Felton gets this about as wrong as one possibly can.
The "Long Lance" torpedo was a 24 inch diameter torpedo launched from surface vessels such as cruisers or destroyers. Japanese submarine launched torpedoes were 21 inches in diameter. Sometimes Felton gets caught up in the "oh, breathless excitement of it all". Apparently in 1946 the event was something of a ho hum once all was said and done
Here, a USN publication, on page 9, where the torpedo in question is described as being washed ashore
PDF link
Biggest Japanese submarine success of the war was on 15 Sep 1942 with I-19 loosing a spread of torpedoes at USS Wasp, three of them hitting and sinking that ship, while the torpedoes that missed went on to the extreme of their range, one striking the destroyer USS O'Brien which eventually sank while enroute for repairs on 19 October and one other severely damaging the battleship North Carolina.
Of course, launching six torpedoes and only three of actually hit the intended target, an aircraft carrier, might give one pause to reflect on accuracy and the state of the art and technology and the monumental difficulty of attempting to strike a support tower a torpedo, especially at San Francisco, notorious for treacherous currents at the entrance to the bay . . . sitting off a major port, why waste one? Then there is the construction of the bridge with which to be concerned . . . note the really good angles of attack for this project. The whole point of the construction was to keep the towers out of the water as much as possible. And the northern tower is surrounded by rip-rap. great big rocks to stabilize the strata below. Kind of makes it hard to hit a tower surrounded by stone.
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And just what genius in the IJN figured that a torpedo hit would actually bring down the bridge? We'll never know, of course, as Felton clearly says "unrecorded". Do tell.
bases up the start of his 1:72 scale WWII Russians.
