Barr & Stroud Dreyer vs. German Zeiss

[Tiornu]

"It should also be pointed out that the author of the critique cannot by any stretch of the imagination be considered impartial in the debate."
We all had a good snicker at the blooper by JMH, asking Sumida to write a review of a book that was, in effect, a rebuttal to Sumida's work. I'm sure it was an oversight. In defense of JMH, they then allowed Brooks to write a response to the review, and then a response to the response by Sumida.
The book is definitely recommended and credible, though it made my head spin when it got deeply into the engineering. Me, as far as engineering goes, I still stand in awe of the doorknob.

[marcelo_malara]

Thanks!!! Did you say too that there is paperback of Brooks´ book? Can you tell the ISBN, as I can´t find it at amazon.co.uk?

[tommy303]

Hi Karl,

The Admiralty Fire Control Table or AFCT, was essentially a whole new design since the last mark Dreyer, as in Hood, had taken Dreyer's original design to its mechanical limit. The AFCT in its successive marks provided for important automatic input, thus minimizing operator errors. If I recall correctly, the AFCT, being electro-mechanical, was a better system for continuous tracking and firing while manouvering compared to the Dreyer. The same could be said of the German and American systems (Schusswertrechner c/38 and the Rangekeeper/stable vertical). One can say the AFCT did the same things pretty much as the Dreyer, only it did them faster and more accurately; it was also better able to cope with rapidly moving targets.

To partially recap part of Sumida's critique, which I didn't realize was a restricted link, part of the problem was due to differing opinions within the Admiralty--ie Fisher and his followers with radical new ideas versus more conventional and conservative officers. Fisher had been more than willing to accomodate Pollen to achieve an end--ie a superior fire control system for ships which were becoming both more heavily armed and faster than before, even if it meant bringing the admiralty into research and development partnership by underwriting the work of an inventor as opposed to the more standard Laissez-faire procurement of finished or near perfected goods. Pollen, who was not in a financial position to fund his own R&D required this arrangement.

For a while, therefore, the Admiralty was using more than one procurment policy, but only as long as Fisher was in control (1904-1910, 1914-1915):

The fundamental cause of the breakdown of cooperation was the absence of consensus within the Admiralty on Fisher's radical strategic, tactical, and technical agenda. Division at the top on matters of strategy, tactics, and capital ship design meant that Pollen's concept of a fully automatic and therefore expensive approach to fire control, and the novel cooperative business agreement, were exposed to opposition from those who argued that manual, or later semiautomatic, methods were adequate to the tactical requirements of battleships operating in large fleets, and who also objected to the violation of conventional procurement procedures. The tactical implications of the emergence of a unilateral German threat in home waters also weakened the case for Fisher's concept of the battle cruiser and Pollen's vision of advanced fire control. It was these large factors, not just shortcomings in character and political errors on Pollen's part, which damaged and then destroyed cooperation.

In the end, Dreyer's table won out largely because it could be produced as is with technology and devices already in existance, while Pollen's was still more of a promise than a reality, and although it could have eventually been developed, its expense in both money and time were at odds with the Admiralty's preceived immediate needs.

[Tiornu]

Fisher also became convinced that the the Dreyer device could beat the pants off of Pollen--that's my eloquent wording there, but Brooks does give a direct quote from Fisher to that effect. Of course, that was only at one point in time.

[mike1880]

And of course Pollen was prepared to use the threat of publishing defence secrets if they didn't pay him large amounts of money, which even in the world of defence contracting is stretching the ethical boundaries somewhat.

Mike

[Tiornu]

Thanks!!! Did you say too that there is paperback of Brooks´ book? Can you tell the ISBN, as I can´t find it at amazon.co.uk?

It's there.
0415407885

[marcelo_malara]

Thanks!!!

[Karl Heidenreich]

Thanks tommy303. I enjoy the info.

Best regards

[Thorsten Wahl]

Very old thread but here is some useful information on the accuracy of optical rangefinding
achieved results of Panzerschiff Deutschlöand during 1st half 1937

[dunmunro]

Very old thread but here is some useful information on the accuracy of optical rangefinding
achieved results of Panzerschiff Deutschlöand during 1st half 1937

Thanks for the info, but unfortunately the image is very highly compressed and the text is no longer legible. Can you translate the column headings or decrease the jpeg compression setting?

Thanks

[Thorsten Wahl]

hires
hint each line is representing the result from measurement series of 30 or so individual measurements

10 U... 10m Basisgerät
6 U ... 6m Basisgerät
3 U ... 3m Basisgerät

as you can see they also conduct long range as well as short range training

and a exercise

[dunmunro]

hires
hint each line is representing the result from measurement series of 30 or so individual measurements

10 U... 10m Basisgerät
6 U ... 6m Basisgerät
3 U ... 3m Basisgerät

as you can see they also conduct long range as well as short range training

and a exercise

So they were claiming 34m accuracy from a 3 metre RF at 48300 meters range, while wearing a gasmask, under hazy conditions and 12m accuracy under good conditions?

I am not sure how to interpret the data presented, but it does not represent actual RF accuracy.

[Thorsten Wahl]

seems to me its an pointerror, probably 4300 m, even the Kriegsmarine is not free of errors