Separating boiler and turbine groups is intended to prevent one hit from disabling all of a destroyer's propulsion machinery. Surviving boilers and turbines can keep part of the plant operating after another group is damaged. Hull subdivision also slows the consequences of damage and gives the crew time to respond. A destroyer remained vulnerable to an 8-inch shell striking a critical location. A shell passing through light superstructure could continue through without meeting enough resistance to detonate.
Notable Point · 3:00-4:03
Machinery subdivision buys time for damage control
Separated boiler and turbine groups aim to preserve propulsion after a hit, while compartmentalization gives the crew time to control damage.