Scharnhorst vs Alaska

[renrich]

To go along with the Scharnhorst vs Hood thread but not to hijack it, a perhaps more interesting comparison would be a Scharnhorst vs Alaska fight. A lot might depend on the weather but the Scharnhorst would have an advantage in armor and the Alaska might have a knot or two in speed, an advantage in gun power and probably in fire control. What do you think?

 

[timshatz]

Man, that's a good question.

I'm guessing (I'm sure somebody will put me straight on it) that the Alaska has the advantage in terms of Fire Control (especially the radars, assuming they have the same setup as the WW2 US BBs). Maybe the Alaska will have an edge in ROF but that's questionable.

I think the Scharnhorst was designed earlier and based on a much older design. Usually, especially with warship design, later is better.

But, like I said, I'm sure somebody will put me straight on it.

 

[DonL]

That's very easy SH has no chance under normal circumstances only if the crew of Alaska makes a fatal error.

SH could only win this match under a range of 18000m because of her very bad horizontall protection and her guns that are very poor deck penetrators. On the other hand Alsaka had a good horizontal protection and good guns for deck penetration.

for a more detail explanation look at the Hood vs SH thread #15.

It's very easy under 18000m SH is completly save against Alaska and Alaska very vulnerable under 18000m because of her thin main belt of 220mm inclined. But SH has no speed advantage over Alaska to close the range so Alaska could dictate the fight.
Over 18000m Alaska is save and SH very vulnerable. So under normal circumstances Alaska is the winner.

 

[Vincenzo]

Saw the Scharnhorst armour scheme: the main belt (350mm) is penetrated from Alaska only under 16 km, but for real damage the projectile need pass almost also a 30 mm deck (that is penetrated alone over 9 km) so the window range maybe only 11/12. the lower belt (170 mm) is penetrated to all range but need pass almost a 45 mm paratie and a 30 mm deck so need i think almost over 12 km hit. the 50 mm deck is penetrated over 13 km but under there is a 95 mm deck (or a 20 mm paratie and a 80 mm deck) so need a hit over max actual hit in WWII. the 130 mm deck need hit over max actual hit in WW II. the high belt (45mm) and after this the 95 mm deck also need a long range hit aroun a 24 km. So i think the Scharnhorst has good protection versus Alaska.
If some has scheme for Alaska i'm curious to see the other side

rewriting for missinterpretation, i left the original comment THAT it's WRONG for real Scharnhorst

he main belt (350mm) is penetrated from Alaska only under 16 km, but for real damage the projectile need pass almost a 95 mm deck but this is impossible under 16 km. the lower belt (170 mm) is penetrated to all range but need pass almost a 45 mm paratie i think this is penetrated at WWII max range. the high belt (45mm) and after this the 95 mm deck also need too long range hit for WW II. the 50 mm deck is penetrated over 13 km but under there is a 95 mm deck (or a 20 mm paratie and a 80 mm deck) so this not give possibility to hit internal part.
So for 12' of Alaska the best it's hit the lower belt, in this case the range is not very important but need lucky hit. the other area show good protection vs 12'

This is on armour scheme posted to DonL not on more partucular posted on Kurfuerst

 

[vikingBerserker]

Great comparison. Alaska has firepower and speed, Scharnhorst has the armor. Interestingly enough the Alaska's were designed to counter Scharnhorst types of ships. IMO is comes down to fire control and I'd assume the Alaska's were better.

I'd have been a good fight.

 

[Kurfürst]

Saw the Scharnhorst armour scheme: the main belt (350mm) is penetrated from Alaska only under 16 km, but for real damage the projectile need pass almost also a 30 mm deck...

Huh... ? I think you mixed it up with a poster's own armoring scheme for an 'alternate Scharnhorst', with an armor layout much like the French new battleships (thick top deck, thinner turtle deck below).

The real Scharnhorst had a 350 mm main belt, with a 105mm slope and a right behind the belt which together with the 80 mm main deck formed a turtle deck - much like Bismarck, and very hard, if not impossible to penetrate into the vitals through the belt.

 

[Juha]

Hello
on Scharnhorst defence I must add that Scharnhorst had a proper torpedo defence system which Large Cruiser Alaska didn't have, so in it more weight was available for other things like armour, armament or... Even if the torpedo defence would not have any impact on duel between the two one must remember that its inclusion made Sch more balanced design from POV of protection and survival ability.

Juha

 

[DonL]

@ Kurfürst

I agree with you.
But the very weak point is the upper belt with 45mm and this is nothing!
Up from 18000-19000m a shell can penetrate the upper belt and can go directly to and through the main deck.
And then you have a 12, 14 or 15 inch shell in the vitals

 

[renrich]

The Alaska displaced full load 34253 tons and had a top speed of 33 knots. She was armored against 12 inch shell fire barely and had poor protection against torpedos. She mounted a new type of 12 inch gun which was equivalent in performance to the US prewar 14 inch gun. Her three triple turrets could maintain an average rate of fire of 2.4-3 rounds per minute and could throw an 1140 pound AP projectile 38573 yards at an elevation of 45 degrees. With a slight speed advantage and a much longer and heavier reach with guns and probably better fire control, if well handled, the odds would seem to favor Alaska over Scharnhorst.

 

[Vincenzo]

beautiful this new schemes
The 80 mm deck it's not without defence value, also take in consideration the loss of velocity for pass the 45 mm higher belt, for Alaska 12' maybe a 20 km and over hit

 

[DonL]

@ renrich

average rate of fire of 2.4-3 rounds per minute and could throw an 1140 pound AP projectile 38573 yards at an elevation of 45 degrees.

much longer and heavier reach with guns

SH had an elevation of 40 degrees but a muzzle velocity of 890mps (Alaska 762 mps) and could shoot at a range of 44,760 yards
So yes heavier but not longer theoreticly and SH can shoot 3.5 rounds per minute
Source:
German 28 cm/54.5 (11") SK C/34

Edit:

She was armored against 12 inch shell fire barely

Yes horizontal but vertical she was weak with her 220mm inclined belt. SH can penetrate 335mm straight belt at 16,514 yards and 291mm at 20,013 yards, this is enough to go through the 220mm inclined belt at tis range.

 

[Shortround6]

Assuming a much more practical max range of 25,000-30,000yds which ship had the better chance of penetrating it's oppenents deck?

Main belt is a mighty small target compared to the deck at these ranges.

 

[Vincenzo]

Assuming a much more practical max range of 25,000-30,000yds which ship had the better chance of penetrating it's oppenents deck?

Main belt is a mighty small target compared to the deck at these ranges.

maybe best assuming max 27,000 yards (max actual hit in WWII it's around 26,500)

Scharnhorst guns are not good vs decks they have too long range so they angle of fall it's too low

 

[parsifal]

The superior radar fit out of the alaska should make her more than capable of overpowering the Scharnhorst at range or in poor weather. I will get the details of the radar fits once I am home (am interstate at the moment for work). Assuming KM operational policy of avoiding contact with same or heavier class ships, the Scharnhorst can be expected not to engage her full braoadside for much of the theoretical battle, as she makes her escape, Also presenting her stern to the enemy as opposed to her broadside on, generally means the ship is more exposed to plunging fire, since, as a generalization, azimuth is more difficult to lock onto than bearing in finding a gunnery solution

 

[Vincenzo]

The Alaska go in fleet in early '45 the Scharnhorst was sinked more one year before. only comparion possible it's whai if so need think what equip (radar) can use the Scharnhorst if was in fleet in early '45

 

[davebender]

Not so sure about this if we are comparing fire control for the same time period. U.S.S. Alaska was not worked up until December 1944. If Scharnhorst survives that long it will have late war German fire control improvements.

 

[parsifal]

Not so sure about this if we are comparing fire control for the same time period. U.S.S. Alaska was not worked up until December 1944. If Scharnhorst survives that long it will have late war German fire control improvements.

The longest ranged set developed by the germans was the FuMO 34, which had had a peak power of 125 kw and a reported theoretical range of 40-50000 metres. With a pulse width of 4 milliseconds, this was still not a short wavelength set, and did not provide surface fire control radar capability.

It does not compare very well to the equivalent USN fire control radars, of which the Mk 34 was typical. The power output of this set was 1500-2000kw, the range similar at 45000 m (before the advent of AEW this was about the limit of surface radars), Pulse width, 0.5 ms, . This setwas very accurate 15 metre error at 40000 yards. It was also capable producing very reliable range data, something even the latest naval radars in Germany could not do.

A Scharnhorst fighting an Alaska in 1945 will be fighting at a severe disadvantage due to its poor radar fits. Ship borne radar was one area in technolgy where the allies achieved a massive superiority by wars end....

 

[Vincenzo]

The longest ranged set developed by the germans was the FuMO 34, which had had a peak power of 125 kw and a reported theoretical range of 40-50000 metres. With a pulse width of 4 milliseconds, this was still not a short wavelength set, and did not provide surface fire control radar capability.

It does not compare very well to the equivalent USN fire control radars, of which the Mk 34 was typical. The power output of this set was 1500-2000kw, the range similar at 45000 m (before the advent of AEW this was about the limit of surface radars), Pulse width, 0.5 ms, . This setwas very accurate 15 metre error at 40000 yards. It was also capable producing very reliable range data, something even the latest naval radars in Germany could not do.

A Scharnhorst fighting an Alaska in 1945 will be fighting at a severe disadvantage due to its poor radar fits. Ship borne radar was one area in technolgy where the allies achieved a massive superiority by wars end....

please can you explain how work the Mk 34 fire control radar?

oh i just found that Mk 34 it's of 1953 too late for our comparation, or it'a a different Mk 34?

 

[Glider]

If the weather is good then the Alaska's advantage of its better radar will be of less importance. Both vessels will have the practical problem of hitting the other ship at great distances and experience showed that there was a practical limit of around 27-30,000 yards. Beyond this then all you will do is use up the ammunition and wear the guns down. Even in this band that chances of a hit are small to remote.

With this in mind we are looking at a combat between two well matched ships. I would tend to go with the Scharnhorst as she has one asset the Alaska doesn't and that is 5.9 secondary weapons. Should the range get to about 20,000 then these will become effective and could do telling damage to the Alaska although they would not of course penetrate her armour.

 

[renrich]

Because, Alaska had a speed advantage as well as the heavier main battery it is unlikely in clear weather during the daytime that the 5.9s would come into play. The 5.9s on Graf Spee were not able to sink any of the CLs at the Plate and they had little armor compared to Alaska.