Modern frigates and destroyers divide their sensor priorities

What distinguishes a modern frigate from a destroyer besides displacement and crew size?

Destroyers prioritize area air defence and its large radar, while frigates prioritize anti-submarine sensors and helicopter operations.

Modern type labels divide largely by mission rather than displacement or crew size. A destroyer is organised around a large air-search radar and the air-defence missile system it serves. That requirement shapes machinery, internal layout, and centre of gravity. A frigate is arranged around a towed-array sonar, other anti-submarine sensors, and helicopter support. The practical distinction is a design-priority split between air defence and submarine hunting.