Why an air-defense Type 31 would not replace Type 83

Could an air-defense version of Type 31 do the job intended for Type 83?

The answer is no: distant ocean operations require greater missile magazine depth than the light-frigate proposal provides.

A Type 31 adapted for air defense would still face the magazine requirement behind the much larger Type 83 concept. The discussion gives rough prospective Type 83 displacement ranges of 10,000-12,000 or 12,000-15,000 tons, rather than a settled design figure. A Baltic warship can potentially dash into a nearby port to reload missiles. Ships operating in the North Atlantic, South Atlantic, or Pacific cannot assume comparably convenient resupply. Carrying enough missiles for those distant operations helps explain the proposed increase in hull size.