Oil-fired steam was the only available route to a 24-knot submarine, but funnels and boiler machinery made it a poor practical solution. This differs from nuclear propulsion, which uses steam turbines without oil-fired boilers, combustion air, or retractable funnels. Seen as a two- or three-boat experiment, the K class would look like a bold attempt to push the technological envelope. A full production commitment turned a useful trial into an avoidable procurement hazard. The better next step would have been an earlier move toward River-class scale, improved or supercharged diesels, and acceptance that 22 knots might be enough.
Notable Point · 1:02:32-1:03:54
The K class was an idea ahead of its machinery
The operational concept endured, but a few experimental steam submarines would have taught the lesson without committing to a hazardous full class.