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No Swordfish shot down by Bismarck

Posted: Wed Nov 17, 2004 10:19 pm
by Javier L.
Could somebody explain why the Bismarck was unable to shoot down any of the attacking Swordfish torpedo planes? Was it because of a faulty antiaircraft battery? Bad weather? Limited visibility? Combination of all?

I did some research and noticed that the 10.5cm SK C/33 guns were installed in two different type of mounts. The four forward mounts were of the type L/31 while the other four aft were of the type L/37, and they were not "synchronized" by the same director. Maybe this is one of the reasons why no Swordfish was shot down, since many of them were hit by smaller 20 and 37 mm bullets and splinters. One Swordfish returned to the Ark Royal with 175 counted holes in wings and fuselage with both pilot and observer slightly wounded!

In the Tirpitz this deficiency was corrected and all eight 10.5cm double mounts were of the same L/37 type. It seems that it worked better than on Bismarck. On 9 March 1942, during the course of an air strike by 12 Albacore torpedo bombers (that were not the best aircraft in the world but surely better than the Swordfish), the Tirpitz avoided all torpedoes and her AA battery shot down two of the attacking planes. I think others were hit too.

Any thoughts?

"String Bags"

Posted: Wed Nov 17, 2004 11:50 pm
by George G.
There are many reasons given why Bismarck failed to shoot down any of the antiquated Swordfish-it seems, at least at first, to be somehow "unfair" that a modern, well-armed battleship could fail to shoot down obsolete biplanes that had to struggle to fly at 95 knots. In his memoirs, Mullenheim-Rechberg comments that it is very difficult to shoot down aircraft while a ship is constantly weaving to avoid bombs or torpedoes, and he cites an example of a british cruiser (HMS Ulysses) having exactly the same difficulty. For some reason, aircraft that head straight for you are difficult to shoot down (at least according to M-R).
Another reason often given, but which I am unqualified to verify, is that the Swordfishes' extremely slow speed might have worked to their advantage: Bismarck's flak was designed to track modern, fast aircraft and not the "string bags."
George G.

Posted: Thu Nov 18, 2004 12:15 am
by tommy303
There were some minor differences in the two models of 10,5cm mounts, but not enough to make any real difference in the shooting ability of the two types. Neither type was completely satifactory in regards to traverse and elevations speeds, particularly when the ship was manouvering rapidly while taking evasive action. This made it more difficult for the gunners to keep the guns on target long enough to do any good--remembering that an airplane attack is very fast compared to a surface target, and that the time of effective engagement is quite short. There was also a problem in the placement of Port and Starboard Nr 2 mounts in that their field of fire towards the after sectors was interrupted by the main cranes. In Tirpitz, the guns and cranes were repositioned so as to improve the field of fire.

The main problem was that the after port and starboard batteries were controlled primarily by the two after directors which in the case of Bismarck, were unstabilized, twin axis directors installed as a stopgap measure until the proper ones could be manufactured and fitted. The German government, in keeping to its obligations under the Soviet-German trade agreement, had provided the Russians with four of their most modern FlaK directors--the two after ones from Bismarck, and the two foreward ones from Prinz Eugen. Thus Bismarck and Prinz Eugen each went to sea with a pair of inferior directors which were not fully integrated into the FlaK fire control system. Prinz Eugen later received two fully stabilized triaxis directors to replace those sent to the USSR, while Tirpitz was completed with hers.


Posted: Fri Nov 19, 2004 12:43 am
by José M. Rico

The Germans were not happy at all with the with heavy 10.5 cm Flak configuration aboard the Bismarck. Here are some interesting excerpts translated in English by Ulrich Rudofsky from AVKS-700 (Artillerieversuchskommando für Schiffe), see pages 45-46:

"The fitting-out with two different types of mounts (twin mount C/31 and C/37), due to special conditions, has considerable operational disadvantages."

And later:

"…firing at sea targets or firing against low-flying aircraft with the 10.5 cm rapid loading C/33 in the C/37 twin mount is practically impossible by direct aiming of the guns with the available mechanical elevation alignment devices."

However, I wouldn't attribute Bismarck's failure to shoot down any airplanes exclusively to this fact. The bad weather conditions at the time of both air strikes is certainly a factor to consider too.


Posted: Fri Nov 19, 2004 1:16 am
by Tiornu
One thing we should keep in mind--it's not easy to shoot down an airplane. Even on a typical day, it takes mulitple thousands of rounds to account for one kill, on average.

Re: "String Bags"

Posted: Fri Nov 19, 2004 6:42 am
by Javier L.
George G. wrote: For some reason, aircraft that head straight for you are difficult to shoot down (at least according to M-R).
Another reason often given, but which I am unqualified to verify, is that the Swordfishes' extremely slow speed might have worked to their advantage: Bismarck's flak was designed to track modern, fast aircraft and not the "string bags."
I have heard this theory many times too, but I still don't understand how a slow moving aircraft can have any advantage at all. If I were a gunner I would prefer attacking planes to go as slow as possible no matter how modern my weapons are.

Moreover, I don't see how an aircraft that heads straight towards you is more difficult to shoot down than one that approaches your ship from a different angle. :think: Actually I think it would be easier to hit since you don't have to worry about the x-axis and the more it closes the bigger the target is.

Posted: Fri Nov 19, 2004 2:52 pm
by Ulrich Rudofsky
The problems with the Flak are that it did not pass the complete testing and mandatory approval by the gunnery inspection command (AVKS). The full report AVKS 700/41 is on this site. For example the Flak was designed for fast flying and floating objects with hard skins, and according to the report: "It was also noted that the He 111 aircraft, used for Flak target display, could only remain aloft for approximately 1 ½ hours; this is absolutely incomprehensible considering the purported action radius of this type of aircraft. In the future, these complications will require the readiness of two aircraft that can relieve each other during Flak firing tests of longer duration.
The available Stuka targets do not represent reality either, since they drop and dive much too slowly.
The firing on towed floating targets was not accomplished due to the lack of time and prevailing weather conditions." The inspection of the Flak was ccut short in protest of the AVKS, they were incomplete, large portions were cancelled, i.e, the Flak crew did not receive proper training training such as the 38 cm crews did, though even their training, according to the AVKS, was not adequate due to instrumentation still uninstalled and poor targets construction etc.

Re: "String Bags"

Posted: Fri Nov 19, 2004 3:48 pm
by Tiornu
It's incomprehensible to me that the Germans would not have weaponry capable of tracking slow aircraft. The standard French carrier torpedo plane during the time when Bismarck was under construction had a lower top speed than the Swordfish. I know the Germans weren't giving much thought to their own torpedo planes, but they couldn't possibly ignore both Britain's and France's primary battleship-killing planes...right?

Posted: Fri Nov 19, 2004 5:12 pm
by Ulrich Rudofsky
It is pretty clear that Lindemann worried about the Flak problems and wrestled with them. Even in port Bismarck scored no significant hits on high altitude bombers under 'live' condition; however, this is not a fair statement, since Bismarck was limited by keeping a low profile during bombing raids in Hamburg and Kiel. Here is Lindemann's proposal to the EKK Erprobungskommando für Kriegsschiffneubauten - Testing Command for New Ship Construction as early as 31 October 1940.

DRAFT Translation : Ulrich Rudofsky

Attachment to Testing Command for New Ship Construction Report No. Secret 5318/1940

At Sea, 31 October 1940

Testing Group “Bismarck”
Report No. Secret 120 Ordnance Officer [Wa. O. = Waffen Offizier?]

For information only:
The Command Battleship “Bismarck”, [present] post office location.

Subject: Relocation of 3.7 cm twin Flak and 2 cm Flak [L] 30.
For Action by: Testing Command for New Ship Construction test [group “Bismarck”].

1. The 3rd and 4th 3.7 cm of the upper “Mastdeck” [USN 04 Deck, RN Signal Deck] are improperly positioned, and they have a relatively small sweep angle in lateral their bearing as well as in elevation. This is principally caused by the forward rangefinder rotary dome, and from above by the protruding equipment of the mast, yardarms, and antennae, and laterally and abaft by the night recognition signal lanterns and signal halyards attached to forward signal spreaders, as well as by the forward Flak fire control station and the foremast rangefinder stations.

In order to achieve larger sweep angles and, therefore, more effective utilization of these weapons, they must be assigned a location that is farther forward and laterally farther outboard. This can only be accomplished by the relocation of the weapons from the upper 04 deck to the lower 03 deck [RN No. 2 platform deck] at the location where presently both of the bearing compasses were mounted. These bearing compasses, according to the ship’s command, are not necessary and can be dismounted and removed from shipboard. The deck must be modified on both sides for mounting of the guns by construction of 0.4 m high pedestals with an appropriate diameter of operating radius, and they must be built out in a swallow-nest-like shape like that of the bridge deck that lies below it. The operating radius is not to be fully extended outward, because deployment of the guns toward the lee side will not be required. The support cylinders [columns?] are to be attached to the deck structures. The relocation of the two bulkhead [compartment] doors of the bridge deck, as well as the life raft lockers on the 03 deck will be required.

2. The 3rd and 4th 2 cm Flak [L] 30 that are presently located on the lower mast deck [Unteres Mastdeck = 03 deck] must also be relocated, and, namely, to the space that was freed-up on the upper mast deck [Oberes Mastdeck = 04 deck] by the removal of the 3.7 cm. In order to achieve the largest possible elevation angle also for these weapons, they should be placed as far forward as possible along the railing, taking into consideration their operating radius. Furthermore, the “Jesson” signal horns [fog and navigation?] and the racks [retainers, brackets] for the NES [? Perhaps: Nebel-Erzeuger-System = Fog or smoke generating system?] must be moved far enough aft so that they are clear of the line of fire.

3. The 1st and 2nd 2 cm Flak 30 are in position on the forecastle and are severely exposed at sea to wind and boarding seas. Their manning is only permissible on a calm [becalmed, moored] ship. It is, therefore, necessary that the 3rd and 4th 2 cm Flak 30 that are to be relocated to the upper mast deck [04 deck], be replaced as soon as possible with twin mounts, in order to also secure complete forward Flak protection [when underway] at sea.

4. The 11th and 12th 2 cm Flak 30 that are mounted on the upper deck level of the leading edge of turret “D” can be folded down [can be stowed]. They have a restricted sweep angle here, and they can only be engaged when the aft 38 cm turrets are not firing, i.e., when they are in their lash-down [resting, frapped] position.

In order that both these [Flak] weapons can be deployed to full advantage, the required base mounting plates for both sea and port emplacement must be installed. For the mountings while in port, the locations on the quarterdeck [poop] on both sides of the descending gangway at frame 19 have been chosen.

The base mounting plates for the emplacement at sea are to be installed on deck behind the aft night director stand [night fire control station].

In order to obtain the required radius for operation of the weapons, the deck must be sufficiently lengthened towards the stern. Later, the command “Bismarck” will request that these stands be equipped with quadruple mounts.

The placement of the defensive incendiary bomb launchers [literally: enemy fire bomb throwers], which were also planned for this space, can be installed somewhat more forward on both sides of the aft stand.

These proposed layout options offer the best possible exploitation [utilization] of these weapons at sea as well as in port.

5. Therefore, it is requested that permission for the execution of the proposals 1., 2., 3., and 4. be procured immediately in order that the relocation of the weapons can still be accomplished while the finishing work is being completed.

[Signed: Lindemann]

no swordfish shot down by bismarck

Posted: Sat Nov 20, 2004 5:21 pm
by dgrubb64
The problem of shooting down anything is trying to predict the distance infront that you have to aim which will depend on the distance away of the target, the speed of the target and your movement.

If a plane was coming straight at you to launch a torpedo and you were not moving then torpedo would hit exactly underneath you. If a plane were coming straight at you to launch a torpedo and your ship was moving then the torpedo would hit some distance behind you or miss.

the plane would have to aim at the point where they though the target would be x amount of time after torpedo launch (x being the travel time of the torpedo), therefore a plane would not be coming straight at you. when aiming the guns you would need therefore to aim so far in front (the distance would depend on the speed of the aircraft and the velocity of the shell being fired) this aiming in front applies to aircraft coming straight at you if they are slightly higher or lower than the platform from which the guns are being fired.

If the guns were using a basic mechanical computer to calculate the distance that they would have to aim off was it able to calculate speeds as slow as those that the swordfish were flying at.

Taking into consideration the above and the following points:
The bismarck was moving forward
The bismarck was swerving to miss the torpedoes
The Bismarck was rolling
The crew of the bismarck had been at action stations for a long period and therefore tired

I can understand how difficult it would be to hit even the swordfish never mind more modern faster aircraft.

If you consider how during the Pacific campaign the americans in particular added massive amount of anti-aircraft guns to their battleships you can see how their chances would be increased (I think the Iowa had 137 20-40 mm cannon added during her construction to counter the aircraft threat). :!:

Posted: Mon Nov 22, 2004 3:27 am
by tommy303
The sFlaK fire control system did indeed use a mechanical, analog resolver to work out the basic fire control solution so that the shell would rendezvous with the target, and a predictor which provided continual data for the resolver and fuze setting machines. Even with such a slow aircraft as the Swordfish, the effective engagement time is very short. particularly considering the at times poor visibility underwhich the firing took place. I would think probably the range at opening fire was not more than 10 000m with the heavy FlaK. Nominally, two mounts would be directed against a specific target in an approaching flight and kept under director control.

From that range, a Swordfish would reach its minimum drop distance of 1000m or so in about 4 minutes. Allowing for perhaps a minute to aquire target and the fact that the heavy FlaK was ineffective much below about 3000m due to it not having sufficiently fast train and elevation speeds, the effective engagement time is reduced to two minutes or a little less. Any major manouver by the ship would most likely throw the heavy FlaK off target completely, and reaquisition of the target would be most unlikely. At best the heavy FlaK battery in question would be redirected to a new target.


Posted: Wed Nov 24, 2004 1:55 pm
by Larue
has anybody considered that the German gunners were maybe just bad shots? how much anti aircraft practice had they undergone?

occam's razor.

shooting and hitting a moving target is difficult, even when the shooter is stationary. when both shooter and target are moving in 4 planes, lack of hits is not suprising. recall if you will, the actual footage of kamikaze attacks on the American fleets, you can clearly see the amount of aaa fire in the air, and that was just the 1/5 tracer from multiple ships. how many aircraft were shot down? relatively few.

it's no mystery to me

best regards

larue 8)


Posted: Sat Oct 22, 2005 1:43 am
by dunmunro
I think you will discover that most of the swordfish attacks were launched in deep twilight or even nautical darkness. Roskill states that the 1st attack commenced at midnight on the 25th of may. The 2nd, crippling attack commenced at 20:47 on the 26th of may. No swordfish were shot down because the gunners were probably blinded by by the flash of thier guns and/or because it was simply too dark to locate the aircraft.

The swordfish might appear to be obsolete in may 1941 but this is not really the case. In fact, it was an all weather, day/night, radar equipped, strike bomber with search and strike capabilities posessed by no other navy. In April 1942, Admiral Somerville planned to attack the IJN carriers at night with his radar equipped Albacores. So even though the RN appeared hopelessly outmatched in the Indian Ocean, they actually had a "secret weapon" which might have evened the odds.



Posted: Tue Feb 05, 2008 4:33 am
by hellomartin
My dad flew Swordfish during WWII (but not against Bismarck). I remember him telling me that German gunners had been trained to fire some distance ahead of attacking aircraft and Swordfish pilots believed that their slow speed was indeed an advantage.

Also, reading an account of the attack in the excellent recent book "Ark Royal" by Mike Rossiter, it seems the gunners of Bismarck put up a creditable performance. The Swordfish pilots report that the flight deck of Ark Royal was sea-sawing by 16 metres when they took off, so presumably Bismarck's gunners were dealing with the same sort of conditions.

Here is a quote from the book of the pilots' experience of the anti-aircraft fire.

"On breaking through the low cloud they discovered the Bismarck was four miles away. The ship immediately opened fire and the barrage was intense. It began five seconds after they had emerged from the cloud and started their dive. Large bursts came up very close, including one very near miss under his plane, and the pilot has the strong impression that each gun mounting had its own radar control. He described the ack-ack as reddish-coloured tracer going past at about one shell a second. Another pilot thought it was like flying into hail. In the open cockpit of the Swordfish the noise and blast of the exploding shells could be felt by the pilots and observers. The smell of cordite was strong. At one point two shells burst together 30 metres to starboard and below, the blast of which battered the plane and turned it off its course.

"After diving below 1,000 feet the heavy shell fire seemed to abate. A series of double flashes were seen from amidships but the rate of fire appeared to be slower and the flashes were vivid orange with little smoke. The pilot dived as low as he could and when he was 2,000 metres from the target the rapid-firing guns started up, orange tracer coming at him in a straight line. Another pilot reported that the gun flashes from the ship appeared vivid yellow tinged with green, with cordite smoke brownish and small in quantity. Then, as the planes got closer, smaller red tracer appeared. Lt Beale, an experienced veteran of many of Ark's operations, said that the fire was more intense than anything he had experienced."

The Swordfish attacked from many different directions simultaneously, so the gunners could not concentrate their fire. "Remarkably, only one Swordfish was seriously damaged during the attack, both the gunner and telegraphist sustaining wounds. The aircraft was hit 175 times, and one of its struts supporting the upper and lower wings was severed. Nevertheless the pilot, Sub Lt Swanton, managed to fly it back to the Ark Royal and make a successful landing."

The account of the attack then shifts to onboard Bismarck. "The men in the control platforms in the engine room had to keep their wits about them. 'All ahead full! 'All stop!' 'All back full' were the ever changing orders with which Lindermann sought to escape the torpedoes. We had been under attack for at perhaps 15 minutes when I heard the sickening sound. Two torpedoes exploded in quick succession, but somewhere forward of where I was. Good fortune in misfortune, I thought....The attack must have been almost over when it came, an explosion aft. My heart sank. I glanced at the rudder indicator. It showed 'left 12 degrees'. It did not change."

Posted: Tue Feb 05, 2008 1:34 pm
by RF
For the record I think it should be remembered that while none of the Swordfish were lost it certainly wasn't the case that they were not hit by German fire, as noted in the post immediately above this one.