IJN Amagi VS. USS Alaska

[USS_Ward]

Ok here's a good one, at the risk of incurring the wrath of a certain omnivorous California mammal. The never completed* IJN Amagi class battle cruiser (any one of the 4 ships can be chosen for this one) vs the American white elephant (and the class designed to counter the Amagi's), the USS Alaska (or Guam if you want). As always with these theoretical battle simulations, all ships and crew are in fighting condition and for the sake of simplicity, the Amagi class has been refitted with the Type 21,22 and 13 radars (the same radars the Yamato class had access to). Nothing compared to the Alaska's but it ought to make things as fair as possible, being that the Alaska's had access to contemporary USN capital ship radar suites.

Round 1: Both ships encounter each other in the south pacific, weather and sea conditions are favorable. Both ships are at battle stations after either radar or visual contact.

Round 2: Amagi class has the support of the Tone class cruiser Takao. Alaska class has the support of the Portland class heavy cruiser(and previous VS. contender), USS Indianapolis

*Amagi class were laid down but due to the Washington Naval Treaty were never completed. Amagi and Akagi were converted to Aircraft Carriers, with Amagi being damaged badly in an earthquake, she was scrapped.

 

[HBsennah94]

Round 1: I think Amagi triumphs on account of her 10 16.1-in guns vs 9 12-in guns.
Round 2: toss up because I can't tell.

 

[marathag]

Whomever hits first, wins.
It's Eggs armed with Sledgehammers, remember.

 

[Scott Washburn]

Interesting match up. Both have about the same armor. Alaska is faster, but Amagi has much bigger guns (although each are quite capable of penetrating the other's armor). Alaska is much newer and will have construction and damage control benefitting from wartime experience. But as Marathag notes, these sorts of duels usually come down to who can score the first serious hit. Alaska might have a slight edge on that.

 

[jsb]

the Amagi class has been refitted with

Amagi is big (41,217 t (40,566 long tons) (normal)) just how thick is her deck come 1940s....?

It was 3.7" deck but Kongos deck was increase significantly from WWI to WWII so she might easily have more come WWII?

From Navweps,
12" has, http://www.navweaps.com/Weapons/WNUS_12-50_mk8.php
20,000 yards (18,288 m) 12.73" (323 mm) 3.02" (77 mm) 1,550 fps (472 mps) 17.5
25,000 yards (22,860 m) 10.52" (267 mm) 4.02" (102 mm) 1,435 fps (437 mps) 25.3
30,000 yards (27,432 m) 9.08" (231 mm) 5.11" (130 mm) 1,400 fps (427 mps) 32.8
Amagi has 9" but at 12deg so more and 3.7" deck

16" http://www.navweaps.com/index_nathan/Penetration_Japan.php (Partial-Naval Limit-effective)
20,000 18.1-17.7-16.4 deck 2.8
30,000 13.6-13.4 -12 deck 4.9
Alaska has 9" thinning to 5" and 4" deck

I think unless the better radar allows Alaska to hit without reply Amagi wins this most of the time.....?
In daylight or close/medium range night fight at an angle Amagi will win IMO.

 

[Driftless]

I thought the Alaska's were built to counter the (unbuilt) B-65 super-cruisers.

 

[jsb]

Round 2:

Is irealvant unless close at night so IJN LLs achieve a hit, in daylight the winning BC simply kills (or drives away) the CA after winning.....

 

[Spencersj345.346]

I thought the Alaska's were built to counter the (unbuilt) B-65 super-cruisers.

Ironically the B-65s were designed to counter the Alaska's which in turn were designed to counter a rumored Japanese super cruiser project

 

[SsgtC]

It's an IJN curbstomp. The Alaska class were never intended to engage a capital ship. They were built to engage heavy cruisers. Basically reverting to the original role of the battlecruiser. The ships that were meant to take on the Amagi class were the battlecruisers of the Lexington class.

 

[eltf177]

Round 1: I think Amagi triumphs on account of her 10 16.1-in guns vs 9 12-in guns.
Round 2: toss up because I can't tell.

I have to go with this, but crew quality will be an issue. I'm assuming no air for either side?

 

[CV(N)-6]

Alaska is more of a large cruiser, Amagi is a BC, Alaska has more advanced radar, probably better damage control, and poor underwater protection, while the 12" guns are far better than those from WW1, a super-heavy shell(not sure if they made any since there weren't many new 12" in the fleet) would certainly help. I'd say Alaska hits more, but all it takes is 1-2 16" hits to cripple Alaska.

 

[WaterproofPotatoes]

A lot of it depends on how much work the Amagis get before the matchup occurs as well- is she running on overhauled turbines or does she get some brand new Kampon high-pressure boilers and Gijustu-Hombu impulse turbines scaled up to battlecruiser size or a Taiho powerplant? Would she have her original guns or new 16.1"/L50 pieces developed in the late '20s with improved turret elevation? That would probably also come with the standard IJN upgrades like lengthening at the stern, improved armour, pagoda mast, maybe a new bow. If the Amagis got built, they would more than likely be the pride of the fleet and the most useful capital ships in the IJN, and likeliest to get the full treatment.

Alaska's guns are nothing to sneeze at though. The 12"/L50s on her, firing superheavy shells, are superior in every way to the USN 14"/L45 and equal or slightly better at punching through belt armour and better at punching through deck armour than the 14"/L50

 

[Ming777]

I'm just curious what Calbear will think of this.

 

[marathag]

Alaska is more of a large cruiser, Amagi is a BC, Alaska has more advanced radar, probably better damage control, and poor underwater protection, while the 12" guns are far better than those from WW1, a super-heavy shell(not sure if they made any since there weren't many new 12" in the fleet) would certainly help. I'd say Alaska hits more, but all it takes is 1-2 16" hits to cripple Alaska.

Hiei, a BC, got tore up enough by USN 5" fire and a couple 8" salvos that she had to withdraw from Ironbottom Sound, but was unable to be towed to safety.

 

[CV(N)-6]

Hiei, a BC, got tore up enough by USN 5" fire and a couple 8" salvos that she had to withdraw from Ironbottom Sound, but was unable to be towed to safety.

Did Amagi have AoN?

 

[Zheng He]

If it's daylight at long range (Battle of the Komandorski Islands) then Alaska wins because her radar controlled guns will score first. If it's night at close range (any engagement in the Solomons) then Amagi will win because she will probably score first she probably takes some licks as well unless Alaska turns into HMS Hood.

 

[SsgtC]

Alaska is more of a large cruiser, Amagi is a BC, Alaska has more advanced radar, probably better damage control, and poor underwater protection, while the 12" guns are far better than those from WW1, a super-heavy shell(not sure if they made any since there weren't many new 12" in the fleet) would certainly help. I'd say Alaska hits more, but all it takes is 1-2 16" hits to cripple Alaska.

The USN did indeed field a super heavy shell for the 12" guns. The original 12" AP shell weighed in at 870 pounds. The AP shells fired by Alaska tipped the scales at 1,140.

 

[jsb]

The USN did indeed field a super heavy shell for the 12" guns. The original 12" AP shell weighed in at 870 pounds. The AP shells fired by Alaska tipped the scales at 1,140.

v IJN APC Type 91 2,249 lbs. (1,020 kg)

 

[SsgtC]

v IJN APC Type 91 2,249 lbs. (1,020 kg)

Not much of a contest, is it?

 

[jsb]

Not much of a contest, is it?

I think it depends on Amagis rebuild, Kongo had her deck increase from a weak WWI BC 1" mixed to 4" and Amagi might get a similar improvement (maybe similar to Nagato as will presumably Tosa class if built) if she does then even the super 12" becomes quite weak, if not its a bit of luck draw but Alaska is definitely the weaker ship its just if she can hit first due to the radar and I'm not sure on average she will.