Luftwaffe after BoB: strategy, tactics, tecnology?

[davebender]

Historical Production of 12.8cm flak.
Production Stats on German Tube-fired Weapons 1939-1945
65 during 1942
298 during 1943
664 during 1944
98 during 1945.

12.8cm was by far the most effect Luftwaffe flak gun vs high altitude heavy bombers due to shell flight time which was 1/3rd that of 8.8cm flak. Historical Luftwaffe didn't get serous about production until 1944 and even then it was about 1/3rd of Luftwaffe 8.8cm flak production. Let's begin Luftwaffe 12.8cm flak production during 1941 with target of 50% of 8.8cm Luftwaffe flak.

Projected Production of 12.8cm flak.
936 during 1941
1,438 during 1942.
2,208 during 1943.
966 during 1944.
.....4,582 12.8cm flak guns guarding German industry against high altitude bombers by January 1944. 4,215 more then historical (i.e. 11 times historical quantity).

 

[Aozora]

Historical Production of 12.8cm flak.
Production Stats on German Tube-fired Weapons 1939-1945
65 during 1942
298 during 1943
664 during 1944
98 during 1945.

12.8cm was by far the most effect Luftwaffe flak gun vs high altitude heavy bombers due to shell flight time which was 1/3rd that of 8.8cm flak. Historical Luftwaffe didn't get serous about production until 1944 and even then it was about 1/3rd of Luftwaffe 8.8cm flak production. Let's begin Luftwaffe 12.8cm flak production during 1941 with target of 50% of 8.8cm Luftwaffe flak.

Projected Production of 12.8cm flak.
936 during 1941
1,438 during 1942.
2,208 during 1943.
966 during 1944.
.....4,582 12.8cm flak guns guarding German industry against high altitude bombers by January 1944. 4,215 more then historical (i.e. 11 times historical quantity).

And where are the extra personnel to man (or woman) all of the additional flak guns going to come from? As it was, by mid-1943 the Germans were starting to reach the bottom of the barrel when it came to recruiting able-bodied people for the Flak units - an extra 4,215 flak guns would have presented more than a challenge; chances are a great deal of that extra production would have been wasted.

If anything, the Luftwaffe should have relinquished control of the Flak units in favour of the Whermacht, except, perhaps for units defending Luftwaffe positions. Incorporating control of all Flak into the Luftwaffe was far too wasteful of resources and manpower.

 

[wiking85]

Ah, totally forgot about the FLAK buff:
Axis History Forum ? 1944: Flak Alone Blasts the Allies out of the Sky
Basically the most effective FLAK shell from late in the war was a double fuze shell that used a tracer component to detonate the shell if it didn't hit anything, but also a contact fuze when they hit what they were aiming at. It was much cheaper than the timed fuzes used for box barrages, didn't require timing settings so was resulted in a much higher rate of fire and a resulting increase of bomber hits, and of course took advantage of the concept of base bleed to increase shell speed and therefore accuracy, while also resulting in a significant altitude increase due to less drag. Implement that shell in 1940 and you got more bombers shot down and a lot cheaper shells:
https://en.wikipedia.org/wiki/Base_bleed
It basically gives the standard 88mm the performance of the 128mm.

 

[tomo pauk]

In case the flak shell did not hit anything, but traveled a bit instead and then self-destructed, the shrapnels would've streaked way above the bomber stream. Even when using such fusing, the Flak arm was been able to kill less than 10 USAF planes per day in 1944; that is for maybe 7-8000 heavy Flak pieces and thousands of light Flak that were used west of Poland. Many more A/C were damaged, of course.
Luckily, Germany did not have proximity fuses in timely manner.

 

[Aozora]

Put 1944 Bf109s into service earlier; More/sooner /AS, GM1, MW50

With the DB 605A, 1.42 ata was not fully available until late 1943 - some 18 months after its operational debut in June 1942. Daimler-Benz should have been forced to concentrate on ironing out all problems with the 605, and much more quickly; that would have been the only way the more powerful AM/AS series might have been made available before mid-1944. As it was, the numbers of obsolescent DB 650A powered 109s being built well outnumbered the AM/AS 109s (about 5 to 1) right through to the end of 1944. To build more AM/AS would have required a major effort on D-B's part.

Somehow, get several bombers over the UK to hit the bomber bases, mid '43 on. Many benefits here. Does not have to be many planes but it has to be threat to cause nightly patrols, fear, disrupted sleep as crews would have to go to bunkers. Long range Fw190G with wing tanks and centerline cluster bomb mix of super frag to puncture fuel tanks and incendiary to ignite the spills. Maybe the LW had a operation or two like this, somebody help me here.

The Luftwaffe ditched nightfighter intruder operations in 1941 because Hitler and Göring didn't believe they were making much of an impact. They were wrong; had the Luftwaffe restarted its intruder operations in 1943 it would have caused major problems for the RAF. A few Luftwaffe nightfighters infiltrating the returning bombers over bomber bases would have been very difficult to counter, because the RAF's nightfighters would have been confronted with large numbers of radar returns. Ditto the ground defences.

 

[Shortround6]

The British were using IFF by the end of 1940. Now IFF is/was nowhere near 100% reliable but it sure cuts down on the number of "bogies" the defending fighters have to investigate. Unless the Germans get real good at spoofing the IFF. The Night fighters would be directed at any 'blips' not showing as 'friendly' to get a visual to see if it was a German or a returning British bomber with a malfunctioning IFF unit (no blind firing).

Even the airborne radar was often fitted with IFF features to check out intended targets.

 

[kettbo]

orchestration of staging and jockeying 54 planes per bomber field is major undertaking. Throwing airstrikes at them during the night and wee morning hours would pay huge dividends. With the HE and incendiaries, might as well have some delayed action fuses to delay clean-up and to throw off time tables.

Naturally you'd need a coordinated plan to get the strikers through; diversions, deception, jamming...hmmmm cannot recall the LW using CHAFF but what's good for the goose is good for the gander

Let me think what could be best used for this;
needs the range to get to the bomber bases and back plus diversions
needs to fly fast....low altitude penetration I'm thinking
navigator/second set of eyes
internal bomb bay a plus for speed and range....thinking Me410

WIKI says KG 51 elements flying Me410s between late DEC 43 and May 44 were decimated. Not sure of the tactics here.

 

[Aozora]

The British were using IFF by the end of 1940. Now IFF is/was nowhere near 100% reliable but it sure cuts down on the number of "bogies" the defending fighters have to investigate. Unless the Germans get real good at spoofing the IFF. The Night fighters would be directed at any 'blips' not showing as 'friendly' to get a visual to see if it was a German or a returning British bomber with a malfunctioning IFF unit (no blind firing).

Even the airborne radar was often fitted with IFF features to check out intended targets.

With hundreds of bombers returning over a relatively concentrated area, trying to locate a few Luftwaffe fighters in amongst them would have taken quite a while; even with IFF, it would have been like trying to pick a sultana from a raisin in a fruitcake full of raisins, particularly if the sultana sticks relatively close to some raisins; ie: it would have been time wasted when time was critical.(Not forgetting, too, the Germans had IFF and a very sophisticated radar system - nevertheless, British night intruders were able to penetrate the defenses.)

http://stelly.com.au/8363-41349-thickbox/sultana-hot-cross-buns-top-mint.jpg

In addition, the German night fighter crews would have had the advantage of knowing that any aircraft that appeared on their radar would have more than likely been British. Another factor was that bomber crews returning from a mission were usually exhausted and their vigilance poor, making them easier targets than when over enemy territory. Even a few night intruders ranging around bomber bases while aircraft were attempting to land would have wreaked havoc.

 

[stona]

People always seem to forget that an enemy will react to any change in the other sides tactics.
Had the Luftwaffe developed intruder operations against the RAF bomber airfields and/or returning bombers, as opposed to attempting to use it's limited night fighter force to defend its own air space then there were various things the RAF might have tried. Mounting more and different operations against the Luftwaffe's own fields for a start. It would certainly use more of its own night fighters to protect the returning streams and Bomber Command's airfields. The RAF was also blessed with the best night fighter of the war and if required Mosquito production could have been adjusted to produce more.
Any such Luftwaffe campaign might have proved more expensive than the Luftwaffe could afford, particularly in highly qualified and almost irreplaceable night fighter crews.

The British had a lead in electronic measures which was never lost during the war. Several German systems were based on inferior copies of British technology. The British also had an enormous manufacturing capability across the Atlantic. Late in the war Germany struggled to produce systems in any kind of meaningful numbers.

Cheers

Steve

 

[tomo pauk]

It would take time to introduce the Mosquito.
By then, LW can use the Ju-88, armed with only internal bombs (50 kg/110 lbs), to shower the airfields with those. Any radar detection and interception vs. a low lying aircraft will be a tough job for a defender, and Beaufighter and Defiant will have as good as no performance edge over a clean Ju-88 (no racks, maybe even with gondola deleted).

Hopefully, Erich can stop here and add to the discussion?

 

[stona]

The Luftwaffe was no better at bombing small targets at night than the RAF was. It could hit a city particularly if guided there electronically, but an airfield, even if it could find it?
Cheers
Steve

 

[Aozora]

People always seem to forget that an enemy will react to any change in the other sides tactics.
Had the Luftwaffe developed intruder operations against the RAF bomber airfields and/or returning bombers, as opposed to attempting to use it's limited night fighter force to defend its own air space then there were various things the RAF might have tried. Mounting more and different operations against the Luftwaffe's own fields for a start. It would certainly use more of its own night fighters to protect the returning streams and Bomber Command's airfields. The RAF was also blessed with the best night fighter of the war and if required Mosquito production could have been adjusted to produce more.
Any such Luftwaffe campaign might have proved more expensive than the Luftwaffe could afford, particularly in highly qualified and almost irreplaceable night fighter crews.

The British had a lead in electronic measures which was never lost during the war. Several German systems were based on inferior copies of British technology. The British also had an enormous manufacturing capability across the Atlantic. Late in the war Germany struggled to produce systems in any kind of meaningful numbers.

Cheers

Steve

By the time new tactics are devised a lot of damage can be done, and there's no guarantee that the new tactics would necessarily work (case in point, the advent of the Fw 190 vs the Spitfire V - how many Spitfire Vs were actually saved by cruising at high speed over enemy territory?).

Of course, the enemy will react, but there's no point in refusing to start - or stopping - an effective strategy for fear that the enemy will eventually find some means of countering it. The RAF had a lot more to lose, had the Germans let loose an effective intruder campaign against the heavy bombers, than the Luftwaffe had to lose between 1941 and 1944.

As it was, even with their advanced equipment - including the Mosquito - the RAF night fighters didn't have it all their own way, as witness C. F Rawnsley's (John Cunninham's R/O) account of late 1943 from Night Fighter;

An effective intruder campaign would not have been a war winner, but it could potentially have done a lot of damage to the RAF's heavy bombing campaign and, possibly, to the bomber crews' morale.

The Luftwaffe was no better at bombing small targets at night than the RAF was. It could hit a city particularly if guided there electronically, but an airfield, even if it could find it?
Cheers
Steve

There would have been lots of aerial targets for Luftwaffe intruder crews to choose from, plus the RAF's bomber airfields were usually lit up like Christmas trees, thus easy to find. With intruders around all those airfield lights would have had to be switched off. Imagine the effects of that with lots of low on fuel, or damaged, heavy bombers trying to land? Still a win-win, even if the bombs themselves didn't do a lot of damage.

 

[tomo pauk]

About the weaponry: what to develop further?
The MG 151 is in the works, with MG 151/20 following shortly. The MG 131 is also in the development. Maybe go for a 'mid-power' 30mm, instead of the 'low-power' MK 108? Ie. something around 650-700 m/s muzzle velocity, with muzzle brake (so the weight can be within suitable limits; muzzle brake might not be necessary for the prop-firing installation), 500-600 rpm. Here might an V-12 engine come in handy for the Fw-190 - a powerful cannon in the centreline, and either two similar cannons outboard (in case they use the 'open bolt' firing) of the prop disc, or two cannons inboard (if the design is of 'closed bolt' firing) the prop disc. Until the production is in high gear, the 20mm can be installed instead of wing-mounted 30 mm, trajectories would be similar, unlike what was the case for the MK 108.
As a further design for aerial targets, perhaps neck-out the MK-101/103, to fire a 600-700 grams shell at ~650 m/s? One weapon for the V-12 powered Fw-190, plus either 20mm or 30 mm in the wings.

 

[Shortround6]

It is not even a question of open bolt or closed bolt. The bigger cartridge cases (with their much larger powder charges) suffered from inconsistent timing from firing pin strike to round exiting the muzzle. Electric ignition helped a bit but the big cases were never adapted to a synchronized system. Result of a failure is also rather severe. A 12.7-13mm machine round hitting the prop may give you some problems. Depending on the prop even a 20mm round might not take the plane down (at least in catastrophic fashion). A 30mm projectile hitting/exploding in contact with the prop? Heck, even the prop just colliding with a 330gr projectile could cause some major problems.

BTW a 10% increase in velocity often needs 20% more propellant so a 20% increase is going to need over 40% more. Throw out everything and start over?

For a gun that is used to best effect only on a V-12 powered Fw 190 airframe?

Germans had enough trouble with different guns and ammo as it was. FW units got electric primed 20mm ammo and 109 units got percussion (one reason for not mounting a single 20mm gun in a pod under the fuselage of the 109).

German Luftwaffe had 7.9mm, 13mm, 15mm, at least FOUR kinds of 20mm and at least 2 types of 30mm ammo in service in large numbers, not including experimental stuff. Fascinating to read about but a supply officers nightmare. Lets throw in the different types of projectiles for each ammunition type.
Lets also remember that the the Army used some different 20mm ammo.
Perhaps only the Japanese had such a complicated supply situation.

 

[tomo pauk]

Yep, maybe it would be the best to keep the 30mm away from the prop disc. BTW, there was a picture or two that supposedly showed the wing root installation of the MK 103 in the Fw-190 wing root?

BTW a 10% increase in velocity often needs 20% more propellant so a 20% increase is going to need over 40% more. Throw out everything and start over?

It is late 1940 - meaning a new gun for the new cartridge, ie. no historical MK 108.

For a gun that is used to best effect only on a V-12 powered Fw 190 airframe?

Nope - also for the Bf-109 and heavy/night fighters.

Germans had enough trouble with different guns and ammo as it was. FW units got electric primed 20mm ammo and 109 units got percussion (one reason for not mounting a single 20mm gun in a pod under the fuselage of the 109).

Opt for electrically-only primed MG 151/20 as soon as possible (it was available from Autumn of 1941?), should solve the case in reasonable time.

German Luftwaffe had 7.9mm, 13mm, 15mm, at least FOUR kinds of 20mm and at least 2 types of 30mm ammo in service in large numbers, not including experimental stuff. Fascinating to read about but a supply officers nightmare. Lets throw in the different types of projectiles for each ammunition type.
Lets also remember that the the Army used some different 20mm ammo.
Perhaps only the Japanese had such a complicated supply situation.

Nah, Soviets were the champions here - 3 LMG types, 2 HMG types, 2 x 20mm, 2 x 23 mm and 2 x 37mm, all service guns, for aircraft. Indeed a nightmare for the supply officer.
Anyway, the MG 151 (15 mm) gets canceled once the 20mm variant is in. The percussion-primed MG 151/20 will follow the suit soon. Not sure what to do with MG FF and MG 131 - the MG 151 cannot fit at any place where those can? MG 131 is actually running rather late for pre-1943 Luftwaffe - maybe neck it soon enough out to receive the 15mm shell?

 

[wiking85]

Why focus on cannons if they have R4Ms? Beyond that why not have a Sturmböcke type FW190F for ground attack with the MK108? It would have made a big mess against any soft ground target.

 

[Shortround6]

Yep, maybe it would be the best to keep the 30mm away from the prop disc. BTW, there was a picture or two that supposedly showed the wing root installation of the MK 103 in the Fw-190 wing root?

I believe it was a test rig, never flown? It may be where they discovered the problem of the big cases?

It is late 1940 - meaning a new gun for the new cartridge, ie. no historical MK 108.

Ok, but leads to.......

Nope - also for the Bf-109 and heavy/night fighters.

Mk 108 weighed 58kg, MK 103 weighed 141kg (down from the MK 101s 180kg) and a step up from the MG 151/20s 42kg. 60 rounds of short 30mm ammo weighs 28.8 kg, 150 rounds of 20x82 mine ammo weighs 27.5kg. 60 rounds of MK 103 ammo 46.8 kg. Japanese had some experimental 30mm guns but you are going to be dong very good to get the performance you want plus a decent rate of fire (something the Japanese guns lacked) for under 70-75kg and it may be closer to (or over) 80kg. Ammo will jump from 480 grams a round (not projectile) to around 600-650 grams a round.
Off course if your new gun merely splits the difference in weight between the MK 108 and MK 103 (100kg ?) you wind up with a bit of burden on the 109 and the lower powered night fighters. At least until you can get the DB 605 straightened out.

Opt for electrically-only primed MG 151/20 as soon as possible (it was available from Autumn of 1941?), should solve the case in reasonable time.

May depend on raw materials. Why didn't they go with the single under fuselage pod on the 109s? two 20mm and two mg 131s with less weight and drag than the 'gunboats'? of course ALL the twin engine aircraft got percussion primed ammo.

Nah, Soviets were the champions here - 3 LMG types, 2 HMG types, 2 x 20mm, 2 x 23 mm and 2 x 37mm, all service guns, for aircraft. Indeed a nightmare for the supply officer.

I was giving you different ammo types, not different guns. While different guns are a pain, if they use common ammo things are a lot easier. The 20mm MG FF cannot use MG FF/M ammo and vice versa. Granted some types of ammo were used only at the beginning of the war and faded quickly.


Anyway, the MG 151 (15 mm) gets canceled once the 20mm variant is in. The percussion-primed MG 151/20 will follow the suit soon. Not sure what to do with MG FF and MG 131 - the MG 151 cannot fit at any place where those can? MG 131 is actually running rather late for pre-1943 Luftwaffe - maybe neck it soon enough out to receive the 15mm shell?

even if the small 13x64 case will hold the 15mm projectile you don't have enough powder capacity to drive it at a worthwhile speed.

From Tony Williams Website.

 

[tomo pauk]

Why focus on cannons if they have R4Ms? Beyond that why not have a Sturmböcke type FW190F for ground attack with the MK108? It would have made a big mess against any soft ground target.

The rockets might make sense if one wants to kill bombers, but far less so for dealing with enemy fighters.

I believe it was a test rig, never flown? It may be where they discovered the problem of the big cases?

Might be; hopefully, some day the test results would surface.

Mk 108 weighed 58kg, MK 103 weighed 141kg (down from the MK 101s 180kg) and a step up from the MG 151/20s 42kg. 60 rounds of short 30mm ammo weighs 28.8 kg, 150 rounds of 20x82 mine ammo weighs 27.5kg. 60 rounds of MK 103 ammo 46.8 kg. Japanese had some experimental 30mm guns but you are going to be dong very good to get the performance you want plus a decent rate of fire (something the Japanese guns lacked) for under 70-75kg and it may be closer to (or over) 80kg. Ammo will jump from 480 grams a round (not projectile) to around 600-650 grams a round.
Off course if your new gun merely splits the difference in weight between the MK 108 and MK 103 (100kg ?) you wind up with a bit of burden on the 109 and the lower powered night fighters. At least until you can get the DB 605 straightened out.

Thanks for the numbers. The aim should be at approx 80 kg for the mid-power 30 mm cannon. FWIW, the MK 101/103 were using some 3.5 times as much of propellant as the MK 108 (110 grams vs. 30 g; both for the Mine shell ammo); casings were at 350 g vs. 115 g. An extra 15 g of propellant and maybe 70 g of the casings will make a new cartridge maybe 570 grams heavy?

May depend on raw materials. Why didn't they go with the single under fuselage pod on the 109s? two 20mm and two mg 131s with less weight and drag than the 'gunboats'? of course ALL the twin engine aircraft got percussion primed ammo.

Maybe it was due to the raw materials, electrically primed guns and ammo will require copper for some parts.

I was giving you different ammo types, not different guns. While different guns are a pain, if they use common ammo things are a lot easier. The 20mm MG FF cannot use MG FF/M ammo and vice versa. Granted some types of ammo were used only at the beginning of the war and faded quickly.

VVS used their, British and US light MGs; their and US heavy MG; their and British 20mm etc - that was my point. Multiplies by different ammo types for most of the guns.

even if the small 13x64 case will hold the 15mm projectile you don't have enough powder capacity to drive it at a worthwhile speed.
.

Yep, the 13mm was not that fast to begin with - 710 m/s for the 38.5 gram projectile, propellant weight 7.1 g. With 57 g heavy 15mm shell, we would be lucky to be above 600 m/s.

 

[wiking85]

The rockets might make sense if one wants to kill bombers, but far less so for dealing with enemy fighters.

Why do you need anything over 20mm for fighter killing?

 

[tomo pauk]

20mm is fine vs. fighters, but less than 2 or 3 might not suffice to kill a bomber. Carrying 3 or 4 x 20mm will impose a greater drag and weight penalty, while being less capable to bring down the said bomber than one or two 30 mm.
If we plan to carry, say, 2 dozens of R4M rockets and 2 x 20 mm, a sudden appearance of enemy fighters will force us to fire off the rockets instantly, in order to lessen the weight and drag; once those fighters are gone, the 20 mm will fail to make an impression to the bombers.