Damn the Torpedoes

[Vagabond]

Recently I was lucky enough to get hold of a pair of new Martlet’s and a couple of the grey and green Beaufighter’s and was desperate to get them on the table. My thoughts turned to a solo attack on a battleship, using torpedoes and bombs from the new planes. I spent hours searching through this site for information on torpedoes in this sort of game and came up with Skafloc’s WWI and WWII Coastal Rules and Charlie3’s And all the Ships at Sea as well as a thread with some interesting observations by Flying Helmet and a partial insight into his rules but not the rules themselves.

Skafloc has lots of card damage decks in the files section but I don’t believe they all refer to the rules he has posted and I couldn’t decide which related to which set of his rules so I printed them all, intending to pick and mix what seemed best. Charlie3’s seemed to be a complete set of rules and cards so they were printed as well.
I come to this area of warfare a bit like a babe in arms, I’ve never had any interest in WWII naval games and so have no idea of the amount of damage a bomb or torpedo can do to a ship and the likely difference between different ships, eg a Merchant ship and a Bismarck.

Sorry for this preamble but I’m interested in finding a simple, cohesive set of rules to enable me to torpedo a variety of ships and do a realistic amount of damage, if anyone can point me in that direction I will be very grateful. This is what I came up with, miss matching all the information I had and as I’ve checked things to write this AAR, I see I’ve made lots of mistakes in counting the bomb damage specifically.



THE GAME

The sun was just breaking over the horizon when we made contact with the German Battleship Donutz, she was steaming south and could be seen clearly against the rising sun.


We’d had a 90 minute flight across the North Sea and had discovered her almost at the exact position the Intel chaps had given us.


The 2 Beaufighter’s were flying low, Red One was carrying a Mk13 Torpedo and Red Two had a pair of 1000lb bombs on board.


They were streaking across the sea towards the Donutz and would pretty soon get a rough reception once they came into range of the big Flak guns on the Battleship.


Blue 1 and me, Blue 2 on the port side, were flying the Martlet’s, carrying 2x100lb bombs each. The plan, which was a little loose as plans go, was for us to provide fighter cover if the Donutz was protected by German planes and keep them off the back of the Beaufighter’s and allow them to make their strikes.
Wing hadn’t been able to put together enough planes for us to make an effective attack and so we were hoping to cause enough damage to slow the Donutz down for the next wave of planes to kill her.


Red 1 drops his torpedo and runs straight into the heavy flak.

The Flak are the big AA guns from Charlie3’s rules, with a 2 ruler range, a Battleship has 4 of these, 2 either side. I used Charlie3’s burst templates placed before the plane movement card was placed and if the plane peg was in the circle it took 1D damage, In this case the peg was covered by both circles. In addition to this, once in 1 ruler range the smaller guns open fire and ALL planes take 1 or 2 B damage depending on range.

Charlie3 has torpedoes drop behind the planes and then run 5 card lengths after which they sink out of sight. He has them go end over end to cover movement with a neat 9 card deck to determine where they hit the ship, bow, amidships, and stern but I’d decided not to use his damage results and instead used Skaflok’s torpedo hit deck. This has 24 cards, 6 of which destroy the target 8 miss and the rest do different amounts of damage. I don’t think this deck of cards is what he envisioned using with his rules but I quite liked them, so removed 4 of the destroy target cards and went with the rest as is.


The big flak guns are loading but the smaller guns open fire, Red 1 is within ½ a ruler and takes 2 chits, Red 2 only takes 1.

The torpedo is now in the water and running.

Red 1’s cumulative damage is too great and he goes down in the drink.


Red 2 drops his bombs from altitude 2 and they hit amidships. Blue 1 Martlet has dropped his bombs from alt 4 and they are in flight, just beyond the splash from the Beaufighter.

The Flak guns fire again, both hitting and the smaller guns also fire, Red 2 is on borrowed time after taking 16 damage. The splash on his starboard side is all that can be seen of Red 1.


The bombs caused 100 points of damage for a direct hit and take out the A turret, using Skaflok’s Special Damage hit cards, which I believe he does mean to be used with the rules. These inflict a variety of specific damage including sometimes additional damage.
(The bombs should have caused 200 points of damage, the ship damage card I’m using is Skaflock’s Iron Duke and can take 254 points of damage, the actual paper cut out is HMS Warspite from WWI, - you take what you can get)


Blue 1’s bombs have now hit the Donutz, he is pealing away to the south, Blue 2 (me) is still flying in a straight line and has dropped his bombs and they are in flight from alt 4 and the Donutz has fired the Flak guns again.


The small 100lb bomb from Blue 1 hits and instead of causing a puny 10 points of damage the special damage card indicates that the bomb penetrated the gun magazine causing catastrophic damage and the Donutz explodes.

Well I didn’t expect that.

(Again the 10 points was for a single bomb)


This is the fire from the small AA guns on the Donutz and the torpedo is still in transit.


The explosion of the Donutz causes damage to planes within ½ and 1 ruler distance. This is sufficient to destroy Red 2 the last Beaufighter.


As the Donotz explodes in a ball of cotton wool, the torpedo and my bomb strike home. The torpedo causes 54 points of damage plus 75 from the torpedo damage deck, and I destroy the Y gun turret plus 20 points of damage.

The Donutz AA guns continue to fire to the last but probably because they have other things on their minds they miss both Martlet’s.


Blue 1 makes his turn to the south.


And I make my turn to the north.

Home in time for tea and crumpet.

I played this as a test to see if I could get something useful out of all the information I’d downloaded. When the 1st Beaufighter went down and the 2nd one flew into a wall of lead I thought it was going to be a total failure, the Martlet’s 100lb bomb blowing up the ship was a surprise, it’s very unlikely to happen, a bit like the explosion card in the regular game but it made my day and so I thought I’d share what I’d done and hope for some feedback on torpedoes and damage v ships strengths.

Originally I mistook damage per bomb in the rules for total damage and my premise that with 100 points from Red 2 plus 54 from the torpedo + 10 each from the Martlet’s together with card turn up I couldn’t destroy a 254 point battleship was correct but the reality was I had 274 points plus card turn up and so had a good chance of winning the game.

The key seems to be deciding on an appropriate level of damage a ship can take and then allocating damage from the various weapons systems but I’m open to correction. The other variable is ship movement, both rule sets use a stationary ship that can change it’s angle to incoming torpedoes and then some form of chance deck to see if the torpedoes hit.

Any thoughts?

Pip Pip
Flying Officer Vagabond

[zenlizard]

Seems like a good hybrid effort overall, but personally, I'm not convinced that a 100-lb bomb could penetrate the deck or turrettop armor on even a WW I-era battleship. YMMV.

[Stumptonian]

Great little scenario and AAR, John.
I, too, have wanted to get into anti-ship action and have downloaded a lot of files over the last 5 or 6 years but have yet to do anything with them.
Most of what I have are Skafloc's but I do have some detailed carrier operations posted by Chris Richards.
I have not seen those by Charlie3, although I ended up with a lot of duplicates from downloading into different directories, so I might have them as well.

Hoping to see comments from some of the experts.

REP AA guns are are all jammed at the moment, but this post is definitely worthy of some.
I really do like your sea mat BTW.

[Vagabond]

Seems like a good hybrid effort overall, but personally, I'm not convinced that a 100-lb bomb could penetrate the deck or turrettop armor on even a WW I-era battleship. YMMV.

YMMV ?

The special damage deck I printed is a generic one so as I understand it, any bomb has the same chance of doing the additional damage but I might be wrong there. The actual bomb damage ranges from 10 points for a 100lb bomb to 200 points on a 2000lb bomb. I didn't really look at it before playing the game apart from to have a rough idea of the average additional damage a Special Effect would have. I've just had a quick look through the deck again and there are 36 cards, about half do additional damage approx 10 points of additional damage. The rest do other things like blow up the bridge, affect fire control, radar, that sort of thing. Only 1 blows up the ship so about 3% chance which doesn't seem unreasonable but as I said I know very little about the subject.
There are 4 cards that put a turret out of action, I drew 2 of them in the game so in effect the cards I drew were completely skewed, I wonder if I didn't shuffle them well enough.

[Vagabond]

Great little scenario and AAR, John.
I, too, have wanted to get into anti-ship action and have downloaded a lot of files over the last 5 or 6 years but have yet to do anything with them.
Most of what I have are Skafloc's but I do have some detailed carrier operations posted by Chris Richards.
I have not seen those by Charlie3, although I ended up with a lot of duplicates from downloading into different directories, so I might have them as well.

Hoping to see comments from some of the experts.

REP AA guns are are all jammed at the moment, but this post is definitely worthy of some.
I really do like your sea mat BTW.

Cheers Pete, the difficulty I have is coming to this so late that people have posted rules for discussion and future amendment, as well as ones that were intended as final rules but then not everything appertaining to them was done at the same time. That's really why I'm hoping someone can point me at a finalised set.

[hokusai]

Recently I have studied skafloc's and Charlie3's work as well but have not tried them out yet. I think both systems have their charms. The good thing about house rules is that there is no right or wrong, it all depends on one's focus. So IMHO if you had fun than you did it right. I like your pictures, btw.

For my taste the torpedoes in both systems run a bit too fast. Not sure how it would feel if they ran slower, though.

As for AA fire, I still have to find a system that really convinces me. As a solo player I would like some AI AA-rules that place the blasts based on the current position/direction of the attacker, reasonably randomized so that friend or foe might or might not be hit. Something similar to the solo airplanes rules.

[Baxter]

What a great action packed AAR. The model ship looked good and I think your scenario worked very well. Probably a bit lonely with this opinion but I think a 100lb bomb could have done the job if it landed in a conflagration area caused by previous hits. There are many books about the demise of HMS Hood and most say that there were two hits in the region of the boat deck and that the second one was from the cruiser Prinz Eugen which in theory should not have penetrated the mighty Hood. I think the first hit caused fire and massive damage because of where it hit. The second just went through the damaged area like a knife through butter. Similar to the 100lb bombs I am thinking.

[Vagabond]

Recently I have studied skafloc's and Charlie3's work as well but have not tried them out yet. I think both systems have their charms. The good thing about house rules is that there is no right or wrong, it all depends on one's focus. So IMHO if you had fun than you did it right. I like your pictures, btw.

For my taste the torpedoes in both systems run a bit too fast. Not sure how it would feel if they ran slower, though.

As for AA fire, I still have to find a system that really convinces me. As a solo player I would like some AI AA-rules that place the blasts based on the current position/direction of the attacker, reasonably randomized so that friend or foe might or might not be hit. Something similar to the solo airplanes rules.

I got to Charlie3 from the link you posted the other day, thanks for that.

Regarding the speed of the torpedo, I agree it's a bit of an anomaly, as I understand it, a torpedo travels about 1 1/2 times as fast as a ship and a plane is about 10 times faster than a ship. So you could try and relate the scale movement of the plane, ship and torpedo, but then you have the issue of ground scale and model scale which are completely different, as is ship and plane model scale. Or you could ignore it and randomise the chance of a torpedo hit as they have both done.

For solo AA flak or big gun fire in WW1, I made a template on clear acitate sheet, i had a point to place around the plane, then marked 8 points on the sheet that were likely aiming points for me to try and hit the plane once it had moved, then chose the plane movement cards and then rolled a D8 to see which point the shell was fired at. I ignored altitude, I've no idea if this would work in WW2 in this game with the planes flying straight at the ship on a steady course AA was obvious.

Cheers

[Vagabond]

What a great action packed AAR. The model ship looked good and I think your scenario worked very well. Probably a bit lonely with this opinion but I think a 100lb bomb could have done the job if it landed in a conflagration area caused by previous hits. There are many books about the demise of HMS Hood and most say that there were two hits in the region of the boat deck and that the second one was from the cruiser Prinz Eugen which in theory should not have penetrated the mighty Hood. I think the first hit caused fire and massive damage because of where it hit. The second just went through the damaged area like a knife through butter. Similar to the 100lb bombs I am thinking.

Thanks Gary, on reflection with normal card draws I think the ship would have been badly damaged and all 4 planes would have been shot down, so this was an exceptional result, probably a bit like the Hood but that's way outside my sphere of knowledge.
I was really pleased with the look of the ship, 5 minutes internet search, print on card and cut out, if only all scenery was that simple.

[zenlizard]

YMMV ?

(Y)our (M)ileage (M)ay (V)ary; a disclaimer about differing opinions & experiences, a popular theft of a disclaimer used in automobile advertisements from the late 70s/80s. May in fact, may still be in use, IDK. the real point is:
The turret top/deck armor on even WW I-ear battleships is probably enough to stop a 100-lb bomb. It is only if the bomb could penetrate to the magazine before exploding that it could set off an ammunition explosion. I'm not even sure if the British had 100-lb armor piercing bombs. Armor-piercing bombs, in order to do their job and punch through a big honking sheet of armor typically have a big honking chunk of metal in the nose; this also serves to protect the fuse, as it was learned fairly early on that failure to do so often resulted in the AP bomb/shell breaking up, and the fuse never actually setting off the main charge, or the premature detonation of the bomb/shell before it had penetrated to a vital area (that is, well below or inside the armor instead of the outside.)

However, the ability of a projectile to penetrate armor depends on many factors: for example, might there be an undetected flaw in the manufacturing of either the armor or projectile which weakened either one? Has the armor been weakened by previous abuse (subjected to high stress, such as years of pitching & rolling in heavy seas, or subject to partial deformation by other projectiles that didn't penetrate-a scenario outline by Gary earlier in the thread)? What was the striking angle (if for example, the angle was 60 degrees relative to the face of the armor plate, the amount of armor the projectile has to penetrate actually doubles)?

In the final analysis, yes, YMMV. I have my personal doubts about a 100-lb aerial bombing being able to detonate the magazine of a battleship, however, in the end I am in agreement with Fabrizio: if you had fun, and the system you used worked for you, then you did it "right."

Edit to Add:
I did find this interesting, and fairly comprehensive overview of British bombs & bombing during, and between the World Wars:
https://www.rafmuseum.org.uk/documen...al_weapons.pdf

[Vagabond]

Sam - Thanks for the info and the link, what you say all makes perfect sense. I'm assuming when both these rules were written the authors wanted to introduce some variable to each hit, obviously one 1000lb bomb hit will do different damage to another 1000lb bomb hit. Maybe the variables should have been by bomb size rather than just a blanket variable for all bombs.

Do you have any bomb damage tables that you use?

[Flying Helmut]

Very nice AAR, John , and I echo the sentiments of others; that as long as you had fun, it's all to the good.


In practice, I think a 100lb bomb would be less than useless against battleship armour. Even cruiser armour would offer significant resistance.

Zenlizard's comments about armour-piercing bombs is spot on; they contain very little explosive charge when compared to other types, so have far less destructive power.


In general, in order to inflict damage on big things sturdily constructed from metal, you need to use high pressures in constricted spaces. Explosions will always seek to expand in the direction(s) of least resistance - so anything exploding on contact will release the vast majority of the destructive force into the open air, leaving very little to damage the metal structure itself.
{The Dambusters' "upkeep" bombs worked this way; rather than hit the reverse side of the dam wall, losing most of the explosive power to the open air, the bombs struck the front wall, sinking down to come to rest on the lake floor, so that when they detonated there was high resistance all around, so a much greater proportion of the force was shunted into the dam wall.}

With this in mind, nations developed several types of bombs - for simplicity, I divided them into three types

1) General Purpose (GP) bombs - these detonate on contact, so are best used against unarmoured targets like merchant ships, destroyers or airfield runways. The weight of the falling bomb is sufficient to partially penetrate the target, and the comparatively large explosive content inflicts considerable damage all around, as well as throwing debris upwards. The flash associated with the detonation starts numerous fires.

2) Armour-piercing bombs - specifically ballistically-shaped nose cap, heavy and thick, with a strong casing; comparatively little room left for the explosive charge. Needs to be dropped from high altitude, or delivered by a steep dive, in order to build so much momentum that it falls quickly and vertically to enable it to punch through a considerable thickness of steel. WW1 battleships frequently carried deck armour approaching 5 inches thick, sometimes 6 inches over vital areas like the machinery spaces and magazines. They also sported multiple thinner decks, some of these being lightly armoured decks; some had, for instance, a 2-inch main deck, a 4-inch "armour" deck, and then the magazine armour deeper in the ship.

3) Semi-Armour-Piercing (SAP) - designed to benefit from the best of both worlds: the capability to penetrate thinly armoured decks, to get deep into the bowels of the target ship before detonating in enclosed spaces to maximize damage. They necessarily had a slightly smaller explosive warhead than the GP bomb, but considerably more than the AP, to allow for there being a thicker, heavier nose cone.


I'm not aware of any nation using armour-piercing bombs as small as 100lbs - even if dropped in a steep dive, they would not have enough momentum to penetrate 5 or 6 inches of armour plate, and would have so little explosive capability as to make them almost useless.
Even 100lb GP bombs fell out of use - the U.S. Navy began WW2 by utilizing a standard load-out of 1 x 1000lb and 2 x 100lb bombs on their Dauntless dive bombers in their Bombing Squadrons (the Scouting Squadrons often used 1 x 500lb and 2 x 250lb bombs instead), but as the War progressed the 100lb bombs were no longer mounted - leaving them off improved the performance of the dive bombing plane, especially the speed and operational range.

From a table-top gaming point of view, the three types of bombs introduce interesting variables within the game; planes must attack targets for which they are carrying the appropriate bomb type, or they will inflict significantly less, or even minimal, damage.

This has a basis in historical warfare.
At the Battle of Midway, it is well known that the 'Kate' torpedo-bombers of the Kido Butai had been armed with bombs in readiness to launch a second strike against the airfields of Midway island, when the sighting report of an American carrier nearby caused them to be taken back down into the hangars to be rearmed with torpedoes.
What is less well-known is that most of the 'Val' dive-bombers were also taken down and rearmed - exchanging bombs for bombs! They were stripped of their GP airfield-busting bombs, and fitted with ship-busting SAP bombs instead.
This was all done in such a hurry that much of the removed ordnance was left strewn around the hangar decks, amongst all the tightly-packed aircraft and exposed fuel hoses, not to mention the fire curtains being left open.

When the American bombs fell, they were of the correct SAP type.

If they had been GP bombs, they might well have exploded on contact with the flight deck, blasting away the wooden planks and light steel supporting sheet, setting any exposed planes alight and hurling them over the sides, but not damaging the lower decks or impairing the carrier's seaworthiness.

Had they been AP bombs, they might well have penetrated flight deck, upper hangar deck, lower hangar "main" deck, multiple lower decks and, possibly, the hull itself, without exploding until beneath the ship, if at all.

As it was, the SAP bombs behaved exactly as designed, penetrating the flight deck, then the first hangar deck, and exploding when they impacted the armoured lower hangar deck ("main" deck). In the enclosed spaces, deep within the ship, even the small number of hits scored inflicted catastrophic damage in the hangars, starting immense conflagrations and extending destruction down below to the machinery spaces, as well as up into the upper hangar and through onto the flight deck itself.


Reports from later battles record bombs passing right through unarmoured targets such as destroyers, leaving them to limp home for repair - could these have been the wrong type of bomb to try to use on such vessels?


The problem with trying to write any set of Rules based on historical occurrences is that it is sorely tempting to accommodate every type of instance, even those which occurred only once...
Giving these any significant chance at all of happening actually skews the likelihood of all the other possible results - I have found it practicable to eliminate the extremely unlikely at both ends of the damage spectrum, leaving only the most likely consequences in place.

With this in mind, I would give a 100lb AP bomb no chance at all of damaging a battleship, or even a destroyer or cargo vessel, but with a small damage potential against a lightly-armoured target such as a Japanese or U.S carrier, or a cruiser.

[BodeGier]

Great idea and nice pictures . Well done.