late 1943 Tirpitz instead of Bismarck in May 1941

Historical what if discussions, hypothetical operations, battleship vs. battleship engagements, design your own warship, etc.
User avatar
Dave Saxton
Supporter
Posts: 3148
Joined: Sat Nov 27, 2004 9:02 pm
Location: Rocky Mountains USA

Re: late 1943 Tirpitz instead of Bismarck in May 1941

Post by Dave Saxton »

The Fumo26 radar could easily differentiate between various types of ships; it had a range of over 30km and very good range and bearing accuracy.
Radar can not differentiate between various type of ships, or even with IFF systems, determine friends from foes with certainty. Relative ship size can only be estimated based on range of detection and pip amplitude. The accuracy and range attainment of FuMO26 was remarkable indeed.
The systems on board Bismarck (especialy the main director) were only capable of detecting enemy ships at 25km maximum, while reliable tracking and ranging in battle conditions were around 20km.
The optics were effective all the way to the optical horizon and/or to maximum visibility depending upon the conditions. Scharnhorst was tracking and ranging the Glorious by around 40km, but Marschall waited until the target was within radar range of Scharnhorst's FuMO22 (which is what it a fiited with with at the time) before giving it permission to fire at 26km.

Bismarck could have opened fire at any time inside of 36km with or without radar, but apparently Luetjens waited for target identification, and until the range was short enough to obtain more favorable danger space and hit %.
Entering a night sea battle is an awesome business.The enveloping darkness, hiding the enemy's.. seems a living thing, malignant and oppressive.Swishing water at the bow and stern mark an inexorable advance toward an unknown destiny.
dunmunro
Senior Member
Posts: 4394
Joined: Sat Oct 22, 2005 1:25 am
Location: Langley BC Canada

Re: late 1943 Tirpitz instead of Bismarck in May 1941

Post by dunmunro »

PoW engaged Bismarck, at ~18:30 on the 24th, at ~30k yds and Bismarck's return fire was extremely inaccurate, and she could not range with her stereo RFs...
Paul L
Senior Member
Posts: 317
Joined: Sat Jan 29, 2005 9:04 pm
Location: Vancouver Canada

Re: late 1943 Tirpitz instead of Bismarck in May 1941

Post by Paul L »

O'Hara puts the exchange at 1847 hours and the range of the gun duel was 26,000 yards. Lutjens was distracting RN to allow Prince Eugen to escape. pp 85

Tirpitz will escape the shadowing Cruisers the same way Bismarck did in real life by using the GHG passive sonar to detect Cruiser movement and initiate the Tirpitz turn at the same time when the Cruisers lose contact at the end of there zigzag maneuver. pp 86-87.
"Eine mal is kein mal"
dunmunro
Senior Member
Posts: 4394
Joined: Sat Oct 22, 2005 1:25 am
Location: Langley BC Canada

Re: late 1943 Tirpitz instead of Bismarck in May 1941

Post by dunmunro »

Paul L wrote:O'Hara puts the exchange at 1847 hours and the range of the gun duel was 26,000 yards. Lutjens was distracting RN to allow Prince Eugen to escape. pp 85
Well, he got the time right:
24th May. - Fire was opened at Bismarck at 1846 at a range of 30,300 yards. The table was tuned to ranges obtained from the fore D.C.T. rangefinder and "fine inclination spotting rules" were adopted, each double salvo being spread one unit apart. Salvoes 1 and 2 both fell right; salvoes 3 and 4 were fired as a further line bracket and both fell in line and short. UP 800 was ordered and salvoes 5 and 6 were fired spread one unit apart. Both these appeared in line and over; the range was then 33,000 yards and check fire was ordered. Prince of Wales then turned towards and opened fire again at 1853.5, with salvoes 7 and 8 fired as a deflection double with the table re-tuned to the fire D.C.T. rangefinder. "Y" turret was not bearing after salvo 6. Again, both these appeared right, and salvoes 9 and 10 were fired as a further line bracket. Both appeared in line and short; UP 800 was ordered and salvoes 11 and 12 were fired spread one unit apart; 11 was observed right and 12 over. Fire was then ordered to be checked by C.S.1 as the enemy turned away and there was a danger of forcing him westward.
http://www.hmshood.org.uk/reference/off ... 09guns.htm
User avatar
Dave Saxton
Supporter
Posts: 3148
Joined: Sat Nov 27, 2004 9:02 pm
Location: Rocky Mountains USA

Re: late 1943 Tirpitz instead of Bismarck in May 1941

Post by Dave Saxton »

The is how the Baron (who was there and directly involved) described this episode:
The Bismarck's gunfire, to which Schmalenbach refers, was being directed to our presistant shadower, the Suffolk. we meant her in the course of our turn, and opened fire at 18,000 meters. She immediately turned away and laid down smoke, but prince of Wales, which was farther away from us, opened up with her 356mm guns. We turned to our original planned southerly course and continued the gunnery dual with Prince of Wales. But the extreme range at which we fought, 28,000 meters, coupled with glare of the sun on the surface of the water and the clouds of stack smoke, made observation from the main fire control center in the foretop so difficult that Schneider was able to only fire single salvoes at long intervals. Since the enemy was astern of us, he eventually ordered me to take over fire control. Apparently he thought that I, in my aft station could see better. Such was not the case.
Note that the sprectral reflection was the main problem, making spotting the fall of shot too difficult. Given a different set of conditions and it may have been a different course of events for Bismarck, POW, or both. It was the conditions rather than the equipment. If Bismarck's foretop radar was available it was was at the extreme limit of its effective range to a large target. Note that 28,000 meters is fairly close to 30300 yards. So the Germans had the same range measurement. It doesn't appear that the Baron needed to mention that POWs shooting was uncomfortably close.
Entering a night sea battle is an awesome business.The enveloping darkness, hiding the enemy's.. seems a living thing, malignant and oppressive.Swishing water at the bow and stern mark an inexorable advance toward an unknown destiny.
User avatar
RF
Senior Member
Posts: 7760
Joined: Wed Sep 20, 2006 1:15 pm
Location: Wolverhampton, ENGLAND

Re: late 1943 Tirpitz instead of Bismarck in May 1941

Post by RF »

lwd wrote:I would actually expect Tirpitz to do worse. The lucky hit that destroyed Hood early in the battle is unlikly to occur in another run through of Denmark straits. As a result while POW and Hood are both likely to suffer severe damage Tirpitz is likely to take worse damage as well. PE may also be damaged in the battle.
I don't think it is that unlikely at all - I would suggest that it might happen somewhat earlier, as the fatal hit on Hood happened when the ''run in'' was practically complete. Also the German Fleet Commander might give the order to open fire fractionally earlier.
''Give me a Ping and one Ping only'' - Sean Connery.
User avatar
Karl Heidenreich
Senior Member
Posts: 4808
Joined: Thu Jan 12, 2006 3:19 pm
Location: San José, Costa Rica

Re: late 1943 Tirpitz instead of Bismarck in May 1941

Post by Karl Heidenreich »

lwd:
The lucky hit that destroyed Hood early in the battle is unlikly to occur in another run through of Denmark straits
If it was an American ship hitting another vessel then it would instantaneoulsy change from "lucky" to "proficient fire control".
An appeaser is one who feeds a crocodile, hoping it will eat him last.
Sir Winston Churchill
RobertsonN
Member
Posts: 199
Joined: Wed Jan 05, 2011 9:47 am

Re: late 1943 Tirpitz instead of Bismarck in May 1941

Post by RobertsonN »

I agree with lwd.

Offord's opinion at the second enquiry was IIRC that a shell needed to strike the 7 in belt in an area 1.5 ft high by about 40 ft long in order to strike the sloped part of the protective deck and then explode in either the after engine room or the 4 in magazines. As the main belt was 562 ft long and the total height of armor (including 5 in and 7 in) over most of that length about 24 ft, the chance of a hit in the vital area was very low. Of course some hits would also be on the forecastle deck (but these would travel over the magazines unless range was very great) and superstructure.

Is it now believed that the foretop was also hit before the fifth salvo? And was this hit likely to have been by PE?
lwd
Senior Member
Posts: 3822
Joined: Sat Jun 17, 2006 2:15 am
Location: Southfield, USA

Re: late 1943 Tirpitz instead of Bismarck in May 1941

Post by lwd »

alecsandros wrote:
lwd wrote: I don't see any difference that this would introduce. Unless of course Hood correctly IDs Tirpitz or Tirpitz opens fire on POW. Neither of which are to her benefit.
It makes a huge difference: once Hood was out (either destroyed or dead in the water), teh PoW couldn't effectively return fire.
However Hood is unlikely to be quickly silanced and your assumption of POW capability is not well supported.
Was Tirpitz really capable of maintaining a target lock?
I believe she was. Prinz Eugen ran some tests in 1943, amongst which 360* turns while mantaining a proper firing solution. If I remember correctly, Tirpitz, Gneisenau, Scheer and Hipper were scheduled for a similar refit.
Do you have some sources for this?
In any case the false torpedo alarm is another unlikely event especially as many here seem to consider it an artifact of Hood's demise.
Without the torpedo alarm to come just at the right time, PoW may also have been sunk in the historical battle against Bismarck.
Might have but highly unlikely.
Karl Heidenreich wrote:
I don't see any difference that this would introduce. Unless of course Hood correctly IDs Tirpitz or Tirpitz opens fire on POW. Neither of which are to her benefit.
That doens't change anything in reality. Hood was the first ship opening fire but by the moment she blew sky high she didn't hit anything. What would have made some people so sure she would have hit something by changes the ships it's still a matter of argument but there is no strong evidence, whatsoever, that something of the sort will happen.
It most certainly does change things. We have the word of Eugens crew that they were straddled early on and surprised that they were not hit. The implication is that there is a good chance if the Hood had opened fire on Bismarck they would have hit her. As she continues to fire the odds on a hit increase.
Now: with TIrpitz and her more sophisticated FD (and given the same circumstances) there is a highly degree of certainty that Hood would have run a similar if not equal fate and that PoW's destruction would have been more likely.
No. Certainly a superior fire control system would likely result in more hits but the likelyhood of a castrophic hit would be low and if Hood and POW have more time to return fire the German ship is also likely to be hit more often. In all likely hood lacking a catastrophic hit which is highly unlikely once Hood recieves a significant amount of damage she will withdraw and the German ships will shift fire tot he vessel that is still a threat to them if they haven't already. If the POW also takes enough damage she will likely withdraw as well and the German ships as with the historical case are unlikely to follow her. Of course the German battlships may herself recieve critcal damage before either of these points is reached.
Karl Heidenreich wrote:
The lucky hit that destroyed Hood early in the battle is unlikly to occur in another run through of Denmark straits
If it was an American ship hitting another vessel then it would instantaneoulsy change from "lucky" to "proficient fire control".
Niether accurate nor called for. Proficient fire control is determined by straddles. The number and severity of hits is a matter of luck and/or statistics. Where has someone in this or related threads suggested otherwise? Certainly I haven't.
Paul L
Senior Member
Posts: 317
Joined: Sat Jan 29, 2005 9:04 pm
Location: Vancouver Canada

Re: late 1943 Tirpitz instead of Bismarck in May 1941

Post by Paul L »

The 'lucky hit' on HMS Hood was not THAT lucky, in fact it was inevitable given such a large 'weakened area'. The significant wave height exposed this area regularly so that it was only a matter of time before one enemy shell found the way through. This was not the first time the HMS Hood was in battle.
"Eine mal is kein mal"
lwd
Senior Member
Posts: 3822
Joined: Sat Jun 17, 2006 2:15 am
Location: Southfield, USA

Re: late 1943 Tirpitz instead of Bismarck in May 1941

Post by lwd »

an area 1.5'x40' isn't small? What's the projected area of Hood at that angle? Certainly greater than 20,000 sq feet. If it's 20,000 sq feet then the odds of a hit on the aforementioned critical area is about .3% per hit. That's still less than a 3% chance after 10 hits and about a 26% chance after 100 hits. I suspect however that the projected area of the Hood was 30,000 + feet. Which would lower the odds even more.
Paul L
Senior Member
Posts: 317
Joined: Sat Jan 29, 2005 9:04 pm
Location: Vancouver Canada

Re: late 1943 Tirpitz instead of Bismarck in May 1941

Post by Paul L »

http://www.navweaps.com/index_inro/INRO_Hood_p1.htm

http://www.navweaps.com/index_inro/INRO_Hood_p2.htm

http://www.navweaps.com/index_inro/INRO_Hood_p3.htm

http://www.navweaps.com/index_inro/INRO_Hood_p4.htm

Looking at the target based on the 10% hit chance , it reminds me of the same chance of the POW striking Scharnhorst 'step' in the deck leading to warship stalling allowing the RN to catch up and destroy the battleship.

Given enough hits over number of incidents, it was bound to happen sooner or later to either of these battleships, HMS Hood or the Scharnhorst.
"Eine mal is kein mal"
User avatar
Karl Heidenreich
Senior Member
Posts: 4808
Joined: Thu Jan 12, 2006 3:19 pm
Location: San José, Costa Rica

Re: late 1943 Tirpitz instead of Bismarck in May 1941

Post by Karl Heidenreich »

Paul L
The 'lucky hit' on HMS Hood was not THAT lucky, in fact it was inevitable given such a large 'weakened area'. The significant wave height exposed this area regularly so that it was only a matter of time before one enemy shell found the way through. This was not the first time the HMS Hood was in battle.
Correct.

Let's see which part of it was "lucky":

1. The weak horizontal armor of Hood, which was penetrated by the 15" shell. Even the British knew how weak it was and was determinant in how Holland tried to close the range between them and Bismarck in the moment of the combat itself. No luck there, it was a technical issue from Hood's design and construction.

2. The way Hollant approached Bismarck that dawn after Norfolk and Suffolk confirmed that the Germans were still in the same course and speed trying to get out of DS. No luck there: it was a tactical decision.

3. Hood's lack of good shooting. Hood was using the Dreyer table, which was unreliable whilst the Germans were using at the time high tech firing control. No luck there. It is also another technical issue.

4. Bismarck quick firing solution on Hood. That wasn't luck: they did a pretty good artillery work. PE also made a good one. That was not luck: it was good training and good performance.

5. That Bismarck hit that precise spot? Isn't it at the end what every artillery commander hopes to do? Is like to score a football goal: in order to broad your chances of scoring one you need to play better. The same principle.

If anybody cares to read Bruce Taylor's book on Hood and the accounts of the survivors prior to the fatal hit the situation on Hood wasn't that good: many hits were landing on Hood, they were not scoring a single one, Holland was trying desesperate way to open the firing angle, the spotting top was shot down, some butchery happened a the base of the tower, etc. It was a matter of time before something of sorts happened.

Why Bismarck's didn't blew up when 2,876 shells of various calibers were fired at her on 5/27/41? Because the space arrayed armor protected her vitals, something that Hood didn't have in the same degree. Those facts bother some people, so the "lucky" falacy is brought up, that's all.
An appeaser is one who feeds a crocodile, hoping it will eat him last.
Sir Winston Churchill
RobertsonN
Member
Posts: 199
Joined: Wed Jan 05, 2011 9:47 am

Re: late 1943 Tirpitz instead of Bismarck in May 1941

Post by RobertsonN »

Continuing with the theme of the randomness of hits it is interesting to consider what would have happened had the Hood received the hits suffered by POW instead.

The hits in the superstructure would have knocked out the main foretop FC and one AA FC position. The air burst over the midships area might have ignited some ready use ammunition and started a fire. The 8 in hit just aft of the citadel on POW would have probably hit the 12 in belt of the Hood (562 ft long belt v. 414 ft in POW). The 8 in detonation on the side near the steering gear would have likely been withstood by the 3 in HT plating.

The most crucial would have been the non-exploding underwater hit. The 1.5 in sloped TB (there were also four rows of crushing tubes) might have stopped it as in POW. But if it had not a shell would have probably not got as far as a boiler room; however, it might have penetrated one of the three engine rooms, which were wider.

So there might have been a significant drop in speed, as well as considerable topside damage. The main armament would still have been intact though, unlike in the POW. The Hood could have continued a while longer. Probably as with Exeter at the River Plate, she would soon have to withdraw because of damage and a list (The metacentric height on Hood was lower than in newer ships so side flooding damage would have been more likely to result in a significant list). In this scenario, however, she should have been likely to have scored a few hits herself, with a fair chance of a significant hit.

Had the action taken place much later than May 1941 the Hood should have benefitted from the new gunnery radar by then available. This appears not to have been used in the actual battle.
lwd
Senior Member
Posts: 3822
Joined: Sat Jun 17, 2006 2:15 am
Location: Southfield, USA

Re: late 1943 Tirpitz instead of Bismarck in May 1941

Post by lwd »

Luck is essentially a low probability event occureing. So
Karl Heidenreich wrote: ...
Let's see which part of it was "lucky":
...
5. That Bismarck hit that precise spot? Isn't it at the end what every artillery commander hopes to do? Is like to score a football goal: in order to broad your chances of scoring one you need to play better. The same principle.
Not quite. The Bismarck was clearly not aiming at that precise spot. Even if they were the probility of hittingit would be extremely low. So yes this is where the luck came in.
... many hits were landing on Hood, they were not scoring a single one,
Many" Certainly not from Bismarck and those from Eugen were unlikly to cause catastrophic damage.
Holland was trying desesperate way to open the firing angle,
"Desperate"? Certainly he reached a range where he wanted to bring his full battery to bear but that hardly qualifies as "desperate".
It was a matter of time before something of sorts happened.
Of not. Certainly the more fire she recieves the more likely such a hit is but Bismarck could have emptied her magazines without causeing a catastrophic hit especially the one under consideration.
Why Bismarck's didn't blew up when 2,876 shells of various calibers were fired at her on 5/27/41? Because the space arrayed armor protected her vitals, something that Hood didn't have in the same degree. Those facts bother some people, so the "lucky" falacy is brought up,
Given that she was low in the water and the British were firing from close aboard for the msot part it's not at all surprising that she didn't suffer a catastrophic hit. Her armor scheme would be part of the answer as well. The German use of fixed ammo would also contribute. Luck is hardly a fallacy though. It was a lucky hit that silenced half of Bismarck's main battery. It was lucky, although to a lesser extent, hits that destroyer her fire control, and it was a lucky hit that rendered her unstearable. [/quote]
that's all.
Not by a long shot.
Post Reply