This was also my impression... that ASDIC was being developed in WW1 but was too late to have an impact in that war.
But in WW2 almost all destroyers had the device right from the beginning.
__________________
E8400 @ 4.00Ghz standard vCore, Gigabyte P35C DS3R @ 445 Mhz, Leadtek GTX 280, 3 x 1GB Kingston DDR2 800 @ 890Mhz, 250GB +160GB HDD, Terratec DMX 6fire 24/96, Silverstone ST60F 600W, Logitech Z-5500 THX

|