USS Cassin Young DD-793 - Hedgehog Anti-Sub Weapon


Anti-submarine mortar-like projectile = 7.2" dia. projectile

Explosive: 30-35lbs

Weight: 65lbs total

Sink Rate: 22-23fps = 17 seconds from firing to sink to 200 ft

Firing Pattern: Circular or oval

Distance: 100-150 yard in front of ship


Disadvantage: 40 ton recoil force



Twenty-four (24) hedgehogs fired in pairs with the launch times staggered by .1 to .2 seconds. They land in the water all at the same time approximately 200 yards ahead of the ship in a 140’ x 120’ oval pattern. The bombs then sink down and explode on contact with the submarine. When one hits and explodes, it triggers the other 23 to explode at the same time.


Launcher can be trained in an arc of 20 degrees on either side of bow, The spigots also had a tilt capability to compensate for the roll-and-pitch motion of the deck.


Hedgehog attacks had a success rate of 25% versus the approximately 9% success rate for depth charge attack.