Most effective WW2 weapons against smaller warships

I saved some small amount of effort here by making a single reply to two posts. Hope this does not offend/

From Navweps Bofors 40 mm/60 (1.57") Model 1936 used a 1.960 lbs. (0.889 kg) AP M81A1 shell (so no to 5lb) that goes through 1.20" (30 mm) at 2,000 yards (1,829 m)(and at 0 yards you get 2.70" (69 mm)) but you do get 2 per second (if you can keep it feed)

Ah, so the rate of fire might be twice what I posited, while the weight of the rounds was only 40%?

So this means take my posited 100 rounds/cannon and up it to 250, and for no increase in weight? And double the rate of fire as well?


Apart from the fact that the ships are to the west of the UK and you have to fly from the east (so only a few very large Condors can really do it)
Range could/would be a problem, if we are limited to OTL Luftwaffe aircraft, but not so much for an ATL Germany that correctly identifies killing British merchantmen with long range naval aviation air fleets as THE most cost effective way to dispose of them.

and the merchant ships are not unarmed they have gun on them .5/20mm/3'/4' all later than on warships but still you are a fragile target compared to a ship and a long way from home are you really going to walk .5 fire onto a ship with its own .5s (and bigger stuff)
My understanding here is that the UK did indeed arm her merchant ships, right off the bat (in violation of international law), but the armament was IIRC 1 or more deck guns intended for engaging surfaced U-boats. I also understood that they did not supply the merchantmen with expert, naval gunners (they had non due to lack of combat up to this point), and so you end up with a few obsolete guns, operated by someone with no useful training in using them at all, let alone against aircraft/

(I'm also not sure that 30x40mm hits will sink most merchant ships (unless you hit the right parts most of yours will hit the top and grouped together from each burst)

For any weapons system, you need a reliable, well tested weapon, AND a well-trained, experienced operator, there simply is no substitute.

As posited above, a trained gunner will not fire at the ship above the waterline, but rather, form 1,000 feet above the surface, down into the water right next to the ship, thus any 40mm hits will be below the waterline, not above. For a merchantmen, 30 40mm (not even counting the explosive rounds making a much bigger hole) holes in their hull, below the waterline?

Can anyone with some physics step in here? How much water will enter a single 40mm hole in a ship’s hull per second?

I keep hearing talk here about bombs, rockets, and torpedoes, being used against small warships? The bigger the weapon used to kill them, the fewer of them you will be able to bring to bear, and thus the fewer you will sink.

Also, a pilot aiming his plane at the target has the problems listed up thread, while a dedicated turret reduces losses by not requiring the aircraft to overfly the target, and such a gunner is going to be able to concentrate his attention solely on the task at hand, not have to divide it between flying the plane and shooting accurately at the target.

You'll never achieve anything like the accuracy that a turret gunner (well trained and experienced) will achieve with unguided munitions, so more hits from the airborne 40mm, than from rockets, bombs, and torpedoes, while carrying far more ammo for such a weapon, meaning you can engage multiple targets on a single sortie, rather than one.
 
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hipper

Banned
Maybe I am mistaking but wasn't the problem more that the Germans didn't have AP shells, rather than the Stukas couldn't carry them?

the germans did have AP bombs - see the damage to HMS Nelson in 1940 off Norway - just not very many of them perhaps, and a lack of pilots trained in naval attack
 
IIRC the RAF used a special anti U boat rocket developed by the department of Misilianace weapons which had a solid steel head and was designed to travel a considerable distance and depth under water and still punch a hole through the pressure hull. A combination of those and 60lb HE war heads would IMHO be most damaging to most small/medium sized ships.
 
Range could/would be a problem, if we are limited to OTL Luftwaffe aircraft, but not so much for an ATL Germany that correctly identifies killing British merchantmen with long range naval aviation air fleets as THE most cost effective way to dispose of them.
-But any big aircraft will be expensive (range and load are not cheap)
-But the German navy isn't allowed that many aircraft (aircraft are for the
Luftwaffe)
-But the
Luftwaffe is concentration on supporting the German army ( and without that you don't get bases in France/Norway and you need much bigger aircraft)
- The British have a lot of ships (just to make it harder for you)

My understanding here is that the UK did indeed arm her merchant ships, right off the bat (in violation of international law),
Was it really Ilegal ? Myunderstanding is that it was fine the only downside is that it laid them open to Uboats without following the prize rules (but they where not going to be followed anyway) ?

but the armament was IIRC 1 or more deck guns intended for engaging surfaced U-boats. I also understood that they did not supply the merchantmen with expert, naval gunners (they had non due to lack of combat up to this point), and so you end up with a few obsolete guns, operated by someone with no useful training in using them at all, let alone against aircraft
. For any weapons system, you need a reliable, well tested weapon, AND a well-trained, experienced operator, there simply is no substitute.

As posited above, a trained gunner will not fire at the ship above the waterline, but rather, form 1,000 feet above the surface, down into the water right next to the ship, thus any 40mm hits will be below the waterline, not above. For a merchantmen, 30 40mm (not even counting the explosive rounds making a much bigger hole) holes in their hull, below the waterline?

I keep hearing talk here about bombs, rockets, and torpedoes, being used against small warships? The bigger the weapon used to kill them, the fewer of them you will be able to bring to bear, and thus the fewer you will sink.

Also, a pilot aiming his plane at the target has the problems listed up thread, while a dedicated turret reduces losses by not requiring the aircraft to overfly the target, and such a gunner is going to be able to concentrate his attention solely on the task at hand, not have to divide it between flying the plane and shooting accurately at the target.

You'll never achieve anything like the accuracy that a turret gunner (well trained and experienced) will achieve with unguided munitions, so more hits from the airborne 40mm, than from rockets, bombs, and torpedoes, while carrying far more ammo for such a weapon, meaning you can engage multiple targets on a single sortie, rather than one.
- if you get down to 1000 yards (to hit accurately) then the ships will get some hits (and aircraft can take a lot less than ships).

- Turrets make you deal with deflection shooting, nobody was good at deflection shooting unless they are very good (1% of pilots) or they had late war giro gun sights (1944+)

- OTL turrets guns don't have a good history, they are much heaver than fixed weapons and spoil the aircraft's speed and they miss a lot need more crew and cost much more .....

- Just hitting ships was hard (from a range and speed that was survivable v defensive fire) hitting just under the waterline will be very hard (and to far under the water and shells will slow down to much) I think most hits will be in well above the water line.

Personally I would go with high velocity folding fin rockets (R4M) from fighterbombers but you cant as they are 1944+
 
A Rocket salvo might scatter around the target more but an 8 Salvo rocket attack is the same HE effect as a salvo from a heavy Cruiser (the HE warhead on an RP 3 Rocket could be up to 60 pounds of Explosive) - so a near miss is going to damage a lighter ship and a hit is going to cause much more damage than a 40mm 'S' cannon Shell - which has less than a pound (454 grams) of explosive content.

Also the advantage of the rockets is that it requires few changes to the aircraft using it - unlike say mounting the Vickers S guns under the wings or a Molins gun in the hull (which prevents the Aircraft from conducting other roles).

So despite the latter guns being more accurate the Rockets were simpler and lighter.
Quite so, and they give more flexibility as the wing hardpoints could cary bombs instead. But the Beaufighter would carry the S guns internally in an existing gun bay so you would get guns and RPs or guns and bombs so the range of options is greater.
 
It seems fair to say that capital ships got increasingly vulnerable to air craft bombs and torpedoes, but fast and thinly armored targets from destroyer size and down would be increasingly harder to hit.

What would be/was the most effective air borne weapons against such targets?

Many smaller bombs
30/37/40/57/75 mm cannon fire

I honestly don't know and I've been playing around with the search strings. Let me hear some opinions or insights.

The Swordfish, as a slow biplane, was still able to roll in OG and savage a wide variety of Axis warships.
 
Quite so, and they give more flexibility as the wing hardpoints could cary bombs instead. But the Beaufighter would carry the S guns internally in an existing gun bay so you would get guns and RPs or guns and bombs so the range of options is greater.

Very true but the RP3s could be mounted on any Fighter or fighter bomber

One thing that was discovered late in the war was how good the Spitfire was as a CAS / Dive bomber - its ability pull out of a dive was superior to other types and enabled it too very accurately place its bombs (upto 2 x 250 ib and 1 x 500 ib) much more effectively and accurately than rocket attacks could.
 
-But any big aircraft will be expensive (range and load are not cheap)
-But the German navy isn't allowed that many aircraft (aircraft are for the Luftwaffe)
-But the Luftwaffe is concentration on supporting the German army ( and without that you don't get bases in France/Norway and you need much bigger aircraft)
- The British have a lot of ships (just to make it harder for you)

Was it really Ilegal ? Myunderstanding is that it was fine the only downside is that it laid them open to Uboats without following the prize rules (but they where not going to be followed anyway) ?


- if you get down to 1000 yards (to hit accurately) then the ships will get some hits (and aircraft can take a lot less than ships).

- Turrets make you deal with deflection shooting, nobody was good at deflection shooting unless they are very good (1% of pilots) or they had late war giro gun sights (1944+)

- OTL turrets guns don't have a good history, they are much heaver than fixed weapons and spoil the aircraft's speed and they miss a lot need more crew and cost much more .....

- Just hitting ships was hard (from a range and speed that was survivable v defensive fire) hitting just under the waterline will be very hard (and to far under the water and shells will slow down to much) I think most hits will be in well above the water line.

Personally I would go with high velocity folding fin rockets (R4M) from fighterbombers but you cant as they are 1944+
I'm going to take this part of the discussion to a new thread, as we seem to be getting away from topic here...
 
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