Bismarck radar detector

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hans zurbriggen
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Re: Bismarck radar detector

Post by hans zurbriggen »

Hello Mr. RF,
I agree: fatigue and stress may have played a part in the wrong estimation done on board BS. For sure radar, radio and/or B-Dienst team made a mistake at 07:00 on May 25.


Hello Mr. Wadinga,
you write:
'... a proposed but unachievable piece of equipment was promised but not delivered.'
or a too new equipment was actually delivered, but with unsuitable specification (or without sufficient crew training).

hans
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wadinga
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Re: Bismarck radar detector

Post by wadinga »

Hello Hans,

And this superior specification "mystery" equipment is still not operational 18 months after it is supposed to have been installed in Bismarck? Lutzow, which is supposed to have had this superior spec system installed in June 1941 and spends a year with nothing to do after her second torpedoing, seems to have had the standard Metox/Sadir/Samos with its limitations against shorter wavelength radars at the end of 1942.

If the superior spec system had been installed, and worked over an enormous distance, and provided the convenient rationalization for Lutjens' "shadowing" message some have claimed, could no-one get it to work in the succeeding 18 month period on other Kriegsmarine vessels? More likely it was only ever an aspiration, made more urgent after Bismarck and Prinz Eugen had been sent out without one, which it was hoped to install in Lutzow before her ambitious ocean-raiding mission, but which never materialised. Rumours of this Kriegsmarine "wonder system" leak through to Schepke in the Air Ministry and he treats it as if it were reality. I believe we still do not have photo evidence of Lutzow with a Timor antenna in 1941.

All the best

wadinga
"There seems to be something wrong with our bloody ships today!"
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hans zurbriggen
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Re: Bismarck radar detector

Post by hans zurbriggen »

Hello Mr. Wadinga,
we don't know with certainty whether and what was deployed to BS. Hepke says it was Metox R203 (a non-military standard French equipment, according to Ludwig) or possibly a prototype built by NVK.
In summer 1941 probably Metox R600 (military standard) was deployed to big ships (ref. Hepke) together with Timor and Sumatra: the system could detect metric wl's (not under 70 cm). Evidence is available for Tirpitz in early September (https://www.kbismarck.org/forum/downloa ... hp?id=3891)
In 1942 we know (thanks again to Hepke's timeline) that Samos replaced Metox R600, using same antennas and able to detect wl's over 60 cm only.
In December 1942 Burnett used centimetric radars that escaped German detection, but this is another story and has nothing to do with BS. Germans solved this specific problem only in late 1943 / early 1944 (with Naxos/Tunis).

Problems with BS equipment could have been an excessive sensitivity (not necessarily larger bandwidth), detecting emissions whose power was far too low to get back to emitting ship and/or insufficient crew training in interpreting pulse strength (or fatigue/stress).

hans
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wadinga
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Re: Bismarck radar detector

Post by wadinga »

Hello Hans,
Problems with BS equipment could have been an excessive sensitivity (not necessarily larger bandwidth), detecting emissions whose power was far too low to get back to emitting ship and/or insufficient crew training in interpreting pulse strength (or fatigue/stress).
Excessive sensitivity has never been a problem, you merely turn down the gain. It doesn't matter whether you are tired or fresh as a daisy, there will always be a point where signal cannot get back to source. That is radar 1.01. Receiving radar impulses never means you have been located, merely that you may be. It is probably almost impossible to assess an absolute value of radar pulse strength, but I should imagine much easier to detect diminishing strength as the range from Suffolk extended from 11 to something like 70 miles during the early hours of 25th May. That is if there was anything aboard Bismarck which could detect 50cm transmissions, the likelyhood of which has also diminished rapidly toward zero.
In December 1942 Burnett used centimetric radars that escaped German detection, but this is another story and has nothing to do with BS
With respect, it gas everything to do with Exercise Rhine. Hepcke claims a specification for Bismarck in May 1941 which is unachievable for R203 or R600. He is so uncertain he says "probably" a Metox, contradicting his own knowledge of those systems, in other words he doesn't really know, and then this super specification is still unachievable 18 months later. Unachievable in Dec 1942 is the same as unachievable in 1941. Besides since we know Suffolk is using Type 284, how can Bismarck detect her pulses and count her shadowers when Kummetz cannot do the same 18 months later.

As I have pointed out previously, it is likely Holland used the same ploy as Burnett, refusing use of PoW's Type 281 and hoping for Type 284 coverage of the stern sector, showing he and his staff had a good grasp of the nascent art of electronic warfare. (This phrase was so good in my article, it has already been "stolen" by one published author.) :shock:

All the best

wadinga
"There seems to be something wrong with our bloody ships today!"
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hans zurbriggen
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Re: Bismarck radar detector

Post by hans zurbriggen »

Hello Mr. Wadinga,
we agree that British had a better tactical preparation in exploiting radar technology at hand.

I do not understand your Hepcke criticism however: he says exactly the same than Fricke in F.O. regarding the detectable wl's.
Both speak of wl's coverage 50-200 cm (that was not actually achieved until late 1942 - 1943). It's an 'error' (overestimation possibly from Metox technical specs https://www.kbismarck.org/forum/downloa ... hp?id=3897) we have not explained yet, but it shows Hepcke's knowledge of German radars and familiarity with KM 'secret' information too.
Until we do not have a better reference than Hepcke, I still think we should rely on his good paper and valuable timeline for German radars.

Coming to BS on May 25, sensitivity may not be a problem only if crew is trained to correctly interpret signal strength.
It's well possible that BS received her passive radar in mid May. Crew might not be sufficiently prepared to distinguish between a low (possibly even refracted) signal that cannot get back to an emitting ship and a strong signal. This would explain Lütjens 'mistake' regarding British shadowing.

hans
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