1944: Flak Alone Blasts the Allies out of the Sky

[Lars]

In 1944 the average amount of rounds used to down a bomber
(4 engines) was :
16000 8,8cm (flak 36/37)
8500 8,8cm (flak 41)
6000 10,5 cm
3000 12,8cm

This was an improvement over the early war years due to better use of radar, grooved projectiles, the fragments of the shells grew from 1-7 gr. to 80-100 gr. pieces and other improvements.

However, there was still room for better effectivenes: The double fuzes (contact and timed) introduced in late 1944 increased effectiveness by:
8,8 cm guns 5 times.
10,5 cm guns 3 times
12,8 cm guns 2 times.

If the Germans had developed proximity fuzes (like the Americans were already using in the Pacific) they could have increased their flak efficiency by another factor of 3-4.

Consider this what-if: The Luftwaffe lost the air war over the Reich in early 1944. But what if the double fuzes and the proximity fuzes were ready by then? The effectiveness would then go up by:

8,8 cm guns 15-20 times
10,5 cm guns 9-12 times
12,8 cm guns 6-8 times

Bottom line: Flak alone blasts the RAF and the USAAF out of the skies.

Thoughts, anyone?

[Andy H]

Wouldn't effect B29's which if your WI scenario were coming true, would be speeded up and used in Europe rather than just Japan

Andy H

[Tony Williams]

The RAF would probably have switched to very low-level attacks (especially with Mosquitos) which the big guns would have found very difficult to deal with. So the Germans would have responded with more light flak around targets. So the RAF would have responded by sending in Mosquito fighter-bombers to take out the light flak before the bombers arrived, and so on...

Tony Williams: Military gun and ammunition website and Discussion forum

[Lars]

Wouldn't effect B29's which if your WI scenario were coming true, would be speeded up and used in Europe rather than just Japan

Andy H

Probably yes. However, the 88 mm/41 had an effective top ceiling of 10.5 km (shell speed at 1km/sec). Dunno if B-29 attacks were carried out above 10.5 km (though the B-29s top ceiling was - what - 12 km?). If not, the B-29 would have severe problems as well.

[Lars]

The RAF would probably have switched to very low-level attacks (especially with Mosquitos) which the big guns would have found very difficult to deal with. So the Germans would have responded with more light flak around targets. So the RAF would have responded by sending in Mosquito fighter-bombers to take out the light flak before the bombers arrived, and so on...

The Mosquito was the lost chance of the RAF. A fleet of Mosquitos instead of Lancasters would have meant several "Hamburgs" instead of only one. Still, making the entire RAF and USAAF four engine bomber fleet obsolete simply by improving the fuzes of the flak shells would be a heavy blow to the Allies. Besides, switching to Mosquitos would take time AND persuasion of Bomber Harris.

[maltesefalcon]

The RAF would probably have switched to very low-level attacks (especially with Mosquitos) which the big guns would have found very difficult to deal with. So the Germans would have responded with more light flak around targets. So the RAF would have responded by sending in Mosquito fighter-bombers to take out the light flak before the bombers arrived, and so on...

The Mosquito was the lost chance of the RAF. A fleet of Mosquitos instead of Lancasters would have meant several "Hamburgs" instead of only one. Still, making the entire RAF and USAAF four engine bomber fleet obsolete simply by improving the fuzes of the flak shells would be a heavy blow to the Allies. Besides, switching to Mosquitos would take time AND persuasion of Bomber Harris.

Mosquito's effectiveness was partly due to its elite status. The best navigators and selected pilots were used, as they were often required for Pathfinder missions. Expanding their role to the entire Bomber Command would be like trying to build an entire army group of snipers. The overall result would be diluted by the expansion.

Also the Lanc could carry nearly 5 times the bomb load to the same range.

I will have to check, but perhaps their wooden construction was difficult to mass produce in greater quantity? Can anyone provide better data on this?

[Zimmerman]

Wouldn't effect B29's which if your WI scenario were coming true, would be speeded up and used in Europe rather than just Japan

Andy H

Probably yes. However, the 88 mm/41 had an effective top ceiling of 10.5 km (shell speed at 1km/sec). Dunno if B-29 attacks were carried out above 10.5 km (though the B-29s top ceiling was - what - 12 km?). If not, the B-29 would have severe problems as well.

IIRC, LeMay had his B-29s in the Pacific go in low at night due to inaccuracy from high altitudes. Perhaps something similar would happen in Europe with the '17s and the '24s

-David

[Von Schadewald]

Too late, the Germans discovered that dispensing with time-fusing and firing at the bomber directly, with the intent of a direct hit , rather than a burst barrage, was much more effective, with a much higer rof. This discovery in the last months of the war, resulted in a sudden spike in bommber losses, but too late. If they had employed time-fuseless direct fire in 1943, even without proximity fuses, Allied losses might have become a schtickel vicious.

[Tony Williams]

Mosquito's effectiveness was partly due to its elite status. The best navigators and selected pilots were used, as they were often required for Pathfinder missions. Expanding their role to the entire Bomber Command would be like trying to build an entire army group of snipers. The overall result would be diluted by the expansion.

Also the Lanc could carry nearly 5 times the bomb load to the same range.

I will have to check, but perhaps their wooden construction was difficult to mass produce in greater quantity? Can anyone provide better data on this?

The Lanc could indeed carry a much heavier bombload, which was useful in carrying the super-heavy bombs. However, the RAF themselves did an analysis during the war to compare the Lanc with the Mosquito, which went something like this:

- Typical bombload - advantage Lanc
- Number of sorties before being shot down - big advantage Mossie
- Total bombload carried before being shot down - advantage Mossie
- Cost of each plane - advantage Mossie
- Cost of delivering each ton of bombs in the life of the plane - big advantage Mossie

And that's without taking into account the cost of the crews, which were four times bigger in the Lanc, plus the retraining cost because Lanc crews were lost ten times as often.

Not surprisingly, this study concluded that the Mossie was a vastly more efficient bomber than the Lanc.

However, you are right that the manufacturing technology was very different and it would not have been easy or simple to switch from Lancaster to Mosquito production (let alone convincing Harris!).

Tony Williams: Military gun and ammunition website and discussion
forum

[Tony Williams]

Too late, the Germans discovered that dispensing with time-fusing and firing at the bomber directly, with the intent of a direct hit , rather than a burst barrage, was much more effective, with a much higer rof. This discovery in the last months of the war, resulted in a sudden spike in bommber losses, but too late. If they had employed time-fuseless direct fire in 1943, even without proximity fuses, Allied losses might have become a schtickel vicious.

Yes, I took that to its logical conclusion in 'The Foresight War'. If you're relying on contact fuzes for direct hits the shells don't need to be as big. So fire sub-calibre shells at a high velocity to improve their altitude performance. And as an extra touch, replace the morale effect of flak bursts with a very big tracer on the shells, so the bomber crews can see them streaking up towards them - should put any bomb-aimer off!

TW

[Lars]

And as an extra touch, replace the morale effect of flak bursts with a very big tracer on the shells, so the bomber crews can see them streaking up towards them - should put any bomb-aimer off!

What a tremendous idea!

[Lars]

Great to see the number of reactions! This corresponds with my own gut-feeling that better German flak is an underdiscussed what-if, as opposed to the ME 262, XXI U-boat, etc.

IIRC, LeMay had his B-29s in the Pacific go in low at night due to inaccuracy from high altitudes. Perhaps something similar would happen in Europe with the '17s and the '24s

At high altitudes the precision drops off quickly. I don´t know the Norden bombsight figures but they were probably similar to the German Lotfe-7D tachometric sight which gave a CEP of around 90m from 3,000m altitude and 400m at 6,000m. And those numbers assumed ideal conditions without anyone shooting at you.

Bottom line: B-29s carrying out precision target bombing from 10.5 kms high was simply not effective.

But would the B-29 be able to hide up there at all out of flak range? The service ceiling of the B-29 was 36,000 feet (10,973 m.), only 1,000 feet (100 m.) higher than the B-17. The effective ceiling of the 88 mm Flak 41 was 10,675 meters, only 300 meters lower than the sevice ceiling of the B-29. Basically the margin for the B-29 would be the last 300 meters of its service ceiling and I really doubt if coordinated attacks could be carried out from that close to the service ceiling, and, if they could, the Americans should count themselves lucky if anything was hit at all.

[Von Schadewald]

The effect of tracer on attacking planes could be tremendous. At the time of her loss, Prince of Wales had just one Bofors that was firing tracer, & the Japanese pilots afterwards reported that it really threw them.

Imagine if the British had fitted their 8-barrelled pom poms to fire tracer! The sight of a hail of coloured glowing globules in broad Pacific daylight seemingly coming straight at you would have been unnerving to say the least, especially in the pre-Kamikaze era.

[Andy H]

The effect of tracer on attacking planes could be tremendous. At the time of her loss, Prince of Wales had just one Bofors that was firing tracer, & the Japanese pilots afterwards reported that it really threw them.

Imagine if the British had fitted their 8-barrelled pom poms to fire tracer! The sight of a hail of coloured glowing globules in broad Pacific daylight seemingly coming straight at you would have been unnerving to say the least, especially in the pre-Kamikaze era.

Lets keep this thread on track. Just a note that Tracer bullets were one of the main causes of blockages with early RN AA Guns.

Andy H

[Lars]

Too late, the Germans discovered that dispensing with time-fusing and firing at the bomber directly, with the intent of a direct hit , rather than a burst barrage, was much more effective, with a much higer rof. This discovery in the last months of the war, resulted in a sudden spike in bommber losses, but too late. If they had employed time-fuseless direct fire in 1943, even without proximity fuses, Allied losses might have become a schtickel vicious.

All the more remarkable since German shells were filled with up to 1/3 salt during the last months of the war due to lack of explosives.

Von Schadewald and others,

What was the effectiveness of direct fire without time-fuzes: 2 times more effective, 3 times ..?