HMS Vanguard vs all others

How high would the never-experienced-battle completed-too-late-for-WW2 but supposedly very good HMS Vanguard score aganist the upstanding ship sinkers of the BB world?

 

Although Vanguard did not fully correct what I see as the main shortcoming of the KGV class, its inadequate range, she was superior in almost every other way. The belt armor had an inch saved from its max thickness. The total broadside was marginally lighter. Beyond that, it's hard to think of any KGV advantage.
I see only one factor that might hurt Vanguard in a duel with other modern battleships. Her main guns had a relatively short range when firing with normal propellants. She was the only British ships reinforced to fire super-propellants from a 30deg mount, but she would not be able to sustain an extreme-range engagment for any length of time. Given her advanced anti-radar equipment, it's unlikely she'd have to do so.

 

Wouldn't she still be outranged by most top of the line BB's?
I thought the Hood was also able to fire super charged shots at 30 degrees?
She would be more beautiful without that flat butt and bigger guns (those turrets looks so tiny on it)!



http://www.maritimequest.com/warship_di ... d_1944.htm

 

Hee! I like the disparity between her guns and her beam. It makes her look brawny.
Hood was never equipped to fire super-charges. In fact, she never got the 6crh shell either. Vanguard, in contrast, was the only ship to receive the newest Cardonald shells which almost equaled the high-obliquity performance of US shells while retaining the large burster cavity of British shells.
The normal maximum range for Vanguard's guns would be 33,550 yards. Supercharges would extend that to 37,870 yards, which is in the same neighborhood with KGV, Bismarck, NC, and SoDak. However, she would have only a limited number of super-charges.

 

I used Navweaps as a reference for the range at max elevation

super cahrged vanguard
15"/42 (879 kg) 6crh AP Shell at 30.3 degrees 36,500 yards (33,380 m)
sodak/nc
16"/45 (1,224.7 kg) AP Mark 8 at 45 degrees 36,900 yards (33,741 m) 16"/45 (861.8 kg) HC Mark at 45 degrees 1340,180 yards (36,741 m)
KGV
14"/45 (721 kg) AP at 40.7 degrees 36,500 yards (33,380 m)
Donno if KGV had supercharged shells (coastal guns had)
Bismarck
38cm/52 (800 kg) AP at 30 degrees 39,589 yards (36,520 m)

Is there a better reference on the net?

 

The lesser range you've noted for Vanguard's super-charged gunnery is not the maximum range, but the range at average-wear velocity which is about 60f/s below new-gun velocity.
The British used super-charges for old guns whose old mountings didn't provide sufficient range--15in and 6in were the most common. KGV would not need super-charges.
Navweaps is probably the best all-around source for naval weaponry info on the web.

 

From Ome Joop's picture, I think the turrets are a bit undersized in comparison to the conning tower (if that is a conning tower). I think KGV looks better. But it's how good it is that counts. So how well would it fare against, well, Tirpitz?

 

Vanguard's radar and advanced RPC would be a tremendous advantage. You have a larger, newer ship against a smaller, older ship. Who'd win?

 

Vanguard. Now what about a South Dakota?

 

What are the broadsides of the two ships?

 

Unfortunately, I have no idea.

 

South Dakotas broadside is 24300 lbs (9x2700), Vanguard's is 15504 (8x1938).

To really get a feel of how vulnerable the two ships are to each other, you need a good armor schematic (D&G), and then you need accurate velocity and obliquity records for both guns.

http://www.geocities.com/kop_mic/

And here is where it gets fun. You need to download Nathan Okuns Facehard (For face hardened armor, usually belts) and M79APCLC (for homogeneous armor.)
http://www.navweaps.com/index_nathan/index_nathan.htm

And now its gets even more fun. Open some spreadsheets, and start calculating. Take a starting point of say 20000 yards, look up the weapons data on the first link, compare to the armor its going to hit, and use facehard to determine if it will penetrate and if so in what condition. But its not that simple, usually target angles will not be 90 degrees, so you need this program. OBLICALC.EXE on the same webpage.

So at this point you would calculate the final obliquity of a hit from say HMS Vanguard on South Dakota's 12.2in Class A armor belt. Lets say the target angle is 10 degrees, the plate is angled 19 degrees. At 20000 yards the 15in shell will fall at 17.2 degrees at 1613fps. Net obliquity then is 37.51 degrees (calculated from oblicalc.) Using US class A armor in face hard, British Carbondald shells etc, we get that at 37.51 degrees obliquity the 15in shell will hole the belt, but not penetrate it intact. But wait!

The splinter belt in front of the South Dakota belt is 1.25in STS, it won't decap 15in shells when hit at low obliquity, but it will over 15 degrees.
http://www.navweaps.com/index_tech/tech-085.htm

The obliquity of the hit on the vertical splinter belt at 10 degrees at 20000 yards is 19 degrees, so the 15in shell should be decaped, so when we recalculate in facehard, we get no holing of the plate, ie the shell completely fails.

Calculating these things can be laborious and frustrating. I used to have some calculation for the KGV, which is pretty close to the Vanguard in protection, but I can't find it now. Suffice to say that both ships look very vulnerable at low target angles, but when the target angles get over 20 degrees vanguard is well protected past 20000 yards, while South Dakota is well protected past 14000 yards or so, partially due to the decaping effect I mentioned.

 

Check out this pic of Vanguard:
http://www.history.navy.mil/photos/imag ... i03737.jpg
Here's the information on Vanguard's guns:
http://www.navweaps.com/Weapons/WNBR_15-42_mk1.htm
SoDak smiles for the camera:
http://www.history.navy.mil/photos/imag ... 466247.jpg
Here's the info on SoDak's guns:
http://www.navweaps.com/Weapons/WNUS_16-45_mk6.htm
We can see that Vanguard has eight big guns firing 1938-lb shells. SoDak has nine big guns firing 2700-lb shells.
8 x 1938 = 15,504
9 x 2700 = 24,300
Statistics never tell the whole story, but when you see a ridiculous disparity like that, you can't help seeing an advantage for one ship. Vanguard's broadside is only 64% as large as SoDak's.
The Navweaps site is fantastic for weapons info.

 

Well, South Dakota never was a bad ship. Too bad she didn't get a chance of showing her full potential at Guadalcanal. She'd have blasted Kirishima down in no time if not for those electrical failures. And Vanguard never was too shabby either.

 

OK, I've calculated the relative vulnerability of the ships belts on facehard at target angles of 10 and 20 degrees. Used the following assumptions.

South Dakota. 12.2in US class A armor belt, backed by 2in of cement and .875STS. Splinter plate of 1.25in STS

Vanguard. Machinery is 12.76in British CA armor, with 2in cement and .75 Class D backing. Vertical. Magazines are 13.75in of CA armor, same backing. Contoured to the hull so its sloped, I assumed 10 degrees which looks to be about the maximum its sloped.

At 10 degrees, Vanguard can penetrate South Dakota's belt to 20000 yards, although at this range it can only hole the belt. Effective penetration occurs at 18000 yards. This assumes the 15in avoids the 1.25in splinter belt. If it hits the splinter belt and is decapped, it fails completely at 16000 yards. At 14000 yards is just at the obliquity limit of being decapped (Obliquity on the 1.25in splinter belt is 14.18 degrees, with 15 needed for decapping), if the roll of the ship makes the shell decap, at 14000 yards vanguard can only partially penetrate south Dakotas belt.

At 20 degrees, the shell will always be decapped if it hits the splinter belt, (Probably about 90% of hits). Decapped 15in shells can only penetrate South Dakota's belt to 14000 yards (Partial penetration). They fail completely at 16000 yards. At 12000 yards they penetrate but in ineffective condition. If the shells manage to not be decapped, they can penetrate to 16000 yards (effective), failing completely at 18000 yards.


At 10 degrees South Dakota can penetrate the vertical 12.76 machinery belt of Vanguard to 26000 yards, and fails completely at 28000 yards. The sloped magazine belt of 13.74in can be penetrated effectively to 20000 yards, partial penetration at 24000 yards, and fails completely at 26000 yards.

At 20 degrees South Dakota can penetrate the machinery to 26000 yards, failing completely at 28000. It can penetrated the sloped magazines to 18000 yards effectively, partial penetration to 22000 yards, and fails completely at 24000 yards.

The turrets and barbettes of South Dakota are also much better protected, glancing hits can be withstood at very close ranges, while Vanguards turrets can be taken out at almost any range.

As far as decks go, vanguards magazines are slightly better, her machinery is slightly worse the South Dakotas. The real difference is the deck smashing 2700lb shell. M79APCBC doesn't calculate US shells correctly, but Massachusetts put a shell into Jean Bart's magazines at about 25000 yards, and this was through comparable protection to vanguards magazines. So South Dakota could probably penetrate Vanguards magazines at around 25000-26000 yards, her machinery around 23000-24000, subtract up to 5000 yards for the effect of bad rolling. Vanguard would probably need about 34000 yards to get through South Dakota's decks, same reduction possible due to rolling.

 

And Vanguard is out! The winner is South Dakota! I think. And Massachusetts actually foyght Jean Bart? And since when did penetration get worse at closer ranges? The closer the better, right? Apparently that's wrong, but why?

PS You did a lot of work, Eric45.

 

Fans of Vanguard will complain that such a analysis doesnt take into account the fact that Vanguard has more armored volume then South Dakota, and they have a point, such fine details are not included in raw armor penetration numbers. But when the armor isnt keeping out enemy shells at all, its rather academic.

Battleships have both belt (vertical) and deck (horizontal) protection. At close range, a battleship gun will impact vertical armor close to normal and at high velocity, so it will penetrate more belt armor, however its unlikely to even hit deck armor, and if it does it will bounce off. As range increases, its velocity decreases and its angle of fall gets steeper, this means it penetrates less belt armor but more deck armor. For example, at point blank range the guns of the South Dakota would penetrate 30in of US class A armor, but no deck armor, since it cant really even impact since it has no angle of fall, and therefore cant bite into the armor. At 20000 yards it will penetrate 16.9in of class A belt armor, but its now plunging at 17.9 degrees so it can penetrate 3.6in of deck armor (actually, it can penetrate more then that, US (And Japanese) shells penetrate more deck armor then current formulas can account for). Finaily at 30000 yards it can penetrate 13in of vertical Class A armor, or 6.5in of horizontal deck armor. So in my analysis above, when I say (for example) South Dakota can penetrate at a 10 degree target angle the machinery of Vanguard to 26000 yards and fails at 28000 yards, it means any range CLOSER then 26000 yards the belt will likely fail against the shell. Later when talking about deck protection, when I say the vanguards decks are likely vulnerable at 23000-24000 yards, I mean that PAST 23000 yards the deck over the machinery is vulnerable to penetration from plunging fire.

This quirk in protection lead to the concept of the immunity zone, ie a ship might be "immune" from a given gun between 20000 and 30000 yards etc.

Jean Bart was half completed with one functional turret at Casablanca. USS Massachusetts saw a bit of surface action against french vichy surface forces and also traded shots with Jean Bart (Massachusetts could spot her shots against Jean Bart, indeed couldnt even see her, so her fire was pretty random.) Incidentaly, Massachusetts hit the Vichy destoyer Milan at extreme range, probably the longest range hit on a moving target in combat for the USN, and possibly as long or longer then the longest range hits ever (Usually given to Warspite, although both Scharhorst and some IJN cruisers probably share the record.)

 

It's a pity that VANGUARD took so long to build. Had she seen action, we might have a better real knowledge of her capabilities.

 

Just like if Missouri and Yamato had a major showdown at Leyte Gulf. Now that would have been awesome.

 

You've mentioned approx 4 conflicting "records" - which one (if any) do you favour and why ?