Spaceships hull armor…solid?

[Agemegos]

Battleship guns and armour demonstrated things about impactors with velocity less than about one kilometre per second. The hardness and tensile strength of materials are much less significant when you are dealing with two or three orders of magnitude more kinetic energy per unit mass, and everything behaves in collision like several times its own mass of detonating TNT.

[Fred Brackin]

Originally Posted by The Colonel

- no-one bothered to create a battleship grade HEAT round.

From memory I believe the most powerful HEAT weapon in HT is 6Dx15 (I think that's adding together multiple stages) and that would penetrate 45 inches of RHA.

I would judge that there are plenty of battleship grade HEAT rounds. If no one has bothered to devlope them for naval cannon that says something different i.e. about commoness of targets rather than capability of rounds.

[The Colonel]

Originally Posted by Fred Brackin

From memory I believe the most powerful HEAT weapon in HT is 6Dx15 (I think that's adding together multiple stages) and that would penetrate 45 inches of RHA.

I would judge that there are plenty of battleship grade HEAT rounds. If no one has bothered to devlope them for naval cannon that says something different i.e. about commoness of targets rather than capability of rounds.

No-one bothered to create a battleship grade HEAT round - I've not even heard of prototypes being made. I suspect a big part of that was due to the limit usefulness of the penetration jet on a large, multicompartment target like a battleship. There was certainly scope for HEAT rounds to have been developed whilst there were still battleships to shoot at, but to the best of my knowledge, no-one thought it worthwhile.

Mind you, on a smaller scale, I think some of the Russian SUs were armed with smaller cut down naval guns and some of them fired HEAT, so it's possible you could have contrived to fire HEAT from a naval gun if you'd really wanted to.

[Varyon]

Originally Posted by Fred Brackin

From memory I believe the most powerful HEAT weapon in HT is 6Dx15 (I think that's adding together multiple stages) and that would penetrate 45 inches of RHA.

I would judge that there are plenty of battleship grade HEAT rounds. If no one has bothered to devlope them for naval cannon that says something different i.e. about commoness of targets rather than capability of rounds.

Would HEAT really be effective against a battleship? A tank is a relatively small target, and there's not a lot of space between the armor and the engine or only crew compartment. You hit a tank in the engine (or drivetrain), you've got a mobility kill. You hit a tank in the crew compartment, you basically get an explosion within said compartment and kill or incapacitate the crew.

But a battleship's engine is, from what I understand, deep in the ship, and has quite a few open spaces between it and the outside world. Meanwhile, while the corridors of a battleship are often cramped, there's a lot more volume involved than in a tank - you hit one of those, you'll only take out those crew members unfortunate enough to be close to where your weapon hit. I think against a battleship you're probably best off hitting it with a really bit explosion, rather than hitting it with a smaller, concentrated, directed one (like HEAT). But I could be mistaken.

[Fred Brackin]

Originally Posted by The Colonel

No-one bothered to create a battleship grade HEAT round -

Perhaps "battleship grade" means something technical to you that it does not to me. I was going with "capable of penetrating battleship armor" and there are many modern HEAT muniitions with that level of power.

More likely the laack of interest (besides the "not invented here" issue) was about firing HEAT rounds from high velocity rifled guns. The spin interfered with jet formation and this was not solved until the 60s or 70s.

Also, except for Tirpritz and its' psch war campaign to drive the British admiralty "Mad!, Mad I tell you!" there were no German capital ships left by hte time of the early HEAT warheads and the RN hadn't needed more penetration to destroy Bismarck.

In the Pacific it had become obvious that gun duels involving battleships would be quite rare.

[Witchking]

Originally Posted by Fred Brackin

Perhaps "battleship grade" means something technical to you that it does not to me. I was going with "capable of penetrating battleship armor" and there are many modern HEAT muniitions with that level of power.

More likely the laack of interest (besides the "not invented here" issue) was about firing HEAT rounds from high velocity rifled guns. The spin interfered with jet formation and this was not solved until the 60s or 70s.

Also, except for Tirpritz and its' psch war campaign to drive the British admiralty "Mad!, Mad I tell you!" there were no German capital ships left by hte time of the early HEAT warheads and the RN hadn't needed more penetration to destroy Bismarck.

In the Pacific it had become obvious that gun duels involving battleships would be quite rare.

I suspect by battleship grade he was thinking 'HEAT rounds for Battleship Main Guns' so 12'+ or over 305mm.

Since HEAT rounds were coming to be in WW2 at the same time that Carriers supplanted Battleships as 'Queens of the Sea'; I suspect that no BB HEAT rounds were made because post-1945 no BB's were made.

[johndallman]

WWII battleships had two main kinds of shell for the main guns: High-Explosive, for shore bombardment and attacking unarmoured ships, and Armour-Piercing Ballistic Capped, for attacking armoured ships. It became clear during WWII that their main role was shore bombardment, and they began to carry little or no APBC. IIRC, the US battleships at Surigao Strait got a chance to take on APBC ammunition before the battle.

[Anthony]

I suspect HEAT wouldn't do much against battleships, because by ground vehicle standards they actually have pretty thin armor for their size.

[Rupert]

Originally Posted by Fred Brackin

From memory I believe the most powerful HEAT weapon in HT is 6Dx15 (I think that's adding together multiple stages) and that would penetrate 45 inches of RHA.

I would judge that there are plenty of battleship grade HEAT rounds. If no one has bothered to devlope them for naval cannon that says something different i.e. about commoness of targets rather than capability of rounds.

There are a number of large missiles with warheads that are HEAT or 'semi-HEAT', most of them anti-shipping or multi-role with anti-shipping as one of the envisaged roles. They have warheads comparable to a large naval shell of yesteryear.

The reason they weren't invented for big naval guns is simple - there was no point, because by the time they would have been fielded, those big guns were obsolete, and that was fairly clear at the time development would've started (mid-WWII). Also, there was simply no stand-out use case for them - against cruisers normal AP shells were perfectly adequate, and against smaller ships HE shells were more than adequate. Against battleships HEAT shells would've been of limited use because their after-armour effects are far too limited and fusing them so they go off on armour but not heavy plating would've been extremely challenging, and if they went off as soon as they hit hull plating they'd be worse than even (based fused) HE.

[Rupert]

Originally Posted by Anthony

I suspect HEAT wouldn't do much against battleships, because by ground vehicle standards they actually have pretty thin armor for their size.

Their guns were also quite small for their size - a WWII medium tank would have a gun of about 3" bore, and 50-70 calibres long. A WWII battleship would have main guns of 14-18" and about 45-50 calibres long (though they had many more, of course). The latter massed very roughly a thousand times to former.

So with 1000+ times the mass with guns only ~5 times the calibre and lower velocity into the bargain it's not surprising their main armour layers were relatively thin, especially as they could use their great size to hide some of their vital components behind many empty compartments to allow fragments and blast to dissipate before reaching them. Also, unlike tanks a warship's structural plating can provide protection from blast and fragmentation, because there's room for complementation, etc. (this, BTW, makes comparing ships of different times and navies hard, because the people designing them split up what counted as 'hull' or 'frame' or 'structure' vs 'protection' or 'armour' differently).