Bismarck at DS after the second turn

[Bill Jurens]

I am glad to see we are back on track again, and discussion is resuming. I was becoming concerned that interest had been lost.

I will make a few relatively brief comments for what they are worth.


Mr. Bonomi wrote:

"I hope that now everybody can check the official documents, I mean the Jasper report for the 15.000 meters distance between PG and PoW at 06:00 and the 2 PG maps for the 143° bearings and agree about this being the most accurate estimate we can make between the 2 warships, PG and PoW at a given time, I mean at 06:00.

After having done this check, I hope everybody will agree that using this common reference mark ( 143° bearing and 15.000 meters between PG and PoW at 06:00 ) we can put together the 2 tracks ( PG and PoW ) as I did on my example here above yesterday."

I have attempted this geometric maneuver, without much real success. If I 'pin' the two track charts together using this set of figures, there is no part of the British track chart that overlays upon the German version of the track chart at all. One very large problem is that according to the British, at any given time, e.g. at 0555 and 0600, the two British ships were more-or-less aligned east-west of one another, and according to the Germans, at the same times, the two British ships were arranged in a more-or-less on a north-south alignment. That's OK, at least on the British side; insofar as there seems to be little dispute about the alignment of the British ships in British sources, it's clear the Germans must be wrong. It's a bit -- one might even say a lot -- tougher looking at the German side insofar as Prinz Eugen's track chart shows nothing of Bismarck, meaning we really have no comprehensive track chart of the German side at all. I personally would consider hanging the entire construction on a single initial range and bearing set ( i.e. 15000 m at 143 degrees at 0:600) which itself is in some dispute on the German side, a very problematical exercise. I think we really would need at least two -- and preferably three -- strong undisputed anchor points to bring the entire relative position of the British and German track charts together. Linking them both together is where the problems lie...

So my bottom line, at least as things stand right now, is that I remain reluctant to accept Mr. Bonomi’s proposal for a single range and bearing set (which I read as 15000 m at 143 degrees at 0:600 from POW to PE) as definitive. Nor am I, at this juncture at least, able to provide a ‘better’ alternative. Schiaparelli saw canals on Mars, and few could provide a better explanation. But that didn’t make them real.

That does not mean that Mr. Bonomi’s proposal is not a good start – one really does have to start somewhere – nor that it is necessarily incorrect. It just doesn’t seem, at least to me, a strong enough foundation upon which to build an entire reconstruction. In that regard, I am hoping is that Mr. Bonomi, either alone or in conjunction with others, might be able to present at least a couple of additional sets of observations for bearing and distance that might help to pin down the track chart with a bit more precision. I don’t think that one set is really enough. I appreciate that Mr. Bonomi has probably explained all of this before, and commend him upon his patience should he wish to attempt to do do again. As one who spent many hours on both sides of the classroom lectern, I can assure him that sometimes only repetition will do the trick...


Wadinga wrote:

“I have speculated that although Jasper was getting correct range values a electrical transmission fault gave both Reimann and Brinkmann artificially high values consistently offset from the real value by 4100m. Can you shift the German plots of PoW's tracks 4100m along 323 degrees?”

Yes. I have tried that, again without much success. It helps, but the fact remains that the German and British depictions of the British ships are so remarkably discrepant regarding east-west and north-south relative positions that I can see no easy way to bring them into any sort of congruence. Your suggestion does, however, bring at least the ‘explosion point’ into better agreement. One could do the same by rotating the British and German track charts about 12-17 degrees. This maneuver brings the various plotted points into reasonable congruence, but would mean that all of the course information would have to be discarded. Taking the average error to be about 14 degrees would mean that one of the parties would have to have been 14 degrees ‘off’ in course readings, or that they would each have had to have been about 7 degrees ‘off’ in different directions. Not impossible, but unlikely. It’s also possible, but quite unlikely I think, that one of the track charts is really aligned to magnetic North rather than true North. I thought about this many years ago, but abandoned the idea as implausible.

I hope all find this useful, and even interesting...

Bill Jurens

[Algonquin-R17]

Hello Everyone,

Ok so I have followed and read all of the threads on this battle from the beginning. I openly admit that on a scale of 1 to 10 rating my knowledge of this event to those dedicated scholars driving this discussion I am about 0.5, less than 1. However that does provide me with a unique advantage, my mind is not cluttered with the myriad of conflicting information, I have no preconceived opinion to prejudice my judgement.

I do not have to continue to defend a previously upheld position.

When I read this, as posted by Wadinga,

Brooke Another salvo had just gone when I heard Guns warn his director layer 'Stand by to alter course to port'. This long-awaited move— presumably we were going back to the original heading so that 'Y' turret could bear for the first time—had begun to take place, in that we heeled to starboard and it became temporarily more difficult to hold the Bismarck steady in one's glasses, when the ship suddenly rolled upright again and then continued to heel over the opposite way; moreover, with the urgency and excessive vibration that comes only from violent rudder movement. We were going hard-a-starboard. Back towards the enemy again. What the hell was going on? There was a momentary lull. Probably the director gunner had been put off his aim, and in the comparative quiet I realised that hitherto there had been an intermittent background noise. The ship steadied up and there began to come back to port. Dick Beckworth said "my god! The Hood's gone!...

It tells me that Y turret had yet to bear, but was about to with the turn to port which had started but was interrupted by an aggressive turn to starboard to avoid the Hood's destruction.

This man's feet were on that vibrating deck, he is an eye witness, he has no reason not to tell the truth and it supports what I believe is a logical explanation of the avoidance maneuver by POW. In addition to the other corroborating observers noted by Sean.

In my own opinion, for what it is worth Wadinga has the trump card on this specific point. I cannot get past this statement and I do not feel that the salvo plot is an adequate defense.

Bob

[Bill Jurens]

I thought it potentially useful to append a copy of a track chart which is, at least to my intention, in accordance with Mr. Bonomi's suggested benchmark of using the 0:600 distance and bearing from Prinz Eugen to P.O.W. as a starting point.

As both British and German tracks are to the same scale, and oriented to True North, It also allows users to -- using a bit of transparent or translucent tracing paper -- trace over the individual tracks and attempt to superimpose them using alternative, and potentially 'better' hypotheses.

Bill Jurens

[Bill Jurens]

My apologies for the second posting. This supplements my immediately previous post, which alluded to a track chart plot which -- for whatever reasons -- appears not to have actually gone through. It is attached here for reference...

Bill Jurens

[Alberto Virtuani]

Hello everybody

Byron Angel wrote: "I have re-visited the A arc question and discovered a logic error on my part...Based upon McMullen's diagram and recorded bearings, Bismarck would have been with PoW's A arc on any compass bearing =/> 325 degrees."
Wadinga wrote: "Byron... witnesses say the A arcs remained closed. "

Thanks to Mr.Angel for his fair confirmation of my calculations: at 6:00 any bearing >325° would have allowed Y turret to bear and to (theoretically) fire, while on course 280°. Any bearing less than 325°would have prevented fire while any turn against the enemy would have immediately wooded Y turret (the margin was 5° at 6:00), that never happened.


Regarding Mr.Wadinga attempt to say that Brooke or Brinkmann witnesses (based on their personal feelings / optical observation from 15 km) are more reliable than the official PoW salvo plot and GAR, I have already explained that the hard movement of the rudder to starboard (when Hood exploded) initiated a rolling movement that was felt (and seen) by everybody but that did not change much the course of PoW, because there was an immediate counter-order to the helm (as per Rowell map http://www.hmshood.com/history/denmarks ... encIVb.gif).

This is a fact: the PoW salvo plot + GAR (plus Mr.Barben's report (Vickers Armaments) that gives us even the number of shells fired by each turret/gun) confirm that Y turret never wooded again after salvo 9 (official records and mathematics prove this fact viewtopic.php?f=1&t=8335&start=135#p81455), thus there was no relevant turn against the enemy at all, even if witnesses say so.
If someone has another explanation of the way to read the PoW GAR (http://www.hmshood.org.uk/reference/off ... 09guns.htm), please present it, else it simply means that all the witnesses (British and German, including Rowell himself, who exaggerated the shape of the "turn against the enemy" in his map to make it slightly more evident) got just confused by the ship violent rolling movement and that PoW never got on a course more northerly than 285°/295°because turret Y was firing her salvos uninterruptedly every 20 seconds at 6:00.

I leave to someone more expert than me to calculate exactly how many max degrees PoW could have turned (and counter-turned) within 20 seconds timeframe...


Bye, Alberto

[Antonio Bonomi]

Hello everybody,

@ Wadinga,

you wrote :

This shift is remarkably similar to the 4100m consistent error in much the same orientation identified (by Antonio) as the error between the values Brinkmann and Reimann both recorded and that which Jasper had for 06:00. I have speculated that although Jasper was getting correct range values a electrical transmission fault gave both Reimann and Brinkmann artificially high values consistently offset from the real value by 4100m. Can you shift the German plots of PoW's tracks 4100m along 323 degrees?

Thanks.

@ Bill Jurens,

thanks for the prompt realization of a map that now is in line with my suggestion about the PG to PoW bearing ( 143°) and distance ( 15.000 meters ) at 06:00.

Now my suggestion :

Antonio_Bonomi_maps_merged_143_15000_meters_PG_vs_PoW.jpg (17.09 KiB) Viewed 2577 times

Is correctly translated into your example :

Bill_Jurens_track_chart_one_example.jpg (14.67 KiB) Viewed 2577 times

As I have anticipated and you have suggested to everyone, ... now we have a real reference base to work with based on the best available maps being merged using an available and evaluated connecting factor, ... I mean the PG real bearing to PoW available on 2 maps and the distance at 06:00 taken from the PG gunnery officer evaluations.

You may have noticed that now where the Bismarck was behind the Prinz Eugen on her starboard side and how she closed in from her 05:53 position until the 06:00 position is well visible also on the graphic format.
This confirms the speed delta between Prinz Eugen at 27 knots and Bismarck sailing behind her at a faster speed.

I think that now we need to :

1) first of all to check and verify the speed and the timing marks on the various already available tracks.
I mean the Prinz Eugen marks on her track that must be one every 833 meters ( sailing at 27 knots ) and one every 864 meters ( sailing at 28 knots ) as far as PoW and Hood.

2) add backwards the missing tracks piece for PoW and Hood until 05:20 with the various executed turns ( 240 -> 280 -> 300 -> 280 ).
Do the same for the Prinz Eugen with the known information from her map and her KTB ( Kriegstagebuch = War Diary ).

3) Add a line in parallel ( in line of battle ) to Prinz Eugen on her starboard side from 06:00 backwards. This will be our Bismarck reference track to be verified with the additional information.

4) Check the various available bearings among all the units starting from the " Enemy in sight ! " radio message ones of Hood and PoW and double check them with the available Prinz Eugen ones, until the 06:00 battle time.
I am sure that now the PoW gunnery plot bearings toward the Bismarck line we will have tracked in parallel to Prinz Eugen on her starboard side following the German cruiser in line of battle, will be subject of a very careful analysis of course.

As a personal suggestion to everybody I would like to ask to all of us to concentrate our attention to the battle time from 05:20 until 06:00 for the moment and forget for a while about what happened after.
This will allow a real productive team work and a solid reasoning base.
I m sure we will have plenty of time once done with this initial part, to do the same for the battle time from 06:00 after, until 06:30.

Bye Antonio

[Byron Angel]

Two comments -

> Avoidance Turn by PoW
Interpreting McMullen's graphical plot of PoW's salvoes, salvo 16 was fired at approximately 0600:45 and salvo 17 was fired at approximately 0601:40. That suggests an interval of approximately 50-55 seconds between discharges.

> Bearing and heading discrepancies
Is it certain that all the recorded bearings were corrected for true north ..... just asking. If not, the deviation would have been considerable at such a high latitude.

B

[Antonio Bonomi]

Hello everybody,

@ Bryron Angel,

Yes, they were all using ( T ) true north bearings. Only the Germans on some data where using relative to their course bearings as far as I recall.

Basically now we need to realize in large scale, check and control this part from 05:20 until 06:00 battle time :

0520_until_0600.gif (14.23 KiB) Viewed 2543 times

I used my old 2005 battle map tracks to provide an example.

Bye Antonio

[Alberto Virtuani]

Hello everybody,

Byron Angel wrote: "salvo 16 was fired at approximately 0600:45 and salvo 17 was fired at approximately 0601:40. That suggests an interval of approximately 50-55 seconds between discharges."

Correct, but once we accept 06:00 as the proposed "starting point" (Hood explosion), we should look at salvos 14 to 16 (all fired at 20 seconds intervals) max as the ones affected by a possible emergency "avoidance maneuver" that could have had an effect by 6:00:20 - 6:00:30.
By the time salvo 16 was fired, PoW was already alongside Hood remains: having been 670 meters (= 740 meters * cos 25°) behind, she would have been perfectly aside Hood at 6:00:45, when clearly no avoiding maneuver was needed anymore).

No relevant turn to starboard could have been done between 5:59:30 and 6:00:45 by PoW, confirming the salvo plot and what is written in the GAR, with Y turret continuously bearing on enemy after salvo 9.


Bye, Alberto

[Bill Jurens]

I think we may be getting ahead of ourselves here. My posting of "Track Chart One" should not be interpreted as some sort of acknowledgement that I think it to represent a correct solution or a suitable jumping-off point. It was merely posted to illustrate what Mr. Bonomi's proposed benchmark distance and bearing set looks like when all track charts are included, including the residual portions of the German track chart that have been omitted in most other plots. So, although Track Chart One has been forced to match at a single point, it's very important to note, at least in my opinion, that it really does not match very well at all, at least with the German track charts of the British courses, etc. at any other points. Put in a simpler way -- and to take just one example -- why might we assume that a range of 15000m and an angle of 143 degrees is correct, while at the same time rejecting what might be an apparently equally valid solution of taking the accurate range to be equal to 15000+3531=18531 meters instead? That is why I suggested in an earlier post that we actually do need some additional corroborating evidence, perhaps expressed in tabular form, that would help to support the 15000m range, etc. These could be expressed in the form "time, range, bearing, observing ship, ship(s) being observed, instrument(s) used, and source material."

Regarding the turn(s) of Prince of Wales at around 0600, it is my opinion that they were indeed fairly radical; almost certainly much more extreme than the rather gradual turns shown in the German track chart. The configuration of the British ships prior to the 'final turn' of Hood, which her rudder shows must have been at least in progress when the ship was destroyed, was -- or appears to have been -- to essentially bring the two British ships into 'line ahead' formation with A arcs open. This means that had Prince of Wales continued the turn she would have in effect run directly into the wreck of Hood. This required prompt action, particularly as the distance between the two ships was not great, and Hood probably stopped forward motion much more quickly than seen in any normal maneuver experienced before. The helmsman had to first check the (probably) already started turn to port and convert it in to a rather extreme turn to starboard, after that coming to port again in order to open the A arcs again. Not conducive to good gunnery, especially after German shells began to come aboard, likely while passing Hood.

Best from here...

Bill Jurens

[Antonio Bonomi]

Hello everybody,

@ Bill Jurens,

in order to verify if we are going the right direction or not with the 143° True bearing at 06:00 between PG and PoW at the 15.000 meter distance, I suggest you to do the checks I listed above.

Only after having realized the correct tracks in scale for course and speed for all the 4 main warships do this bearing control for verification and confirmation.

I mean this next one with the well known 4 bearings taken by the British warships toward the German squadron.

A) At 05:37 PoW enemy in sight signal with the enemy on bearing 334° True.

B) At 05:44 PoW repeating her radio signal with the enemy this time on bearing 335° True.

C) At 05:43 the Hood enemy in sight radio signal with the enemy on bearing 337° True.

D) At 05:53 PoW open fire on Bismarck on bearing 335° True.

0520_until_0600_bearings.jpg (44.81 KiB) Viewed 2487 times

This is in my personal opinion the only way to define correctly the 4 main tracks knowing their course and speed, and adjust them one versus the other on the battlefield realized in this way.

Using the bearings and forgetting about the distances for a while, ... because the bearings are the first thing to be adjusted in priority, using the correct realized tracks for known course and speed of the warships.

The distances can be evaluated later on, ... and I can anticipate you that we will realize that all the distances have been over estimated by everybody especially at the beginning.

To be noted that Prinz Eugen course and speed is very easy : 220° True and 27 knots all the way thru from 05:37 onward for those 4 verification.

The variables are the 2 British warships ( especially the turns ) during the 3 course changes and the Bismarck speed ( not the course that will result being 220° True ). Those are the variables and the parameters that we are going to be working on.

NOTE : I have never evaluated the BC1 speed lost caused by the 3 turns.

Bye Antonio

[Alberto Virtuani]

Hello Mr.Jurens,

you wrote: "The configuration of the British ships prior to the 'final turn' of Hood, which her rudder shows must have been at least in progress when the ship was destroyed, was -- or appears to have been -- to essentially bring the two British ships into 'line ahead' formation with A arcs open..."

I disagree with the above statement:
Leach, in his narrative, says that the flag ordering the 20°to port turn was still flying when Hood exploded:

Leach_Second_turn.jpg (23.57 KiB) Viewed 2473 times

and Rowell is crystal clear saying that Hood exploded before the second 20° turn "could be executed" (http://www.hmshood.org.uk/reference/off ... htm#Rowell, point 33), at least for PoW. Nobody stated otherwise (except the ones who confused the first with the second 20° turn...).


I have no reason to doubt about what you say about the rudder of the wreck. However, if Hood had already the rudder turned (that doesn't mean anyway that the ship had already started turning herself, even if Hunter Terry says that she was actually turning to port after the explosion, but this can be the result of the water drag, http://www.hmshood.org.uk/reference/off ... .htm#Terry, point 53), it just means that the helmsman got the order and executed it before the flag could be lowered for PoW to do the same.


Bye, Alberto

[Bill Jurens]

My thanks to Mr. Bonomi for the additional bearing and distance data. I will plot these as soon as possible and see if they, at least in my mind, confirm the plot suggested by the 15000 meter 143 degree data. I suspect they will at the very least help to clarify the situation.

Addressing Mr. Virtuani's point, as I am sure he knows, there has been, over the years, considerable discussion and debate as to whether or not Hood effectively commenced the final turn of 20 degrees to port. What follows, for what it is worth, are my own feelings on the issue. Experienced helmsmen (and captains) are pretty good at these things, and I would not be surprised that -- insofar as the degree of turn was already known from the 2 Blue flag flying on Hood -- that the helm on Prince of Wales was put over upon sighting the 'knuckle' at Hood's stern when she put her own rudder over. There is really no reliable data on whether the commencement of Hood's turn was simultaneous with the flag signal; it might well be that the 'execute' order aboard Hood was given, and undertaken, before the flag signal was actually completed, or that -- for whatever reasons -- there might have been a deliberate delay imposed in order to slightly change the relative ship positions after the turn was completed.

We have examples from the British side which are, at least superficially, contradictory, i.e. the rather complete narrative given earlier in this thread, which implies at least a fairly aggressive turn vs the notation that "Hood had a further 2 Blue flying...", which suggests that P.O.W. might not have begun the turn to port at all. Although my sense of things is that the overall weight of the evidence would suggest a rather dramatic set of maneuvers on the part of Prince of Wales, in point of fact it would appear that the various descriptions given (on both sides) cannot all really be reconciled completely, leaving any reconstructed track at least somewhat conjectural. The key is that one cannot reduce the accuracy of further conjecture by adding additional data that may be more precise or reliable. A chain, in reality or in epistemological terms, still remains only as strong as it weakest link(s).

Along with so many other issues regarding this particular action, this remains, at least in my mind, one area where honest and intelligent men can disagree initially, but where further discussion may lead to eventual reconciliation.

Bill Jurens

[Alberto Virtuani]

Hello Mr.Jurens,
I agree we have several contradictory statements in this regard and I also do agree that the weight of evidence points to the fact that PoW never started the second turn to port, as confirmed by the two senior officers present in the compass platform of PoW, both in agreement that the turn was never executed.

Regarding the violent maneuvers of PoW, even without the initial 20° turn to port (that would have been quite smoothly executed anyway), the rudder put hard to starboard at full speed and the almost immediate counter-turn to port, even if not affecting her course in a very relevant way, are more than enough to explain a remarkable rolling, not to speak of the 160° turn at full speed executed 1 minute later.


Bye, Alberto

[Antonio Bonomi]

Hello everybody,

@ Bill Jurens,

very good, I am sure that it is going to be a very interesting work.

Here the evidence just for the record.

The BC1 warships radio messages :

Initial_bearings_BC1_to_German_squadron.jpg (36.99 KiB) Viewed 2391 times

The PoW gunnery bearings with her open fire one :

PoW_open_fire_bearing_335_at_0553.jpg (57.02 KiB) Viewed 2391 times

I like to remind everybody to evaluate also a very good Herr Nillson evaluation about the BC1 tracks he made time ago :

Herr_Nillson_evaluation_BC1_track.jpg (59.95 KiB) Viewed 2391 times

Herr Nillson evaluation on how from PoW they may have seen the 220° straight track of Bismarck, ... correlated to the PoW change of course as probably happened in reality, ... does deserve a careful analysis.

This verification is what needs to be done as best as we all can, using the bearings and not the distances.

Just my personal suggestion of course.

Bye Antonio