Sinking ships w/ the flak gun realistic?

[msalama]

S! all you fellow skippers.

Done this a couple of times already, i.e. have shot my last eel at a small freighter and then finished her off with the 20mm gun. Takes some ammo and time, but invariably ends in the bugger exploding spectacularly and sinking. And all this seemingly regardless of what she carries, so say an ore carrier seems to succumb just as well as an ammo freighter.

Now I'm just wondering whether you could really do this, the 20mm being a rather small-calibre weapon and everything... Well, what do you guys think, would this be possible IRL?

And mind you, this is not a gripe. Us enquiring GWX 2.0-using geezers just want to know, that's all

[Torplexed]

It wasn't uncommon for flak guns of all calibers to be pressed into use as anti-tank weapons on land in an emergency. Some like the vaunted German 88mm AA gun proved superior to most weapons designed solely for that purpose. That being said, I would think punching through the comparatively thin steel of a small freighter should be no problem for a 20mm. They won't be big holes, but they'll take their slow toll. It'd certainly keep the crew's heads down and keep them from making repairs.

As for the big ka-boom at the end...I can't say.

[Wreford-Brown]

Modern Infantry Fighting Vehicles use 20mm to 30mm ammunition and can destroy other IFVs at up to 1500m. High explosive rounds have a lethal area of 30m from the point of impact. Even allowing for the extra penetration of modern munitions, sinking a small to medium sized ship should be possible - eventually. A lot of smaller Royal Navy ships are only armed with a single 30mm cannon.

Don't forget that there's a hell of a lot of flammable material inside a ship, and ships regularly sink due to fire on board even without you pumping the hull full of holes!

[bookworm_020]

Originally Posted by Wreford-Brown

Don't forget that there's a hell of a lot of flammable material inside a ship, and ships regularly sink due to fire on board even without you pumping the hull full of holes!

Plus the damage you cause to the engines and sub systems that are needed for repair or escape.

[msalama]

Cheers guys, what you say does indeed make sense. Thanks for your answers and opinions Kaleuns

[Grayson02sept1980]

just also think about the shot cadenz... the flakguns were maybe not the biggest when it came to caliber - esspecially compare to the 105mm of the IX-boat's DG...
but the "small" 20mm let off a mass of bullet within a time... :hmm:

my brother once used his small caliber rifle (.22 Hornet) on a 10mm steelbar just to test his new bullets (hunter, making his own ammo/cardridges with special bullets for maximum efficiency on this and that game) and though it was not a full metal jacket bullet but meant to spread/collapse quickly and release the energy very quick - it went through the 10mm of steel like a hot knife through butter

Now imagine a 20mm flak gun firing with a high frequenzy :hmm:
It has to do at least "some" damage somewhere...
and now just let a bullet hit a fuel tank....

[msalama]

Now imagine a 20mm flak gun firing with a high frequenzy :hmm:
It has to do at least "some" damage somewhere...
and now just let a bullet hit a fuel tank....

Oh yeah. Seems entirely plausible to me, too, now that I think of it a bit more.

Another good example of this, BTW, is the Russian WWII PRTD / PRTS 14.5mm anti-tank rifle. The bugger wasn't particularly effective as a weapon and suffered from jamming, but still proves that a smaller-calibre weapon designed for the task should be able to do this...

Thanks guys, a veritable well of knowledge you are indeed

[siber]

Originally Posted by Grayson02sept1980

It has to do at least "some" damage somewhere...
and now just let a bullet hit a fuel tank....

Remember though that there's a big difference between a petrol (or gas for our US cousins) tank and a tank of marine diesel. You can fire a flare gun into an open tank of diesel and it won't burn.

You don't start getting diesel explosions until it's heated, vapourised and/or compressed (as inside an engine). Compared to petrol it's relatively stable because it's not at all volatile.

Aircraft burn because of their fuel. Ships burn because of their cargo... However, if there's a petrol (gasoline) cargo onboard... gametime!

[antikristuseke]

Allso petrol is not quite as volatile as most people think it is.

[Wreford-Brown]

Heat anything up to a high enough temperature and it will burn. The trick is to get something to ignite in the first place and, as bookworm_020 says, play havoc with the fire fighting systems.
Often the fire hoses were linked into steam pressure from the engines. Once the engines seized or were damaged, there was little chance of putting out anything but the smallest of fires, plus you were a sitting duck for further gunfire/torpedoes.

[Chisum]

I saw a movie of german Kriegsmarine(downloaded ont the peer to peer, enter "U-boot" in the search bar) filmed early in the war and showing a submarine attacked a ship with its deck gun.
The ship sank, but not in large explosions like in SH3.

The strongest explosions came from the explosion of shells that were ravaging on deck.
The piercing shells attacked the hull and were finally sinking the ship.

Please note that it is also possible that it was a propaganda movie...

I think personnally that the biggest explosion are correct only for the tankers and munitions ship.
I can't imagine a ship carrying coffee explode like that.
But it is a game, needs to be spectacular.

[predavolk]

I think enough damage could be done to trigger an explosion- all kinds of crazy things are possible, just not likely. Certainly, filling a ship with 200, 400, or 800 1" holes is not going to help it float, so you ought to be able to sink even a large cruise liner with enough 20mm. Armored ships would be immune if the 20mm couldn't penetrate their hulls. 800 2 cm holes is (roughly) like shooting a 20 x 80 hole in the side of the ship! That's pretty serious damage.

[ozzysoldier]

real u-boat's dit it some times on smal targets or schuteling charges and handgrenades

[piersyf]

Things to be kept in mind...

Ship hulls are NOT hardened steel unless it is the armoured belt. From memory the standard plate on a merchant is 1/4 inch mild...that's roughly equivalent to 4.5mm of hardened plate (depending on who's plate). A 20mm AP from the Oerlikon should put a hole in it quite easily at it's effective range of about 1000m. Has a chance out to around 2000. Haven't crunched the numbers on this yet...

Biggest danger is not fire, but ruptured boilers. The AP rounds will puncture a boiler. A destroyer (essentially unarmoured, with high pressure boilers and oil burners) could be very seriously hurt by 20mm fire, assuming the firer lived long enough to complete the act. Aircraft attacks on the beam were a worry. From memory even the .50cal could score mobility kills on Japanese destroyers.

Piers

[Tessa]

Originally Posted by antikristuseke

Allso petrol is not quite as volatile as most people think it is.

Quite true, its the gas that occupies the empty space between the fuel and the tank that is the dangerous part. If you hit a bomber that was almost 100% full on fuel it still could ignite and down the plane. Now take the same bomber and but it's current fuel at 25% there's a lot of fuel vapors in the tanks; hit one of them and you're gonna get a massive fireball eruption.

When you run out of eels and deck gun ammo all you've got left is the flak guns. Unless you're using one of the heavy flak cannons (3.7 mm's) shooting an untouched ship probably won't result in sinking the boat. They are good for finishing off damaged ships when you've got no other ammo left, but wouldn't really consider them for a primary way to sink ships.