map of O'ahu, with scant nautical navigational information but plenty of information on certain land features, like "woods," "low houses," and the location of military bases. My colleague, Tom Taylor, and I had both received aircrew survival training during our careers as naval aviators and in our opinion, this map was instantly recognisable as an escape and evasion map. Why else would a submariner need to know how to get around O'ahu on foot?
On the back of one of the charts, there is an interesting handwritten notation. Under the heading, "Articles to carry when escaping," two methods for leaving the sub are detailed: first, when alongside the mother sub; second, when going ashore. If the crew was going aboard the mother sub, they were to wear their service uniform. If going ashore, then they were instructed to go naked (the assumption here is that they would strip down to their traditional undergarment, the fundoshi).
This is especially interesting in light of the fact that both Sakamaki and Inagaki stripped off their coveralls before abandoning their submarine. It also helps to explain the set of coveralls found in the sub raised from the Keehi Lagoon (spare coveralls were not carried aboard the midget subs, so someone left without their clothes). Those crewmembers were evidently following their escape directions. I asked Vice Admiral Kazuo Ueda about the reasoning behind the instruction to go ashore naked and his response was that it would make it easier for the crew to blend in with the Japanese population on the island.