Comments by "Vikki McDonough" (@vikkimcdonough6153) on "Admiral Jackie Fisher - A Most Incomparable Individual (The Man)" video.

  1. Why did the K-class submarines' steam engines make them take so long to dive? In theory, it should take well under a minute to cut off fuel to the boilers (and, with a near-stoichiometric mixture of air and oil mist or vapor actively burning, the fuel already in the boilers should burn itself out quite rapidly due to not having to burn to the center of big lumps of solid fuel), and "shut off the fuel supply" is something that has to be done when diving any submarine that burns fuel, whether that fuel be burned in a boiler for a steam engine or directly in an internal-combustion engine. On the steam side of things, since naval steam engines are almost always closed-cycle, condensing types (fresh water being somewhat harder to come by at sea), there isn't anything there that has to be released to atmosphere, and the remaining steam pressure could - conceptually - actually help in diving, as it could be used to drive the turbines and spin the propellers, thus accelerating the sub's descent when submerging below the surface using the sub's diving planes. Concerning the Ks' funnels, it seems, at least conceptually, that it should be possible to quickly slam shut a damper in the exhaust system (once the residual exhaust itself has been blown out of the system) and then submerge, with the actual folding down of the funnels not necessarily having to be required for the submarine to be watertight (meaning that it would then be possible to fold down the funnels at one's leisure, without having to wait for this to happen before submerging). What am I missing?
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