Scharnhorst vs Alaska

[parsifal]

PPS where do you get the idea that the Alaska has a consistantly heavier Broadside than the DOY?

I dont, this seems likes a simple misunderstanding. I am saying that with the Scharnhorst forced to present end on, and the alaska able to present beam on, the Alaska can fire full broadside more often than the German ship (helped along by her speede advantage). Whereas the Alaska will be able to fire 9x 12 in guns more often, and at least 6 x 12in the rest of the time, the poor old Scharnhorst can fire 9x11in fewer times, and 3x11in at other times. Thats a massive imbalance in both broadside weight and number of shells.


What the Alaska is conceding is protection.....if she gets hit, ther will be relatively more damage IMO.

I agree with your appraisal, but I would claim that there is higher probability of a first hit by the US ship. She has more guns, and I believe her radar to be superior. Germans have the advantage n optics, but thats of limited value in this battle. Its night and appalling weather

 

[Juha]

Hello Parsifal
no need to wait sundown, dawn was still some 3 weeks away on 26 Dec.

Scharnhorst still had its second radar on the rear rangefinder, so moving away from its wooded sector ie the say 30-60deg sector straight ahead of Scharnhorst would mean that if the Scharnhorst used its radar you would lose the surprise.

Juha

 

[Juha]

In other words KM command and control was incompetent. So KM Scharnhorst was doomed before the first shot was fired.

Not necessarily doomed but was put into unnecessarily risky situation. KM command structures were sometimes overly complicated and the shore HQs at times did a sloppy job, as in this time. Also the co-op between LW and KM wasn't at times very good.

Juha

 

[Glider]

Now I get it, put my lack of divvy to the end of a long day

 

[parsifal]

Hello Parsifal
no need to wait sundown, dawn was still some 3 weeks away on 26 Dec.

Scharnhorst still had its second radar on the rear rangefinder, so moving away from its wooded sector ie the say 30-60deg sector straight ahead of Scharnhorst would mean that if the Scharnhorst used its radar you would lose the surprise.

Juha

I agree, but werent the Scharnhorsts radars switched off before the engagement? And in any event, the allies dont know that the forward radar was knocked out do they, or that the rear radar was still functional. You can only develop a plan when "re-enacting" the battle on the basis of best possible practice with availbale known, or reasonably knwown information. I am assuming that the Allies would know the weakest firing arc of the German ship and other generally known characteristics like maximum speed, but wont know operational practices or states like radars on/off or radars disabled...



I am no expert in radar, but Ive read somewhere that the radar fitted to the Scharnhorst was not as accurate as that fitted to Alaska....we are talking 1940 style radar compared to 1944-5 style radar ( I have better details at home). I am doubtful that in a radar assisted gunbfight, the German ship, with the radar suite she possessed in 1940 will be as accurate as the Alaska....

 

[Vincenzo]

the trouble is we can't compare alaska with a scharnhorst w/o hypothesis, the alaska was not on operation until february '45, at that time no more german battleships were operational so we don't known what radars can get it at time. and afaik alaska was badest of KGVs in heavy sea.

 

[parsifal]

Tactical Possibilities For Scharnhorst

This is by far the more complex and challenging exercise. My opinion is that scharnhorst was lost mostly due to circumstances beyond her control, rather than any weakness of the ship, her crew, or her captain

The main reasons for Scharnhorst loss relate to the following in my opinion

1) A lack of adequate intell. Mostly this related to the lack of co-operation between the Luftwaffe and the Navy. Far greater recon resources were needed to support the sortie than were provided, and those that were were wasted because information was not passed on to the people that mattered (the guys in the ships) in sufficient time. This suggests a clumsy and slow moving communications arrangements.......there needed to be direct and close co-operation that passed tactical recon from the air recon units to the ships much faster than occurred.

Early in the war, the Germans had usually taken to sea with detachments of their SigInt service aboard, the socalled B-Dienst, or "B" service. This had proven to be a great benefit to the intell available to the men on the spot....they had specialist radio intercept services immediately available on hand to gain valuable insight into enemy dispositions and strength. I do not believe any B service detachments were provided onboard the Scharnhorst. There were b service detachments assigned to Group North, but not directly to the ship (according to Bekker at least). If I were about to emabrk on such a hazardous mission I would dfinately want a signals intell unit onboard.

2) The operational restrictions placed on German heavy ships......"do not engage if there are equal or heavier ships opposing" or words to that effect. This was actually a dangerous policy that placed ships at greater risk than ensuring their safety. hard to know how much Hitler was responsible for this insane restriction, but it had already cost one fleet commander his job (Marschall) and probably influenced another (Lutjens) to the poinmt that it affected his operational decisions and decreased the efficiency of his ship usage.

In the context of this engagement, I dont see reversing or dropping that operational restriction as being consistent with a tactical change. Its an operational change of standard operational procedure.....a strategic shift in the way the KM used its heavy ships. Once the Alaska opens fire scharnhorst has to move to disengage, and thats a major weakness for her.

3) Operational use of Radar. Germans had this belief that radars needed to be switched off except in battle, to decrease the chances of radio detection. There was no basis for the theory, and it stands in complete contrast to the way the allies applied their radar technology....switched on to maximise detection capabilitiues....

4) Over centralised command structure. The KM tended to try and control battles from its shore based commands. The armchair admirals tended to direct the afloat commanders. This was fine in a setpiece, slow moving battle, but in a highly fluid situation like NordKapp slowed German reaction times down too much.

SHIP CHARACTERISTICS

In terms of the ship itself, I consider the Scharnhorst to be a 1st rate ship with few weaknesses. Her 11in guns were somewhat of a disadvantage, but conversely their small calibre allowed a high rate of fire. German optics were perhaps the best in the world, and their guns had a reputation for beind hitting and accurate. Their armour plate was also of very high value

If there was a weakness in the Scharnhorst it was probabaly in her radar fit. Germany developed some very high quality ship borne radars towards the end of the war, but in 1943, Scharnhorsts chief radar oufits were 2 sets (fore and aft) of the FuMO26 (fore) and the older 27 type (aft). According to Campbell the FuMO27 set had a bearing accuracy of +/- 0.25to 0.3*.

The Scharnhorst in the weeks prior to North Cape was equipped with the most update firecontrol set (FuMO26) at the foretop position and a series of radar tests and blind fire gunnery exercises that were carried out in the Fjords. Unfortunately for the Germans, the new radar set at the foretop was destroyed by a direct hit from the Norfolk in the first Skirmish leaving SH 1/2 blind and only with the older FuMO 27 radar aft. Of course once this happened the British had a significant overall radar advantage through the remaining combat scenarios that day as observed by Fraser.

FuMo26 had a new antenna array that gave less reflection from wavesand better resolution of about 300m, with range usually quoted as 20-25000m with Campbell stating the accuracy as +/- 70m. Bearing accuracy was the same as the FuMO27 at 0.25*

Despite losing its best radar, the Scharnhorst consistently straddled the Duke of York at ranges from 17,000 meters to 19,500 meters. This would have been impossible without effective radar control from the remaining set. If you're straddling, you're already shooting as accurately as you can. The Duke of York scored only about 4 hits over a period of about 70 minutes at ranges from 11,000 meters to 19,500 meters and expended many more salvoes than Scharnhorst to do that. There were, however more hits after Scharnhorst speed had been lostThis doesn't indicate a comparative accuracy disparity.


Radar does make possible quicker and more consistent straddling at longer ranges. The range accuracy of even the best optical range finders is typically 1% of the range. Radar is much more accurate. The American 40cm Mk3's accuracy was 0.1% of the range give or take 40 yards. The British 50cm Type 284M's range accuracy was 120 yards, the FuMo27 was about 300 yards. FuMO26 was about 70 yards

Another advantage of radar over optics is the ability to better determine errors in the MPI of the salvo patterns. This boiled down to the ability to discriminate between the target and the shell splashes. The range resolution of the Mk3 was 400 yards, so echoes of the target and splashes could not be readily determined if they were within 400 yards of each other . The Type 284M was markedly better than the Mk3 with a range resolution of 75-150 meters (easily the most accurate radar of its type in the midwar period). It could be better determined if the MPI wasn't squarely on the target, and correction could be made, improving the chances. Late war equipment with shorter pulse durations was better yet. Post war advances would have made possible fine corrections in MPI errors easier.

The German Seetakt radar was actually well suited to firecontrol because of its unique methods of measuring and displaying range data. In practice the operator held the pip on the null mark on the CRT and the correct range was continuously displayed, updated, and transmitted directly to the central firecontrol. The operator could zoom in on and closely examine any portion of the time base for observation purposes. But it is simply untrue to say that seetakt was more powerful or had higher resolution than equivalent british radars, mostly because of the centimetric advanantage held by the allies mid-war

The SH was equipped with special night optics, separate from the regular optics, and it fired star shell to illuminate its targets early during the engagement, along with radar ranging from the aft radar set. The SH seems to have followed the standard German shooting drill. This was to fire a first salvo disregarding exact range, just to warm up the guns and check the bearing track. Cold guns were not expected to range accurately. Then to fire two quick salvoes just short andjust long to confirm the firing solution for range. The Scharnhorst's 3rd salvo reportedly was a very close near miss right off DoY's bow. As the range increased beyond the effective range of the night optics, the SH was forced to rely on its aft radar set and it ceased to fire star shell. This was when the SH shooting became uncomfortably accurate. From approx. 17km battle range to 19.5km battle range, the SH consistently straddled the DoY. This was very impressive radar directed shooting considering the conditions.

 

[Juha]

I agree, but werent the Scharnhorsts radars switched off before the engagement?

I don't know, I only know that Scharnhorst's radar was switched off before its first firefight with RN cruisers. Don said that it was switched off during its retreat to SSE but IMHO that would have been odd, because Germans knew that the cruisers shadowed it, so IMHO Germans had nothing to gain with radar silence but much to loose.

And in any event, the allies dont know that the forward radar was knocked out do they, or that the rear radar was still functional. You can only develop a plan when "re-enacting" the battle on the basis of best possible practice with availbale known, or reasonably knwown information. I am assuming that the Allies would know the weakest firing arc of the German ship and other generally known characteristics like maximum speed, but wont know operational practices or states like radars on/off or radars disabled.

Now the cruisers claimed hits on Scharnhorst, it well might have been that they had noticed the hit on foretop that knocked off Scharnhorst's main radar, after all the distance wsn't overly long and British used starshells to illuminate Scharnhorst.

I am no expert in radar, but Ive read somewhere that the radar fitted to the Scharnhorst was not as accurate as that fitted to Alaska....we are talking 1940 style radar compared to 1944-5 style radar ( I have better details at home). I am doubtful that in a radar assisted gunbfight, the German ship, with the radar suite she possessed in 1940 will be as accurate as the Alaska....

Now IIRC Scharnhorst radar suite was modernized sometime from 41 to 43 and you cannot realistically presume that in dec 43 Alaska would have had its early 45 radar suite.

Juha

 

[parsifal]

I don't know, I only know that Scharnhorst's radar was switched off before its first firefight with RN cruisers. Don said that it was switched off during its retreat to SSE but IMHO that would have been odd, because Germans knew that the cruisers shadowed it, so IMHO Germans had nothing to gain with radar silence but much to loose.

I am unsure as well as to whether their last remaining radar was on or off prior to the final (third) engagement. One would think logically it would be on, and that might well be assumed by the Alaska in her approach. if the allies had knowledge that the foreward rdf array had been knocked out earlier, then Alaskas approach would have been the same as DoYs...ie, approach from the Scharnhorst "blind spot" that is from her fore quarters. if not the stern approach still has advantages.

In either event the result will be the same, and I think the allies would have expected this response....the Scharnhorst after receiving fire from a heavy unit will turn away from that unit and attempt to shake the allied capital ship as per the standing operational p[olicy of the KM. That immediately reduces the firepower the german ship can bring to bear to the engagement.

Now the cruisers claimed hits on Scharnhorst, it well might have been that they had noticed the hit on foretop that knocked off Scharnhorst's main radar, after all the distance wsn't overly long and British used starshells to illuminate Scharnhorst.

Yes, I agree, in which case that information is likley to have been passed to the supporting heavy unit and her battle plan adjusted accordingly. wehich means that alaska would not approach from astern, she would approach from ahead, as did the DoY. But Alaska, by reason of her additional speed, has more options to favourably position herself where and when she likes in relation to Scharnhorst.

But its more complicated than it looks. I have read that the KM had a rather strange policy as to radar usage. They worked on the theory that radar emissions could give away positions of ships, and therefore attempted to minimise their usage of active radars. There is some truth to that I believe. Radars do give off detectable signatures....though I admit i dont understand the science i ahve read in some accounts could "hear" the noise generated by DoYs 284M radar emissions, but did not know who or what, or where they were coming from. The allies also were listening for radar emissions from the Scharnhorst. But I dont know if they were hearing any at the time of the third and main engagement

The following alternatives need to be considered:

1) If Scharnhorst radar was switched off, and the allies knew about it..... the stern approach is the better option.

2) If the Allies knew the forward radar was knocked out but didnt know the remaining radar was on or off.....the forequarter approach is the better option.

3) If the allies dont know the forward radar is wrecked and know the radars are on.... its better to attack from ahead.

4) If they dont know the forward radar is wrecked, but they still know the radars are off...the stern attack is the better option or off, the stern rear

Now IIRC Scharnhorst radar suite was modernized sometime from 41 to 43 and you cannot realistically presume that in dec 43 Alaska would have had its early 45 radar suite.

I agree, but it would at least have the USN Mk III radar, which is the same as that fitted to Sth Dakota and Washington the preceding November in the fight against Kirishima. It may have even had later radar fits, which I dont have access to right at this minute, but will check and get back to you

Ive given a bit of a rundown on the MkIII capabilities in my post number #127. The American radar has some advantages relative to the type 284M and some disadvantages, but overall, is proabably about the same. Type 284M was probably superior to the FuMO27, and about equal to the FuMO26, though Scharnhorst performance later in the battle kind of challenges that comfortable asumption (many straddles from range 17000 to 19500m). FuMo27 seems to have performed quite well

 

[Juha]

Hello Parsifal
I noticed your post on radars only after I had posted my earlier messages. Without checking my sources it seems to be very solid work.

Juha

 

[parsifal]

Its not all my work...some is, but Ive also used some very good stuff by our friend Del. Credit to him, to be honest.

We have only one unknown piece of info....what is the likley radar type to be fitted to the alaska if she had been completed in 1943. Im going to assume a septemeber '43 commissioning and see what was the latest radar available to the USN at that time.\\Edit:

From my copy of Campbell and John friedmans article at Nav weapons, I have determined that the most likley surface fire control radar likley to have been fitted to an early Alaska would be either the Mk 8 or the mk 13.

For comparison friedman reports the Mark 3 (the type used against the Kirishima) as having the following characteristics:

[Mk 3
War Status: Used by US Battleships, introduced in late 1941
Installed: Mounted on Main Battery Directors
Purpose: Fire Control
Power: 15-20 KW
Wavelength: 40 cm
PRF: 1,640
Transmitter Dimensions: 12 x 3 feet (3.66 x 0.91 m)
Tracking Range: 40,000 yards (37,000 m)
Range Accuracy: 40 yards (37 m)
Bearing Accuracy: 2 mils
Resolution: 400 yards (370 m) and 10 degrees
Notes: First USA set to use lobing. 16" (40.6 cm) shell splashes could be ranged at 20,000 yards (18,500 m).

Mark 8
War Status: Used by US Battleships, introduced in l1942-43
Installed: Mounted on Main Battery Directors
Purpose: Fire Control
Power: 15-20 KW, later 20-30 KW
Wavelength: 10 cm
PRF: N/A
Transmitter Dimensions: 10.2 x 3.3 feet (3.1 x 1 m)
Tracking Range: 40,000 yards (37,000 m) on Battleship sized target
Range Accuracy: 15 yards (5 m)
Bearing Accuracy: 2 mils
Resolution: 400 yards (370 m) and 10 degrees
Notes: Scanned via pulse-switching. Mark 8 mod 0 could spot 16-inch (40.6 cm) splashes out to about 20,000 yards (18,300 m) and the improved Mark 8 mod 3 could reliably spot 14-inch (35.5 cm) and 16-inch (40.6 cm) fire out to at least 35,000 yards (32,000 m).


Mk 13
War Status: Used by US Battleships and Cruisers (date of introduction not stated in Nav weapons,, but other sources say 1943-4).
Installed: Mounted on Main Battery Directors
Purpose: Fire Control
Power: 50 KW
Wavelength: 3 cm
PRF: 1,800
Transmitter Dimensions: 8 x 2 feet (2.44 x 0.61 m)
Tracking Range: 40,000 yards (37,000 m) on Battleship sized target
Range Accuracy: 15 yards (5 m)
Bearing Accuracy: 2 mils
Resolution: 400 yards (370 m) and 10 degrees
Notes: This radar could discern individual shell splashes from 16-inch (40.6 cm) projectiles out to over 42,000 yards (38,400 m).

I think it can be safely concluded that the radar fit of the Alaska in 1943 will be better than the type 284M used by the british Battleship.

 

[parsifal]

Ive thought about this problem from the SH's perspective for a couple of days, and whilst the German ship certainly has the technical capability to win this battle, the operational restrictions the Germans placed on the ship usage makes achieving a favourable outcome difficult.

The allied weakness that would be apparent to the Germans is the convoy itself. Locate the convoy and present a credible threat to it, and the British escorts are forced to stand and fight rather than just mask and shadow the SH. Force them to fight, and you can close the range. Close the range and the probability of hits increases. Since the SH had armouring that could resist the shellfire of the british Light Forces, but the british Light Forces will need a lucky hit to hurt the SH, an opportunity exists for the SH to hurt the Brits quickly, forcing them on the defensive early, and thereby facilitating the KMs escape.


I would also kieep the German squadron concentrated as a single unit, though this would require a reduction of speed from around 30 knots maximum to 26 knots maximum. Having the German DDs there means less chance of a hit on the SH.....the Britissh will be forced to deal with the Germ,an Light ships first which pose a credible threat to the British cruisers, though I concede the risk to the german destroyers is quite high.

The problem with my tactical is that the germans never really nailed exactly wher the convoyr was. So really the best strategy I can offer is rather lame.....just start to withdraw earlier than they did.

The conclusion is that SH can only really win with strategic changes to the situation, and this is not because of the capability of the ship, but because of the operational limits placed upon her.

 

[psteel]

Duke of York could not catch Scharnhorst since the Battle cruiser could make 28 knots in heavy seas while the British could only make 24 knots due to the poor sea keeping of there escort destroyers. The German escorts were no better and only managed 25 knots at times, so what kept Bey in the battle was that he could run away from each surprise. In fact he would have gotten away had it not been for a lucky shot from Duke of York at long range that found a weakness in the deck armor; cut through and severed the steam lines cutting speed back to 20 knots. Admiral Fraser admitted as much in his diary. By the time Bey had worked back up to speed, his ship was being battered and guns silenced by BB and several CA/CL fire, while a flotilla of RN DD worked their way in to torpedo range.

BTW the German doctrine on long range detection was to use passive means to avoid giving themselves away. In early trials with surface radar they noticed they could see the enemy radar at greater range than their radar could detect the enemy. So Radar silence was observed. In fact from what I understand German naval radar was designed as fire-control radars to be turned on to get quicker firing solution. This was noticed and the Denmark Straits battle in 1941, when Lutjens used the passive sonar on the Prince Eugen to detect the Hood and Prince of Wales before they maneuvered into firing range. But later when he again used the GHG sonar to elude the shadowing RN Cruisers, Lutjens assumed that they could still see him on Radar even though it was at extreme range [41,000 yards]. In fact they had lost the Bismarck altogether and would not sight her again for 30 hours.

Meanwhile the Prince Eugen made a break out into the North Atlantic , while the Bismarck made its way towards Brest right into the jaws of Force H from Gibraltar. Of course not before the Bismarck had been subjected to several air attacks that crippled her steering and propulsion system. Had it not been for the seriousness of the bow hit and flooding from the underwater hit from Prince of Wales, the Bismarck would also have escaped into the Atlantic just like in "Operation Berlin".

Here is an interesting link exploring German Radar development.

http://www.navweaps.com/Weapons/WNGER_Radar.htm

 

[parsifal]

Duke of York could not catch Scharnhorst since the Battle cruiser could make 28 knots in heavy seas while the British could only make 24 knots due to the poor sea keeping of there escort destroyers. The German escorts were no better and only managed 25 knots at times, so what kept Bey in the battle was that he could run away from each surprise.

In fact the rate at which the the range was being opened was a little over 2.5 knots, so in effective speed the Scharnhorst was ony a little over 2 knots faster than the DoY. The was partly because SH had to turn constantly to present her beam so as to fire what remained of her broadside at DoY

In fact he would have gotten away had it not been for a lucky shot from Duke of York at long range that found a weakness in the deck armor; cut through and severed the steam lines cutting speed back to 20 knots. Admiral Fraser admitted as much in his diary. By the time Bey had worked back up to speed, his ship was being battered and guns silenced by BB and several CA/CL fire, while a flotilla of RN DD worked their way in to torpedo range.

The converse of claiming the Brits achieved a lucky hit was that despite 70 minutes of consistent straddles from the initial hit, they had only achieved 4 hits on the SH. It could be said that SH was lucky not to have been hit more times than she was.

SH also was achieving consistent straddles with her broadsides as well, so it is also arguable that she was unlucky not to have achieved a hit within that 70 minutes.

BTW the German doctrine on long range detection was to use passive means to avoid giving themselves away. In early trials with surface radar they noticed they could see the enemy radar at greater range than their radar could detect the enemy. So Radar silence was observed. In fact from what I understand German naval radar was designed as fire-control radars to be turned on to get quicker firing solution.

What you have described encapsulates the weakness of the German radar policy. They could not determine, by passive detection the size of the target, its location or its estimated speed. They could only determine that "something" was out there. Meanwhile they would blunder about the ocean, in spectacular fashion, running into traps set for them. Which was the better policy of use.....to switch on your radars and risk giving out vague indicators of your own ship, whilst obtaining detailed information about your enemy, or leaving your radars off and risk blundering into a trap.

 

[psteel]

Initially the speed advantage was 4 knots as reported by O'Hara, later with heavy seas the Scharnhorst could only make 26 knots which may explain the speed discrepancy noted. O'Hara also notes she only occasionally turned to bring Bruno turret to bare, but not long after that only Caesar turret was functioning so there was no more speed loss that way. If anything the gale force wind and seas would have slowed her down.


Just as Scharnhorst was about to escape a shell passed through a 'step' in the armor deck at 20,000 yards and 30-40° to the rear. Normally such a shell would have passed through the outer and inner vertical armored bulkheads, stuck the 80mm main armored deck and ricochet away. But the 'step' presented only another vertical plate of 80mm [ first two plates were 35-40mm each]. So the shell got through. It was a lucky shot since the line to hit was exceedingly short in height even though it ran through the engineering section of the boat.

According to most sites Duke of York got 13* 14" gun hits on Scharnhorst with the expenditure of 446 shells for a hit rate of almost 3%. Scharnhorst got two hits on Duke of York radar mast and another mast hit plus massive splinter damage from near misses on a escorting Destroyer. No record exists of her shell expenditure but it didn't help that Hintze, the skipper of the boat, ordered his twin 4.1" flak crews to armored bunkers for the duration of the battle. Since the RN DD finally brought the Scharnhorst down to 10 knots with a couple of dozen torpedo launched from 2km or less, those guns could have made a huge difference in the out come of that battle. Bey doesn't come across as a competant commander as others have noted. Prior to this command appointed days before , Bey was a Destroyer flotilla leader and not exactly an outsanding one at that.

read more about the action here...

http://www.scharnhorst-class.dk/scharnhorst/history/scharnostfront.html

 

[parsifal]

Ive read somewhere that SH is estimated to have fired about 82x11in shells at DoY equating to an accuracy of 2.43%. But cannot compare SHs firing accuracy to DoYs since DoY achieved most of her hits against a target reduced to 10 knots.

I was wondering if you knew how many shells the DoY fired in that 70 min interval whilst SH was moving at high speed. My guesstimate is that in that 70 min period she might have expended 140-235 rounds with four hits achieved. Thats a comparable situation to thjose achieved SH. If my estimates are correct, DoY firing accuracy against a moving target travelling at high speed is in the order of 1.7-2.85%. That suggests DoYs and SHs firing accuracy are about the same.

Whilst the DoY was hit, its fighting efficiency was never seriously impaired. Possibly the worst was the one that disabled her radar for a few minutes.

Dont accept the claim of an impenetrable armour scheme....there is no such beast. All ships armouring schemes can reduce damage, they cannot eliminate it altogether. Even a 6" shell can hurt a battleship, such as actually happened to SH in this fight. My opinion is that even if the main belt of the SH had not been penetrated it could still suffer a great deal of catastrophic damage from each 14in shell hit.

 

[psteel]

From what I've read the intial exchange saw DoY firing 250 shells getting 8 hits for 31:1 shot to hit ratio or 3.2%.

BTW Scharnhorst also hit the Cruiser Norfolk twice putting her in dry dock for 10 months.

 

[delcyros]

During the conditions of the engagement off Norway at North Cape, even non vital, penetrating hits had a great deal of potential to induce flooding of the wingtanks above the armour deck, creating adverse effects on the stability of the overloaden ship. SCHARNHORST would have to rely on it´s compartimentation and excess metacentric stability to counter these effects. This is well possible in good weather, but at the very poor weather off Norway?

On the other hand, could ALASKA have possibly been able to fire all her main gun turrets in a force 9 gale? I don´t think so.

Additionally, a hit through the boiler hump is possible, a very shallow, 80cm tall vertical hump in the main armour deck (think about an APC penetrating the 45mm upper side belt first (+ it´s backing), then the 30mm splinter bulkhead, then the 6mm middle patform deck and finally the 80mm boiler hump). So it´s possible technically spoken but the target area is not very large (call it Luke Skywalker!) and the fuse delay is rather short with nominal 0.025sec (british fuses).
Some authors have suggested that DoY may have hit this hump off Norway but this cannot be correct as the target angle was close to 90 deg (You don´t physically hit that hump at this acute angle) that is SCHARNHORST was heading directly away from DoY and was making good her escape when the "hit" was assumed. The trajectories and geometries involved in this situation disproove a boiler hump penetration and it appears to have been either a simple mechanical breakdown or shock damage instead from a hit on the funnel base with temporary effect in boiler room one (guess... boiler room one made trouble in each and every action involving SCHARNHORST). The temporary effect is confirmed by survivors, which reported back that full power would be aviable in ten minutes (hardly what You would expect if a 14in APC penetrates into the boiler room and bursts high order). No survivor ever told that a shell was bursting inside the vitals, rather differently, they were keen to point out that they believed the citadel was breached by torpedoes but not by gunfire hits.


I have been using various versions of Facehd in the past with great enthusiasm but rejected the whole program. It suggest´s an accuracy which simply cannot be attained when we try to verify the predicts with real world trials.
That beeing said, SCHARNHORST´s penetration data are aviable via GKdos-100 penetration curves and should be preerred instead (primary source data!). Not sure what to use in case of the US 12in, though but my impression is that Facehd should give good results for US projectiles up to 30/35 deg obliquity.

SCHARNHORST was not consistently straddled over the 70 minutes chase.

 

[psteel]

Looking at O Hara the time line suggests the incident happened at 18:22 hrs,, while Garzke and Dulin report 'about 1800 hours' Both sources reprt the Duke of York ceased fire at 1824 hrs unaware the Scharnhorst speed had been cut back to 10 knots. O'Hara reports that 20 minutes after 1800hrs the Scharnhorstt ceased fire reporting the enemy was firing over radar about 18,000 m away. Both sources suggest the projectile may have penetrated the deck at this 'boiler hump' with shell fragments cuting the steam boiler lines suddenly reducing pressure and speed. While not being a expert , I can imagine that a damage control team with intimate knowledge of this high pressure steam line could effect some kind of repair in the time allotted. Both sources report that after this incident the Scharnhorst could not manage more than 22 knots , when she was able to manage 26-28knots earlier in the sea battle depending on the seas. So whatever repairs were effected they 'seem' to be in the realm of a 'band aid solution'.

Battle at the North Cape 2

In any event looking at the above web site and connecting the 1824 time line of the Scharnhorst with the 'fire stopped' location of the Duke of York [ The same time two minutes after the reported critical hit?] it looks like a LOS between the two ships describes a 30-40° 'side angle' to any salvoes. Back at 1800 hrs the Duke of York was dead astern of the Scharnhorst, but something critical happened to cut speed before the next point.


Anyway thats the info I'm working from.

 

[barney]

Tactical Possibilities For Scharnhorst
3) Operational use of Radar. Germans had this belief that radars needed to be switched off except in battle, to decrease the chances of radio detection. There was no basis for the theory, and it stands in complete contrast to the way the allies applied their radar technology....switched on to maximise detection capabilitiues....

I was looking at the naval battles around Guadalcanal. Sometimes it wasn't working but most USA combat vessels had radar. Many had the then new 10 cm radar. The trouble was, not all admirals were knowledgeable about radar. I suggest it would be like going to the Grand Generation Center and asking how many old people have I Phones. You'll probably find a sprinkling who do but you would also find people who have never used a cell phone. So, it was with admirals and radar early in WWII.

The result was that naval flotillas were taken into combat under the command of admirals who didn't want radar turned on least they give their position away, admirals who were given constant updates from radar but ignored it while waiting for a visual sighting, to admirals who fought using radar as their main or only source of data.

So, if the Navy had a policy or doctrine on how to use radar it wasn't evident during the contest for Guadalcanal.