What is a dynamite gun

Depth charges against surface ships

One form of deep charge used during World War II was called a "hedgehog". Given the rather poor ability of the early SONAR (British "ASDIC") to locate the position of a submarine, the hedgehog projected a pattern of smaller deep charges onto the suspected location of an enemy submarine using a "mortar". The deep charges were triggered by contact fuses rather than hydrostatic fuses, with the intention that a blow to an enemy submarine from the explosion in contact with the hull would be far more devastating than the hydrostatic shock wave on which a conventional deep charge relied .

Typical hedgehog arrangement

Although the range of such a device is rather small, the idea of ​​firing large numbers of contact projectiles through the air could attack a surface ship that could cause explosive damage to the deck and superstructure of the hull above the waterline and possibly also below the waterline. More powerful projectors would allow a greater range, but also a greater spread of the pattern.

Showering a large number of similar devices from an airplane (or even an airship, don't forget that airships were used as convoy escorts during WWII, although enemy submarines were mostly spotted on or just below the surface) all in one Bombing offers a better chance of both surviving the attack and damaging the ship. Although every single bomb in a hedgehog strike is small, a large number of hits spread across the ship could incapacitate many systems and overwhelm the damage control parties, especially the attack can be pursued by several others in close order or by the same more conventional anti-ship weapons.

Another means of delivering a large deep charge like a projectile (or an actual deep charge if you can locate a submarine some distance away) would be a dynamite cannon. Using compressed air or gases, this was used to fire early high explosive grenades with a slight acceleration, as the violent acceleration of a conventional propellant could cause a grenade's HE filler to explode spontaneously in the pistol. Large versions could shoot 15 "(381 mm) projectiles from 1800-5600 m (2-5000 yards) in length, which is more useful, although it's still easily outdone by conventional artillery. The compressors and other equipment make for pretty much Large and unwieldy weapons. A smaller version, the use of a captive piston and a small explosive charge to generate compressed air "on site" was developed, but also had a correspondingly short range.

Example of the Zalinski dynamite gun

Andon

I have since longer Time seen nothing on a dynamite gun! However, I don't think they would work well as an aircraft weapon. And as much as I like the hedgehog's shotgun style, the contact detonation part isn't what I'm looking for. Also, I have my doubts about its effectiveness against surface ships, direct or not.

Thucydides

A small weapon that uses a captive piston to compress the air or an actual explosive charge in a separate chamber to provide the gas (like the Sims-Dudley dynamite cannon) is a possible aircraft weapon to carry a large, highly explosive charge with the properties of delivering a deep charge or "barrel bomb".

Andon

But why not just drop it? The first impression is that it's more complicated than it needs to be.

Thucydides

In this case, use a regular bomb. In fact, a bomb with an armor-piercing nose cap is far more useful than a deep charge for an aircraft attacking a warship. My impression is that you want a way to project a deep charge far enough from an aircraft (or ship) to safely attack a surface warship and attack submarines. Projecting a deep charge or a hedgehog provides this safety margin.