A sub-1,000-ton destroyer would be too small for reliable North Sea or Pacific work, where range and seakeeping consumed more displacement. Italy could exploit shorter Mediterranean distances and generally less demanding operating conditions to build useful combatants below the counting threshold. The resulting 808-ton Spica-class boats carried three 100 mm guns, light anti-aircraft weapons, four torpedo tubes, and up to twenty mines. Calling them torpedo boats provided fleet numbers and a credible regional weapons load without entering the larger destroyer category.
Chapter · 2:29:10-2:32:42
Italy built torpedo boats beneath the destroyer threshold
The Spica class used Mediterranean operating conditions to pack useful weapons into an 808-ton standard hull that counted as a torpedo boat.