HI Dave Saxton, JtD and lwd!
Thanks for your responses to my comments about "first operational use of radar"
and the relative vulnerability of
Bismarck and
Hood to lucky hits. Here's some additional explanation and/or clarification of my comments in light of your responses.
Dave Saxton - Operational Use Of Radar
Dave notes:
It was not the first operational use of radar.
. . . . . . . . . . . . .
It was the first use of Type-284 by the British. The British had used radar a few months previously in the Med against the Italians. In that case it was Type 279.
Actually it was the first operational use for shadowing, according to Rear Admirral Wake Walker's After Action Report:
10. This was, I fancy, the first occasion that R.D.F. has been used for shadowing and the supreme value of it for this purpose cannot be over emphasised. Suffolk made good use of it but I think the long ranges she obtained during the day must have made her a little over-confident during the night when she must have been near the limit of the R.D.F. range. This left no margin to cover a sudden change of course of the enemy such as was likely during the dark hours. Unless it brings the shadower within effective gun range of her quarry, it is considered that at night touch should be kept within 25 per cent of the ascertained R.D.F. range in hand.
Captain Ellis of
Suffolk calls its use to shadow at night experimental:
29. 0306 (B). Re-established Type 284 contact. No change. Zig-zagged 30° out for ten minutes, and back, during which time Type 284 contact was lost.
30. 0326 (B) - 0401 (B). Searching towards enemy's last bearing, until it became certain he had either turned round to starboard and worked eastwards under the stern of the shadowers, or he had altered course south-westward to draw ahead and away. This took rather long to conclude, partly because of the onset of fatigue (Suffolk have been steaming at considerable speed either in pilotage waters or following the enemy for four consecutive nights), and partly because night R.D/F tactics were still only experimental.
These first hand accounts were good enough for me to conclude that Tovey and Holland would not hang their hat on this unknown. Plus as you pointed out, they had a good idea ahead of time that its effective range was only 25,000 yards. The key to my alternate plan was that the risk of losing contact would be much less if
Hood and
PoW added their radars to
Suffolk's. A 25% safety margin would be close enough for
Bismarck to visually identify them and then use her known speed advantage to outrun the effective gun range of their radar.
As to German Radar:
The Germans had been using it operationally from day 1, and had operational radar that was quite capable and surprisenly sophisticated from 1938.
. . . . . . . . . . . . . .
The German Seetakt radar in 1941 could track capital ships to 30km.
Here's what Wake-Walker said about it.
9. I was always wondering if the enemy were using R.D.F. to locate us, but I have the feeling that his R.D.F. is linked with his gun control and does not search independently. Otherwise the cruiser should have been prepared for us at 2030 on 23rd and on various other occasions when clearing visibility brought us in sight at ranges from 8 to 13 miles. That he does fire at unseen targets is shown by the experience of the aircraft and destroyers when actually fired at under those conditions.
Apparently it wasn't very impressive.
JtD - Bismarck Lucky Hit
While I think you are exaggerating a bit . . . . . .
. . . . . . . . . . . .
I don't think Bismarck would just fall apart beyond repair on her own,
I was exaggerating to be funny, which you appreciate, given your wink about my BMW comment. Here's a more sober analysis.
Your general view is that before Denmark Straits Holland didn't have enough information about
Bismarck to assess her vulnerability to being crippled or sunk by one lucky hit, so he had to assume it was about the same as his ships.
In addition and setting aside assumption in favor of facts, she wasn't so toughly built to give her some special exemption from a lucky hit. lwd points out that after Denmark Straits the ship received the worst pounding ever by big naval guns and the hull was still afloat, as evidence that she wasn't vulnerable to such a lucky hit.
Both points illustrate something Holland didn't know at the time he would have while weighed whether to engage or shadow, and how lack of knowledge favors engaging. They differ on how tough Holland's target actually was, but I think they can be reconciled when you realize Holland's real issue - whether
Bismarck's ability to sustain battle damage without being sunk or operationally crippled, compared to that of his ships, was so superior that the odds are affected? He would be thinking about how resistant she is to decisive battle damage; sinking her with a lucky hit is one of the ways to do that, but he needs hits that damage or destroy essential functions that her mission or getting home require.
Basically, you have to separate the hull and deck citadel from the upper works, vulnerability of each essential function from its reliability, and sinking by gunfire from decisive battle damage by gunfire.
1) The compartmented hull, its armor and the deck armor make sinking an order of magnitude more difficult that any other ship, as well as decisive battle damage to the power plant and magazine functions in the citadel (it's almost immune to gunfire and requires torpedos to sink).
2) The hull and deck do not protect functions in the hull outside the citadel (fuel storage, steering, propellers and shafts) from decisive battle damage any better than any other ship. One lucky hit or more likely several hits can impair or destroy these functions and make the ship unable to do its mission or get home.
3) The upper works do not protect its functions (navigation, command, weapons, direction, detection, communications) from decisive battle damage any better than any other ship. If I recall correctly, certain defects (location of wires?) made some of these upper work functions more vulnerable than those of other ships to impairment or destruction by one lucky hit. Other functions like the guns require a number of hits, but one or more could make the ship unable to do its mission or get home.
4) As to 1, 2 and 3 above, I also think that generally the mechanics of the ship were not rugged enough for the high seas. The Germans didn't have much experience with these demands on machines because historically they thought of the Baltic, North Sea, coast protection and short voyages. Their other ships seem to have spent a lot of time in repairs and
Bismarck may have been the same. The ship was more vulnerable to a breakdown that could have the same consequences as decisive battle damage.
5) 2, 3 and 4 are magnified by the fact that the ship would essentially be alone on the high seas. It is one ship against the whole British Navy and Air Force assisted by the U.S. She is surrounded by hostile shores so no friendly port is available, while the enemy has many. The French and Norwegian ports were subject to air attack so it has to go around Britain for real safety in Germany.
These factors magnify the consequences of any decisive battle damage in terms of the rest of the voyage - the damage is permanent and makes it easier for the enemy to force battle again and on better terms. They also diminish the ship's greatest advantage because although it is difficult to sink it is easier to damage the ship enough to make it useless.