Bismarck at DS after the second turn

Discussions about the history of the ship, technical details, etc.

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wadinga
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Re: Bismarck at DS after the second turn

Post by wadinga » Fri Jan 11, 2019 12:32 pm

Hello Alberto,

Rowell's map shows a near instantaneous turn of 20 degrees at most taking 30 seconds. Have you ever turned 20 degrees in 30 seconds in your naval career? At 28 knots?

Here is where you can go to expand your knowledge about "derivazione" in locations where the Littorio class never went. eugeneleeslover.com/USN-GUNS-AND-RANGE-TABLES/USN-GUNNERY-AND-FIRE-CONTROL.html

British shells are as susceptible to atmospheric density variations and rotation of the earth in high latitudes as American ones.

Your refusal to accept the limitations of the available data and therefore the "correctness" of any speculation created from it, means you are correct in one thing
this discussion is a waste of time.
All the best.


wadinga
"There seems to be something wrong with our bloody ships today!"

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Alberto Virtuani
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Re: Bismarck at DS after the second turn

Post by Alberto Virtuani » Fri Jan 11, 2019 2:03 pm

Hello everybody,
Wadinga wrote: "Rowell's map shows a near instantaneous turn of 20 degrees at most taking 30 seconds. Have you ever turned 20 degrees in 30 seconds in your naval career?"
Where/how is Mr.Wadinga able to measure 30 seconds on Rowell's map ? :think:
Can he fill the table (if able) with his speculation about Holland having turned his ships with hard rudder (while not loosing speed/bearing was essential) ?
PoW turned 160°at full speed and hard rudder in less than 2 minutes.... Why should we assume "hard rudder" to turn 20° even in 10 seconds ? :think:
he wrote: "Here is where you can go to expand your knowledge about "derivazione" in locations where the Littorio class never went."
Many thanks. He can now fill the table with his alternative proposal to show us that he was somehow able to understand what he has read....



For the time being, after comparing Antonio's and mine, I would now propose these values:

Tab_Legs_V2.jpg
Tab_Legs_V2.jpg (77.61 KiB) Viewed 294 times

If Mr.Wadinga is able to propose something different, we can discuss, if not, we can all live with Antonio's complete reconstruction forever, waiting for someone else input.
For sure this battlefiled area base evaluation cannot be denied, it can just be made more precise in its detail measurments: download/file.php?id=3359.



Bye, Alberto
"It takes three years to build a ship; it takes three centuries to build a tradition" (Adm.A.B.Cunningham)

"There's always a danger running in the enemy at close range" (Adm.W.F.Wake-Walker)

Bill Jurens
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Re: Bismarck at DS after the second turn

Post by Bill Jurens » Fri Jan 11, 2019 6:46 pm

Let's all try to back off from the personal comments and slurs again. As before, they do nothing but antagonize the target, and if anything push the discussions backward rather than forward.

It IS pointless -- at least in my opinion -- to involve ourselves in quibbles about turning rates and small variations in ballistics when we have not, at least so far as I know, even established what we are arguing ABOUT.

I presume, in that regard, that we are attempting -- by whatever means -- to reconstruct a reasonable track chart for the Denmark Strait action, This would first require that we at least collate, and hopefully agree upon, what might constitute primary evidence. Only after that has been done, might we begin the process of trying to determine exactly what can be deduced from that bank of primary evidence.

So we have two steps. The first is accumulating the raw data. The second is deciding exactly what, if anything, that raw data -- which is admittedly incomplete and sometimes contradictory, might be able to tell us.

Start with step 1. Assuming that the geometry represented by the diagram showing legs A through G is accepted by all as representing at least a plausible jumping-off point for further discussion -- one has to start somewhere -- the next phase would be to collect and analyse all of the data available to establish the characteristics, in navigational terms, of each of the legs depicted on the diagram. In that regard, we might consider whether or not another geometry, e.g. one beginning with an alternative for leg A would be more appropriate. This will be easier for some legs than for others. For legs C and D for example, there seems to be only a single source of evidence, which implies they are not debatable. That incidentally does not suggest they are correctly defined, only that there are no alternatives to be considered. A blunder in recording the length or bearing of Leg C, for example, would be difficult to detect.

It is only after we have discussed the validity of each individual leg in detail, and established the limits of the accuracy and precision of each individual leg, that we can begin to assemble our collection of 'best guesses' into a coherent overall geometry. That geometry is unlikely to be geometrically coherent, and the resolution of that residual incoherence -- if such is possible at all -- represents a further stage in the process.

We did have a few discussions regarding the length and bearing of Leg A, but soon drifted away from that. I think that it would be best if we tried to return to that issue, and that issue alone, and see if we can determine to what degree of accuracy Leg A can be reconstructed. This, of course, requires a full discussion of exactly how the length of Leg A can actually be derived. Leg A DID exist, i.e. in real life the there was a precise range and bearing between Prinz Eugen and Prince of Wales at 0557. The question revolves around whether or not sufficient data survives to enable us to reconstruct that particular leg to any useful degree of accuracy and precision. Only then might we move on to attempting to resolve the lengths and bearings of other legs in the geometry set.

Again, I'd ask participants to PLEASE refrain from personal attacks on other correspondents. One can attack the observations, but additional editorializing regarding the motives and intelligence of other participants is both unnecessary and inappropriate. Our eyes, at least at this stage, should be on the primary source evidence and the evidence alone.

I hope we can all agree on that, at least...

Best from Winnipeg...

Bill Jurens.

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Antonio Bonomi
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Re: Bismarck at DS after the second turn

Post by Antonio Bonomi » Fri Jan 11, 2019 8:26 pm

Hello everybody,

@ Bill Jurens,

at this point we have given everybody enough time to provide any value add on both the base map as well as on the table you have proposed.

The current results are no changes being suggested to the base map diagram and the table me and Alberto has produced after few exchange of distances.

I think it is a good enough point to restart and move forward now, because in any case future small changes will occur no matter what.

As I have already written time ago, now we can only draw the Bismarck and apply the PoW gunnery bearings in order to obtain both the Bismarck timetable of her positioning while sailing on course 220°T as well as the most correct legs dimensions and turns positioning on the BC1 warships.

My personal suggestion is to start from the 06:00 Bismarck and PoW positions, ... with Bismarck on 330°T and at 15.042 or 16.450 yards from the PoW, ... and than move backwards until the 05:37.

In easy words we have to apply this approach to the base reference map we have realized :

Herr_Nillson_evaluation_BC1_track.jpg
Herr_Nillson_evaluation_BC1_track.jpg (59.95 KiB) Viewed 251 times
Not so difficult to realize it in the exact scale and put it on top of what we already have made, ... with the correct timing references.


Bye Antonio
In order to honor a soldier, we have to tell the truth about what happened over there. The whole, hard, cold truth. And until we do that, we dishonor her and every soldier who died, who gave their life for their country. ( Courage Under Fire )

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Antonio Bonomi
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Re: Bismarck at DS after the second turn

Post by Antonio Bonomi » Sat Jan 12, 2019 9:20 am

Hello everybody,

@ Bill Jurens,

here the Bismarck ( GREEN dot ) correctly positioned on bearing 330°T at 15.042 meters ( 16.450 yards ) from the PoW at 06:00.

I have re positioned closer to PoW the Prinz Eugen track and position at 06:00 ( BLUE dot ), so the Bismarck will result being correctly on the heavy cruiser wake sailing in line, a bit on her starboard side as it must be.

Map_with_Bismarck_at_0600_resized.jpg
(81.32 KiB) Not downloaded yet

and here the modification detail :

0600_detail_German_warships.jpg
0600_detail_German_warships.jpg (32.79 KiB) Viewed 201 times

in this way we have the Bismarck track in the map correctly positioned as a starting point.

The PoW gunnery plot will define the Bismarck real speed and movements on her 220°T course, ... in relation to PoW while following the Prinz Eugen, ... and the BC1 warships most correct legs definition.

Bye Antonio
In order to honor a soldier, we have to tell the truth about what happened over there. The whole, hard, cold truth. And until we do that, we dishonor her and every soldier who died, who gave their life for their country. ( Courage Under Fire )

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Alberto Virtuani
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Re: Bismarck at DS after the second turn

Post by Alberto Virtuani » Sat Jan 12, 2019 11:27 am

Hi Antonio,

I don't see your positioning of Prinz Eugen as the most correct one, for the reasons I have explained here (viewtopic.php?f=1&t=8335&start=345#p81831).

We have to consider that the PoW gunnery plot shows salvo 13 fired at 5:59:45 from 15042 meters (16450 yards) and that this "distance" is the distance of the "future point" of Bismarck, when the shells land, at around 6:00:10 (flight time was around 25 seconds for the British 14" shell at that distance).
As Bismarck was closing range by around 800 meters per minute due to the geometry of the engagement, her actual distance from PoW at 5:59:45 could still have been a bit more than 15400 meters and thus around 15200 meters at 6:00:00.
In order to keep PG in line with BS (or very slightly to her port side), PG could still be at around 14800 meters from PoW at 6:00:00, around 400 meters closer to enemy, preceding the flagship by 1500-2000 meters.

Putting PG at 14250 meters from PoW at 6:00:00, will be too close and would deny what Jasper says in his report.
I would not keep PG much less than 14800 meters from PoW at 6:00:00.


Bye, Alberto
"It takes three years to build a ship; it takes three centuries to build a tradition" (Adm.A.B.Cunningham)

"There's always a danger running in the enemy at close range" (Adm.W.F.Wake-Walker)

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Antonio Bonomi
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Re: Bismarck at DS after the second turn

Post by Antonio Bonomi » Sat Jan 12, 2019 1:04 pm

Hello everybody,

@ Alberto Virtuani,

I agree with you my friend, ... my one was just a graphic example, ... so everybody can understand just like you did, ... what I mean as a process of realizing this battlefield in the most correct way given the available data we do have today.

Your data are the most reasonable ones.

Bye Antonio
In order to honor a soldier, we have to tell the truth about what happened over there. The whole, hard, cold truth. And until we do that, we dishonor her and every soldier who died, who gave their life for their country. ( Courage Under Fire )

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