The ships' shallow draft created a defensive advantage as well as giving them access to rivers and coastal waters. On one occasion, a torpedo passed beneath a monitor instead of striking it. Torpedo bulges provided another layer of protection, while an attacker needed unusually careful depth calibration to hit such a shallow target. A feature intended for river service could therefore complicate enemy torpedo attacks at sea.
Notable Point · 21:15-21:45
Shallow draft complicated torpedo attacks
The Humber class combined torpedo bulges with such shallow draft that a conventionally set torpedo could pass beneath the hull.