Hedgehog changes the anti-submarine attack

Why were Hedgehog mortars more useful than conventional depth charges in a submarine hunt?

Depth charges commonly needed multiple coordinated escorts, while a forward-thrown mortar let an escort attack without giving up its contact as completely.

Depth-charge attacks often required several escorts: one to retain ASDIC contact while others crossed the target area and laid patterns from different directions. Coordinated patterns could kill a submarine, but the method demanded several ships and careful timing. Forward-thrown anti-submarine mortars made an attack more straightforward because a ship could maintain contact while firing ahead. Hedgehog and the later Squid did not make submarine hunting easy, but they improved the tactical relationship between detection, attack, and escort coordination.