Space inside a submarine was so restricted that every choice affected another. More battery capacity could demand a longer hull, which might alter speed, handling, or structural strength. Improved camera technology in the testing facilities made it possible to evaluate U-class underwater hull performance more effectively. Those results later informed changes to S- and T-class boats, showing how experimental work on one submarine design could improve the wider force.
Chapter · 7:23-9:33
Submarine design balanced range, speed, and internal space
Submarine design choices - battery capacity, hull form, underwater speed, and range - were shaped by cramped hulls and intended theatres.