Looking for an alternative to BC.

Can a purpose built CL perform scouting functions that historically were done by BC?


  • Total voters
    37
But...

I realise that I cannot have performance and missions in scouting as OTL, by just building a 36 kts, 3-5,000 ton ship without armor or heavy guns, but I can locate their scouts/screens, and then, as the situation warrants, lead them where I want them.
The problem is of course that if you are in contact with 2 cl you don't know whether the situation warrants pulling back to your fleet or leading them away from your fleet. They could be screening the bcf or the gf and you don't know.

"A crushingly decisive battle was fought between our scouting forces and those of the enemy, with honor and glory to be had on both sides, blah blah blah..." "On a side note, the main body was unable to make contact with the core of the enemy fleet, and some speculation is that the battle of the scouts may have had something to do with this sorry lack..."
Doctrine doctrine doctrine.

Actually some theorists have proposed that type of strategy. If you beat their scouts and screens in every battle their battle line can be forced to stay in port or act inadaquately screened. If acting inadequately screened they can be ripped apart by torpedo attack.

It's a theory that wasn't uncommon at the time.

Not something I would reccomends as Germany opposing Britain. There's too many cruisers in the reserve even during ww1 for them to run out of fleet screens completely.

Post Dreadnought, Germany needs every 10,000+ ton ship to be equal to or greater than HMS Dreadnought herself, at least imo, and building ships that are as big as OTL pre dreadnoughts, and probably cost more than a pre dreadnought, that cannot fight like a dreadnought, weakens Germany's already numerically outnumbered battle line by one more ship. The thread title is what is causing the confusion I think, as folks seem to be reading it as asking for alternative battlecruisers, rather than alternatives to building battlecruisers.

Remember your unarmed scout is not gonna be free. It has engines bigger than a dreadnought and despite its small size probably weakens the German battle line as resources are invested in these scouts.

I actually think if you don't want battlecruisers and a super armoured cruiser/light battlecruiser is not to your liking either your best choice might be to roll the dice and go for an early scouting air craft carrier and accept that you are staying in port during rough seas.
 
by just building a 36 kts, 3-5,000 ton ship without armor or heavy guns, but I can locate their scouts/screens, and then, as the situation warrants, lead them where I want them.
I just don't think the light supper DD works, in addition to the above.

1- damaged ships will slow down very quickly, one unlucky hit in the engine room at range will doom this ship to RN CLs.

2- this fast scout cant push back or stop the British CLs effecting a blockade or escorting convoys, the main HSF will end up being scouted from the start of the battle by RN CLs that can relatively safely be risked in almost close blockade how do you deal with them without BCs?
 
I just don't think the light supper DD works, in addition to the above.

1- damaged ships will slow down very quickly, one unlucky hit in the engine room at range will doom this ship to RN CLs.
The innards of the ship are almost all engine room. Let's just say taking a shot is a kill. When you can combine this with the fact that you can be visible at cruiser range and not be able to Id who is shooting you (lucky fog, being outline by a setting or rising sun etc) this ship will not be able to avoid all hits.
 
I just don't think the light supper DD works.

1- damaged ships will slow down very quickly, one unlucky hit in the engine room at range will doom this ship to RN CLs.
Ships that take on water, or damage to their powerplants, yes. But not all damage is going to be below the waterline, and damage above the waterline is not going to be the end of the ship I would think. Luck works both ways, and a ship that is small and very fast is not a better target than a larger, slower ship.

2- this fast scout can't push back or stop the British CLs effecting a blockade or escorting convoys.
True, but then these fast scouts are not intended nor needed for such a mission. I'm not altering the smaller classes of the OTL IGN, just the big boys, so they retain all their torpedo boats and CL's, and these can deal with British CL attempting a close blockade. Also, the fast scouts are not built for far flung commerce raiding, and so wouldn't be attacking convoys, escorted or not.

the main HSF will end up being scouted from the start of the battle by RN CLs that can relatively safely be risked in almost close blockade how do you deal with them without BCs?
Submarines, minefields, and OTL light forces, same as OTL in regards to a close blockade, and for the main body being scouted by CL's, you seem to be thinking that by building a limited number of very fast, very small specialized scouts, that all the OTL screening forces somehow get butterflied away?

The innards of the ship are almost all engine room. Let's just say taking a shot is a kill.
Lets not, and say we did. Not every hit is going into the hull, and a hit on the superstructure is not a kill.

When you can combine this with the fact that you can be visible at cruiser range and not be able to Id who is shooting you (lucky fog, being outline by a setting or rising sun etc) this ship will not be able to avoid all hits.
Again, luck works both way, and just because you may have a given ship experience bad luck, not every ship is going to.

There seems to be the thinking that, if bad luck were to be encountered, the IGN would loose these scouts, or at least some of them. While that is likely true, it is also not a problem, as unlike OTL, we are not talking about the loss of a big, expensive battleship sized vessel, but something smaller and expendable. Yes, the small scout is very much more likely to die IF they are spotted first, and IF the enemy was encountered at close range, so as to be able to open fire immediately, and IF they manage to score a crippling hit before the scout can turn away and lay down a heavy smoke screen, and...

The list goes on and on, but so what? Nobody wants to loose ships and crews, but far better to risk building many small, cheap scouts, that can cover a larger area, than building a few very big ones, that cost far too much, and cannot cover as big an area.
 
Submarines, minefields, and OTL light forces, same as OTL in regards to a close blockade, and for the main body being scouted by CL's, you seem to be thinking that by building a limited number of very fast, very small specialized scouts, that all the OTL screening forces somehow get butterflied away?
I just fail to see them achieving anything without heavy support, the RN simply deploys 6 or more "cruiser" squadrons with one I class BC supporting a screen of CLs/DDs that can simply dominate the north sea at will....

I would suggest it would be better for the HSF to not build the historic BBs than not build OTL BCs?
 
Lets not, and say we did. Not every hit is going into the hull, and a hit on the superstructure is not a kill.

With no armour if you are hit by 6 inch guns every hit by a functional shell is going into the hull. Not every shell is functioning. The defect rate at Jutland for British shells was 70% so you can take your chances.

The list goes on and on, but so what? Nobody wants to loose ships and crews, but far better to risk building many small, cheap scouts, that can cover a larger area, than building a few very big ones, that cost far too much, and cannot cover as big an area.

I've failed to get something across to you. Im sorry. We are looking at a small ship crammed full of expensive machinery. It's not a cheap ship. It's a small expensive ship.

It's small buts not cheap. We are looking at 56k horse power. That's the same as HMS Barham or her sisters. Here is a quote prepared by a British shipyard Armstrong Whitworth & co for machinery for a Queen Elizabeth class battleship at 56k ship in 1912. It's not cheap. It's 20% of the cost of a Queen Elizabeth or 45% of the cost of HMS Dreadnought.

20170815_153852.png
 
Last edited:
The problem is of course that if you are in contact with 2 cl you don't know whether the situation warrants pulling back to your fleet or leading them away from your fleet. They could be screening the bcf or the gf and you don't know.
What did the HSF want to do again, historically? Find and destroy an isolated element of the Grand Fleet. Take what comes your way. If they pursue the scouts, they don't know if they are going to run into, or away from, the HSF.

Doctrine doctrine doctrine.

Actually some theorists have proposed that type of strategy. If you beat their scouts and screens in every battle their battle line can be forced to stay in port or act inadequately screened. If acting inadequately screened they can be ripped apart by torpedo attack.

It's a theory that wasn't uncommon at the time.

Not something I would recommend, as Germany opposing Britain. There's too many cruisers in the reserve even during ww1 for them to run out of fleet screens completely.
Well, if that did come to pass, then we would end up not with an ATL where we have a much more dramatic and satisfying ATL Jutland, but an even more boring and unsatisfying ATL, without even an OTL Jutland.

Remember your unarmed scout is not gonna be free. It has engines bigger than a dreadnought and despite its small size probably weakens the German battle line as resources are invested in these scouts.
Say WHAT?!?! Not unarmed, but unarmored. A 3-5,000 ton ship requires a bigger engine? I cannot see that, could such an engine even fit? Your supposition about weakening the German battle line is missing a critical element. It isn't;
"Build the Battle Line vs Build a weaker Battle Line + these scouts", but rather
"Build the Battle Line + these scouts vs Build the Battle Line + BC's".

These scouts do not take up heavy gun production, unlike the BC's.
These scouts do not take up armor plate production, unlike the BC's.
These scouts do not take up large turret production, unlike the BC's.
These scouts do not take up large slipways needed for BB production, BC's do.
Although these ships are not free, they are cheaper than building BC's.

I actually think if you don't want battlecruisers and a super armoured cruiser/light battlecruiser is not to your liking either your best choice might be to roll the dice and go for an early scouting aircraft carrier and accept that you are staying in port during rough seas.
Well, that might work far a different ATL than the one I'm working on, lol, but not for this one.
 
Last edited:
Say WHAT?!?! Not unarmed, but unarmored. A 3-5,000 ton ship requires a bigger engine? I cannot see that, could such an engine even fit? Your supposition about weakening the German battle line is missing a critical element.
The destroyer you linked on page one has an engine that produces 170% of the power of HMS dreadnought.

We increased that by 40% to be able to support a bigger electric plant to allow non los radio and to prevent overclocking. So we have a ship with engines competitive with the Queen Elizabeth class.

I'm not sure they would fit but I assume they must ad the destroyer engine fits.

Speed is hard to get at this time.
 
Last edited:
I just fail to see them achieving anything without heavy support, the RN simply deploys 6 or more "cruiser" squadrons with one I class BC supporting a screen of CLs/DDs that can simply dominate the north sea at will....
Until you start loosing BC's to mines and submarines, and the occasional
annihilation of such a force due to the HSF catching them unawares. Faster ships don't prevent mistakes in deployment and intel, after all, so by setting out for a close blockade, you are exposing your forces to exactly the situation the Germans hoped for...

I would suggest it would be better for the HSF to not build the historic BBs than not build OTL BCs?
Well, I have to admit to not building the OTL BBs or OTL BCs in my timeline, or at least, not entirely.
 
With no armour if you are hit by 6 inch guns every hit by a functional shell is going into the hull. Not every shell is functioning. The defect rate at Jutland for British shells was 70% so you can take your chances.



I've failed to get something across to you. Im sorry. We are looking at a small ship crammed full of expensive machinery. It's not a cheap ship. It's a small expensive ship.

It's small buts not cheap. We are looking at 56k horse power. That's the same as HMS Barham or her sisters. Here is a quote prepared by a British shipyard Armstrong Whitworth & co for machinery for a Queen Elizabeth class battleship at 56k ship in 1912. It's not cheap. It's 20% of the cost of a Queen Elizabeth or 45% of the cost of HMS Dreadnought.
OUCH!!!
 
I'm sorry I'm not an engineer. I can't really explain it well that's a exponent in the formula to determine how much horsepower you need. One part of the formula is speed cubed I think but as I say I'm not a naval engineer.

So part of a formula

25x25x25=15625
35x35x35=42875

There's another part of the formula that relates weight and another to hull form but it takes almost 3 times the effort to move a ship at 35 knots as it does to move a ship at 25 knots.
 
Last edited:

Md139115

Banned
I think most posters are focusing more on the BC alternatives than BC alternative light cruisers.

If you want 30 knots and 12 inch belt in 1906 I will make a guess that you are looking at 100k horsepower and 25,000 tonnes and a cost around two to two and a half times the dreadnought. IE not small but annoying to the treasury.

That said someone may want to do it in springharp to be sure.

Sorry, I didn't have springharp to check if my idea was realistic. I also got caught up in the high numbers people were throwing around and said 30 knots in spite of the fact that even the fastest ocean liners of the day couldn't even do that (and they didn't have to worry about guns or armor ).

Let me rephrase the question this way: assuming a hull less than 500 ft long, 55 ft wide, top of the line engines, and a citadel only just big enough to keep the ship afloat if the bow and stern are shot up, what is the maximum belt armor we can fit?
 
Sorry, I didn't have springharp to check if my idea was realistic. I also got caught up in the high numbers people were throwing around and said 30 knots in spite of the fact that even the fastest ocean liners of the day couldn't even do that (and they didn't have to worry about guns or armor ).

Let me rephrase the question this way: assuming a hull less than 500 ft long, 55 ft wide, top of the line engines, and a citadel only just big enough to keep the ship afloat if the bow and stern are shot up, what is the maximum belt armor we can fit?
I don't have springsharp either. I just take various data factoids and costs and throw out estimates. I like to think I'm pretty good at it but I don't know.

30 knots and 12 inch armour is hard.

Do you have a speed target. I'm sure you can fit on 12 inch armour onto a light cruiser hull if you don't mind a sped of around 15-18 knots. Probably pointless. If you want 25 knots look at a historical ww1 light cruiser and you are kind of stuck. You can't add much more armour without making the ship bigger and adding more engines.

When you said 30 knots I found a source for the weight of armour on his Orion and HMS Renown and swapped them. Found a source for the weight of guns guns on HMS Renown and replaced them with something similar to a town classes guns and took off a little horsepower (as the weights werent too far off and renown could do 32 knots) and said that's what we are looking at.

I'm not an engineer or dnc so I can get away with back of the envelope calculations.
 
Until you start loosing BC's to mines and submarines,(1) and the occasional
annihilation of such a force due to the HSF catching them unawares.(2) Faster ships don't prevent mistakes in deployment and intel(3)
1 - If the BC is escorted by DD and doesn't go into known minefields this isn't going to work sufficiently to win.
2 - How does a slow force force battle on a far faster one? If RN BCs can reliably destroy or drive off any CL/DD force but still easily run from the HSF BBs what does the HSF do to catch them? Without BCs the Germans are at a massively disadvantage in fast scouts and losing the scouting battle means that the BB fight is on the RNs terms.....
3 - But they will allow them to reliably escape in WWI
 
Sorry, I didn't have springharp to check if my idea was realistic. I also got caught up in the high numbers people were throwing around and said 30 knots in spite of the fact that even the fastest ocean liners of the day couldn't even do that (and they didn't have to worry about guns or armor ).

Let me rephrase the question this way: assuming a hull less than 500 ft long, 55 ft wide, top of the line engines, and a citadel only just big enough to keep the ship afloat if the bow and stern are shot up, what is the maximum belt armor we can fit?

I tried to sim it but get very bad results!

ALT CL 12" belt laid down 1906

Displacement:
7,771 t light; 7,944 t standard; 8,643 t normal; 9,202 t full load
Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
(500.00 ft / 500.00 ft) x 55.00 ft x (20.00 note super deep to give more engine room its worse with less/ 21.02 ft)
(152.40 m / 152.40 m) x 16.76 m x (6.10 / 6.41 m)

Machinery:
Coal fired boilers, steam turbines,
Direct drive, 4 shafts, 66,223 shp / 49,403 Kw = 30.00 kts
Range 2,000nm at 15.00 kts
Bunker at max displacement = 1,259 tons (100% coal)

Complement:447 - 582
Cost:£0.934 million / $3.737 million

The problem is that the Armour page then says the belt says it needs 574ft to cover mags and machinery!!!!!!! (and it doesn't have any mags to cover in a 500ft ship??????)

I don't think springsharp thinks the ship can get to 30Knts, even without a belt, I think this is partly springsharp not liking fast ships but I would still doubt it can be done....
 
1 - If the BC is escorted by DD and doesn't go into known minefields this isn't going to work sufficiently to win.
2 - How does a slow force force battle on a far faster one? 2a - If RN BCs can reliably destroy or drive off any CL/DD force but still easily run from the HSF BBs what does the HSF do to catch them? 2b - Without BCs the Germans are at a massively disadvantage in fast scouts and losing the scouting battle means that the BB fight is on the RNs terms.....
3 - But they will allow them to reliably escape in WWI
Ok, i'll bite.

1) Being escorted by DD doesn't make the BC proof against submarines, nor mines, just lowers the chances, but with 6 such forces operating, sooner or later your going to loose some ships, it's just a matter of time.
2) A 5 kts speed advantage (25 kts BC vs 20 kts BB) is great, but...If the enemy is at sea, and coming back to Germany, and catches one of these 6 forces attempting a "close blockade", then you have to run less than directly away from them, or else head directly towards Germany's coast line, and then... If you withdraw your blockade every time the HSF sorties a couple BB, your blockade isn't going to be very effective. For that matter, why would the RN attempt a close blockade when a distant blockade works far better, and without risk?
2a) One word, Zeppelins. RN BC cannot outrun these, unless 25 kts is faster than 52 mph.
2b) Same as above. A close blockade isn't going to be anywhere at all like what your posts are laying out. In a perfect world, where radio intercepts always tell when the HSF is sortieing, and where never is intel failed to be passed on to the folks that need it, in time for it to be useful, then sure, it might seem like it would be easy, but the real world is going to have much to say about missed communications, and lack of perfect intel. Fog and cover of darkness allow for an unexpected close encounter, where the BC's potential speed is not going to permit them to run away in time. Also, if attempting to run away, you don't have time to conduct ASW nor look for mines that may have been deployed by submarines overnight.
3) Maybe, and maybe not. A textbook war would seem so, a real war, not so much.
 

Md139115

Banned
I don't have springsharp either. I just take various data factoids and costs and throw out estimates. I like to think I'm pretty good at it but I don't know.

30 knots and 12 inch armour is hard.

Do you have a speed target. I'm sure you can fit on 12 inch armour onto a light cruiser hull if you don't mind a sped of around 15-18 knots. Probably pointless. If you want 25 knots look at a historical ww1 light cruiser and you are kind of stuck. You can't add much more armour without making the ship bigger and adding more engines.

When you said 30 knots I found a source for the weight of armour on his Orion and HMS Renown and swapped them. Found a source for the weight of guns guns on HMS Renown and replaced them with something similar to a town classes guns and took off a little horsepower (as the weights werent too far off and renown could do 32 knots) and said that's what we are looking at.

I'm not an engineer or dnc so I can get away with back of the envelope calculations.
I tried to sim it but get very bad results!

ALT CL 12" belt laid down 1906

Displacement:
7,771 t light; 7,944 t standard; 8,643 t normal; 9,202 t full load
Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
(500.00 ft / 500.00 ft) x 55.00 ft x (20.00 note super deep to give more engine room its worse with less/ 21.02 ft)
(152.40 m / 152.40 m) x 16.76 m x (6.10 / 6.41 m)

Machinery:
Coal fired boilers, steam turbines,
Direct drive, 4 shafts, 66,223 shp / 49,403 Kw = 30.00 kts
Range 2,000nm at 15.00 kts
Bunker at max displacement = 1,259 tons (100% coal)

Complement:447 - 582
Cost:£0.934 million / $3.737 million

The problem is that the Armour page then says the belt says it needs 574ft to cover mags and machinery!!!!!!! (and it doesn't have any mags to cover in a 500ft ship??????)

I don't think springsharp thinks the ship can get to 30Knts, even without a belt, I think this is partly springsharp not liking fast ships but I would still doubt it can be done....

Yeah, just realized that I forgot to give a speed parameter... Which, given that the horsepower required does increase geometrically, is probably the most important one of all. I would love the vessel to outrun the Lion-class BCs (which did 27.5 knots) but agree that a hull too large to be cost effective would be needed. Can I get 25 to 26 knots?

At this point, I should probably be clear that I am interpreting the overall prompt to be a request for a cheaper, smaller vessel that can fulfill the scouting mission of the BC. I interpret this "scouting" to be (as a German) sailing all the way up to HMS Iron Duke, having the crew moon the ship, and making it back to Bremerhaven with the pictures to prove that, yes, smoke and fire really did shoot out of Jellicoe's mouth and ears...

Edit: And I happen to be studying mechanical engineering, so I ought to know all of this already. It's actually kind of embarrassing.
 
I would love the vessel to outrun the Lion-class BCs (which did 27.5 knots) but agree that a hull too large to be cost effective would be needed. Can I get 25 to 26 knots?
If you cant run from Lion and cant fight her off with guns you end up very dead, you cant protect everything and if she can closes you down and then hit the bow or funnels you will slow down even more until she or her LC escorts with TT sink you....

1) Being escorted by DD doesn't make the BC proof against submarines, nor mines (3), just lowers the chances, but with 6 such forces (1)operating, sooner or later your going to loose some ships, it's just a matter of time.
2) A 5 kts speed advantage (25 kts BC vs 20 kts BB) is great, but...If the enemy is at sea, and coming back to Germany,(2) and catches one of these 6 forces attempting a "close blockade", then you have to run less than directly away from them, or else head directly towards Germany's coast line, and then... If you withdraw your blockade every time the HSF sorties a couple BB, your blockade isn't going to be very effective.(4) For that matter, why would the RN attempt a close blockade when a distant blockade works far better, and without risk?
2a) One word, Zeppelins. RN BC cannot outrun these, unless 25 kts is faster than 52 mph. (3)
2b) Same as above. A close blockade isn't going to be anywhere at all like what your posts are laying out. In a perfect world, where radio intercepts always tell when the HSF is sortieing, and where never is intel failed to be passed on to the folks that need it, in time for it to be useful, then sure, it might seem like it would be easy, but the real world is going to have much to say about missed communications, and lack of perfect intel. Fog and cover of darkness allow for an unexpected close encounter, where the BC's potential speed is not going to permit them to run away in time. Also, if attempting to run away, you don't have time to conduct ASW nor look for mines that may have been deployed by submarines overnight.(3)
3) Maybe, and maybe not. A textbook war would seem so, a real war, not so much.
My problem is that without KM BCs by WWI the RN will have not 6 (1) but lots of I (6) and super I (Lx2, QM, T, R&R, LLCx3 without even adding 5QE and Hood) that can outrun the KM battleline, with sufficient scouts they are very unlikely to be caught (2) and realistically all three Subs, mines and air (3) are just not sufficiently good or reliable to kill repeatedly in the numbers needed to force the RN to lose control of the north sea scouting fight. Without wining that or even drawing as OTL the scouting battle the KM BBs are simply setting themselves up to fall into an RN BB trap eventually if they risk coming out to chase off RN BCs. The blockade (4) is going to be won almost what ever the KM/RN heavy units actually do as it can be closed mostly from almost outside the north sea, the ability of the RN to operate its scouts DDs/CLs/BCs closer to the German coast for fear of being overrun by BCs will not hurt this.
 
Historically most forward mining operations were covered by cruisers with distant cover provided by battlecruisers.

So battlecruisers was an integral part of the mining process. Without battlecruisers you risk your mining operations being disrupted by the enemy.

If Germany doesn't build counters to battlecruisers Britain are unlikely to build significantly more battlecruisers. The three invincible and maybe a single cat. All you need is a pair in service at any one time to punch through the German screen. Britain will however probably build a half dozen extra battleship with the extra funds and dockyard space.

If there's no Lion there's no reason why you need to build to escape her.
 
If Germany doesn't build counters to battlecruisers Britain are unlikely to build significantly more battlecruisers. The three invincible and maybe a single cat. All you need is a pair in service at any one time to punch through the German screen. Britain will however probably build a half dozen extra battleship with the extra funds and dockyard space.

If there's no Lion there's no reason why you need to build to escape her.
I just cant see the RN stopping building them, yes it would change from OTL but the RN would still want CL killers and it will not go back to ACRs. I think you get the original 6 Is after that I think the "Lions, QM and Tiger" just end up as super Is with all the guns on centre line 8x 12" and progressively more speed to match improvements in CLs? Unless Kongo makes Tiger go for big guns?

Without big guns to fight back it doesn't matter if the "lion" has 12" or 13.5" it will still kill you if its faster.
 
Top