Bouncing bombs against Tirpitz

[paul.mercer]

Gentlemen,
I'm sorry if this question has been raised before, but do you think the bouncing bomb used against the dams would have worked against Tirpitz, surrounded as she was by anti torpedo nets. Personally I would have thought that the impact of a 5 ton bomb agaist her side would have caused enough damage without exploding, what are your views?

[ElBanditoVerde]

I believe that bouncing bombs called either highball or baseball were planned for this exact purpose. While I can't remember specifics I think the bombs used a 500lbs torpex warhead which I would imagine have been enough to break the tripitz's back

[Ersatz Yorck]

Skip bombing was used extensively in the Pacific against ships, and was successful in the battle of Bismarck Sea.

[tommy303]

There were two trials going on, Upkeep, which used a 4200kg bomb shaped like a depth charge and intended to be carried by Lancasters for use against the Ruhr dams. The other was Highball and was ultimately developed for use against Tirpitz and other ships. This bomb was smaller and two could be carried in tandem by Mosquito light bombers. However, problems with development and aiming the bombs delayed its readiness until late 1944, by which time its primary target, Tirpitz, had already been disposed of; consequently Highball never saw action.

[paul.mercer]

Thanks Tommy,
In your opinion would the Highball bombs been effective?

[tommy303]

Against a stationary target I am sure they would have been very damaging as each bomb carried 500-lbs of torpex. The effects would have been similar to a non-contact mine, although not detonating exactly under the ship's keel might have lessened the chances of breaking the ship's back. Once the Germans moved Tirpitz from Trondheim, to more northern anchorages, she was, I believe, out of range of the Mosquito aircraft which were to have been used.

[RF]

Gentlemen,
I'm sorry if this question has been raised before, but do you think the bouncing bomb used against the dams would have worked against Tirpitz, surrounded as she was by anti torpedo nets. Personally I would have thought that the impact of a 5 ton bomb agaist her side would have caused enough damage without exploding, what are your views?

As I understand it these bombs - called ''upkeep'' were actually mines which were detonated by a hydro-static pistol underwater at a set depth (in the case of the German dams) of 30 feet.

Therefore we are not talking about detonating these mines against the sides of Tirpitz on horizontal impact, but of the mines using backspin to go underneath the keel of Tirpitz and exploding directly underneath the ship.
I would imagine the impact would be very similar to the results of the mines laid by the midget subs that dropped their ''side-cargo'' onto the sea bed right under the Tirpitz' hull.
Assuming they correctly hit and richocheted from the side armour of Tirpitz.

I think it is unlikely that these ''upkeep'' would be used, as unlike a dam wall a ship isn't a fixed immobile target. Even at anchor its position can be varied, making it more difficult for aircrews to determine the absolutely correct angle of bomb run, particulary if there is heavy flak.

Note also that these mines did have thin casing (remember the problems Barnes Wallis had om the trials of these mines) - simply hitting the side of Tirpitz could cause the mine to disintegrate without even exploding while the backspin (if there is no disintegration) could carry an airborne mine away from the ship just as easily send it underwater.

[Vic Dale]

They were doing all sorts with bouncing bombs. Trials against the battleship Malaya showed that against side armour they would bounce back and away from the ship, but remain intact and on contact with the softer shell plate would enter the ship. I personally think from what I have observed in trials films, that they would have been effective. 4,000 pounds of RDX would have made quite an impact wherever they went off.

There is also some striking footage of bouncing bombs being dropped on a land range against a concrete target. Accuracy was good and the impact tremendous, but against an unarmed target accuracy would be good.

Barnes Wallace did not have trouble with the casings of the bombs, as is widely thought. In the Dam Busters film we are shown bits flying in all directions on contact with the sea, but the reality was that Wallace had packed wooden blocks around the bombs, sculpted to make the whole thing like a ball. It was the wooden blocks which were disintegrating and Wallace quickly realised during the first test drops that the shape was not critical to the result. A cylindrical bomb would bounce just as well as a ball. He had used golf balls in his initial tests and had concluded wrongly that the ball was the correct shape. He saw that after the wood had disintegrated the cylinder just kept bouncing.

The Germans on capturing a bomb more or less intact when one of the attacking Lancasters was brought down, began tests on their own version. Apparently they were able to interrogate one of the crew members as to the speed and direction of rotation. The German version was never a success at least I don't believe one was never used and it seems that despite a great deal of time and money being spent on this weapon that it was abandoned by the British in favour of better weapons.

The problem with attacking Tirpitz would lie in the ferocious hail of fire she could put up. The bomb run had to be straight and steady and at specified very low altitude of 60 feet and this could not be achieved under such fire. The lightly armed dams were a hard enough target, but a stationary Tirpitz with free arcs of fire in all directions would be a real hazard. The losses on the dams raids were extremely high, percentage wise and such losses could not be sustained by Bomber Command, without a serious loss of morale. Although the penalties for Loss of Moral Fiber were extreme, Harris did not want too many of his pilots cleaning toilets.