Since I'm kind of a technophile, I made up a large description of all the ideal equipment a German military would have during the period where the nazis historically controlled Germany. It's not necessarily meant to be the possible armament of Nazi Germany, it could be the armament of whatever government is in control of Germany during this period, but that's not its primary focus. I just wanted to see what the best equipment was for a 1930's Germany (yes, this is a German wank). Much of it is completely fictional, but I have tried to describe it in detail and keep it as realistic as I could, using only technology that was available or which could easily be developed.
If anyone wants to, they can make suggestions or use this in their TLs; I won't mind.
Overall Approach:
Germany, in 1932 would focus on the development of weapons that only provide a significant effectiveness improvement per ton over their predecessors. This means that simply making larger or more complex weapons would no longer be introduced for the sake of sophistication as before. In addition, the complex cancellations and changes in requirements of weapons (which wreaked havoc on german development and industry) would not be carried out as in real life, meaning that there would be no need for stopgaps to be developed. Instead, a clear development path based on relatively fixed requirements would be used for weapons and other industries.
For a start, things like the Autobahn would be constructed using more mass production methods across the board, unlike real life. The only exception would be dispersed industry which would be crucial to surviving bombing attacks. The other massive change would be the adoption of a military standard intermodal container very similar to the current ISO container, specified at 2.5 meters wide, 2.5 meters tall, and 7.5 meters in length. A smaller "half-length" container that was only 3.75 meters long was adopted to fit onto Opel Blitz trucks and smaller half-tracks, while still allowing 2 of them to be used in place of a full-length container on larger vehicles. These containers would be standardized in all military services, and would likely spread to the rest of the world from there, but most importantly they would give the army a massive logistics advantage.
Although the Autobahn's construction was more efficiently conducted with machines, its construction would actually be slowed down to focus on repairing and upgrading the German rail network, which had fallen into a barely serviceable state during and after WWI. An excellent new design of standardized locomotives, the Einheitsdampflokomotiven, had been created, but there had been barely any produced to replace the aging, incompatible locomotive fleet. Worse still, even if production ramped up, it would still take decades to replace the old rolling stock, due to insufficient production capacity for new locomotives to fill demand. In addition, it was estimated that during wartime, the country would ideally have a need for 60,000 locomotives, not including those lost to enemy attack or other forms of attrition.
To fix this problem, it was decided to build a new locomotive works of unprecedented size in the Ruhr valley, capable of producing (using the most modern mass production methods) 1,000 Einheitsdampflokomotiven a month at full capacity. This was as many as had been produced in total since 1925, and more than most plants could produce in a year at full capacity. This was an exception to the rule about dispersed industry and was immensely expensive, but it was well-defended with flak towers, and it proved capable of solving the rolling stock problems. It completely replaced all older locomotives 2 years after it was completed, and it could produce as many locomotives as the economy would require in war in just 5 years once up and running. Moreover, with the other plants freed from producing locomotives, they could focus on replacing the rest of the outdated and worn out rolling stock, replacing boxcars with container cars in the process.
At the same time, the rail lines used by the railroads were also in a state of extreme disrepair. Not only did the rail lines need to be repaired, they needed to be upgraded to a new standard capable of handling 20 ton axle loads, as required by the Einheitsdampflokomotiven. This could be done with much machine labor, but it was impossible to set up a dedicated factory to do this like the locomotive works. Instead, a massive sum of money was required to upgrade most of the rail network to the new standard, and electrify the main lines for high-speed and high-capacity trains. It was expensive, but required to fix the state of the rail lines. Even with the machines that saved cost, time, and labor, the Autobahn's completion was delayed until 1949.
Artillery/Infantry Weapons:
Several land-based artillery units were developed differently than in real life. Many were replaced by different weapons entirely, and the entire development process would be much smoother and less complex, with fewer dead end or useless projects. The first new artillery projects that were introduced in 1933 were the 10.5 cm K 18 and the 15 cm sFH 18. These guns had a modern split trail design and a large improvement in range over their predecessors, but with an increase in weight. While the resulting guns were satisfactory and served the Wehrmacht well, a similar design with more range was being developed in the USSR.
Immediately, a requirement for a successor design was put out, which was to match the Soviet designs in range and light weight, if not surpass them, without resorting to expensive light alloys. The resulting design, the sFH 40 (muzzle brake added to real life sFH 40) would be able to match the range of any similar field gun, making this weapon a replacement for not just the sFH 18, but also the 15 cm K 16. Its replacement was planned for 1939, but the design was found to be much heavier than the K 16 for only a slight increase in range. It did not even have a split trail, and it was found to be completely inferior to the new gun-howitzer in development. These new weapons would however not be in service until about 1939, but when they were, they were the equal of any design in the world. Added to this was a new shell based on the sub-caliber HE Triebspiegel rounds being developed for Flak. Instead of developing a new 10.5 cm gun based on the same carriage as the sFH 40, it was found that a sub-caliber 10.5 cm round that was fired out of the 15 cm howitzer's barrel could equal the muzzle velocity, and thus range, of a dedicated 10.5 cm field gun. This negated the need for 2 separate weapons on the same carriage, with considerable production and logistical savings.
Above: the 15cm sFH 40 adopted to replace the sFH 18.
At the same time, the 17 cm K 18 and 21 cm Mrs 18 were developed, with a world-beating dual-recoil carriage, but a lackluster design for the gun itself. A newer gun design was found to be more weight-efficient, and with new shell designs could combine the weight of the Mrs 18s shell with the range of the K 18 in a new 19 cm Haubitze 25. This new design began replacing older designs around 1942.
On the other end of the weight spectrum, the 2 new infantry gun prototypes were found to have no improvements over their counterparts. The 75 mm gun, the le.IG 18, was a conventional box trail design which weighed 400 kg, and could throw the same shell as fired by the Grosstraktor's 75 mm gun at roughly 210 m/s to a range of 3.5 km. By comparison, the Skoda 75 mm model 1915, a mountain gun used in WWI as an infantry gun by the Germans, weighed 613 kg, but in other respects was superior to the more “modern” le.IG 18. While it was considered somewhat flimsy by the Germans as a result of being a mountain gun designed to be broken into small loads, this feature required a special variant of the le.IG 18 for mountain troops which weighed 40 kg more than the base version. In addition, its shell was about the same weight, its muzzle velocity was 349 m/s compared to 210 m/s for the le.IG 18, and its range was over double that of the newer gun, 8,250 meters compared to 3,550 m. In addition, a modernized variant weighed 700 kg and raised the range still further to 8,700 m, but this was considered too much weight for the range increase. Still, it was enough to result in the le.IG 18 being rejected and replaced by a slightly redesigned and strengthened model 15 as a dual-purpose mountain, infantry, and light artillery gun, thus also replacing the FK 16 n.A, which had a similar weight, range, and rate of fire. Many were actually converted from existing WWI-era guns, saving money and precious industry compared to building new models.
The larger infantry gun, the sIG 33, was a massive 15 cm design that weighed 1,800 kg, and could fire a 15 cm 45 kg shell out to 4,700 m. This design had a conventional box trail, and thus, had no intrinsic advantage over the earlier heavy howitzer, the WWI-era 15 cm sFH 13, which weighed just 2,250 kg, and could fire the same 15 cm shell out to 8,600 m, due to its much higher muzzle velocity of 381 m/s, compared to just 240 m/s for the sIG 33. This design was revised to lower its weight to that of the sIG 33s level, using advances in design and production since WWI, and was thus adopted as a dual-purpose howitzer and infantry gun in place of the sIG 33. Like the Skoda M.15, many were modified from WWI-era stocks, again saving money and industrial capacity for other projects.
By 1936, however, the 7.5 cm gun was considered to still be outdated compared to more modern guns, and a replacement was sought in the form of the GebG 36, a mountain gun which weighed only about 750 kg, but had greater range than either the M.15 or even the FK 16 n.A. In fact, it even had as much range as the intended replacement of the FK 16, the FK 18. With the addition of the gun shield, it replaced the model 15 as the standard light artillery, mountain, and infantry gun of the Reichswehr.
For mortars, the 8 cm design was found to be as good as any in the world, but a new 120 mm mortar was being designed in Finland that promised to provide very heavy firepower at the battalion level, the 120 Krh/40. It was ready for service in 1935, and immediately ordered by the Reichswehr for battalion artillery. It was also found to make the 10 cm Nebelwerfer 35 chemical morter largely redundant. This saved considerable design effort, since not only did the Nebelwerfer 35 have too short of a range to meet its requirement, its replacement which would meet the requirement (the Nebelwerfer 40) was shaping up to be 8 times heavier, and still have less performance than the 120 Krh/40.
At the same time, the 5 cm Granatwerfer 36 infantry mortar prototype was found to be overweight and overcomplicated for its mission. Once again, foreign weapons proved a better option, when the Type 89 Grenade Discharger was ordered instead of it. It was a much lighter and simpler weapon, enough to be used at the platoon level. Moreover, its light bombs could be used as standard hand grenades, eliminating the need for the Model 39 Eierhandgranate then in development for infantry. There was still, however, a dedicated heavy mortar bomb developed for it, with no grenade functionality.
Above: the Type 89 Grenade Discharger and accessories, adopted in place of the complicated 5 cm mortar prototype
Added to this was a close copy of the Japanese Type 100 Grenade Discharger under development, which was similar to the German Schiessbecher also under development at the time. However, unlike the Schiessbecher, the Type 100 used the same standard hand grenade/mortar bomb as the Type 89, simplifying logistics, and it used a gas trap system. This meant that grenades could be launched with regular ammunition instead of blanks. Its superiority over the Schiessbecher clear at a cursory evaluation, it was adopted alongside the Type 89 by 1939.
Above: the Type 100 Grenade Discharger, adopted in place of the Schiessbecher
However, there were changes made to the infantry grenade by the Reichswehr. Testing revealed that the grenade contained too much explosive and not enough shrapnel effect, so it was redesigned along the lines of the “potato masher”, with a primarily “offensive” (thin casing w/ no fragmentation) design. This was to be supplemented by a fragmentation sleeve (Splitterring) when fragmentation was required. The fuse was also changed. Instead of a single 7-8 second setting optimized for mortar fire, but too long for grenade use, the fuse was electric, and had 2 settings that could be changed by removing a small cap on the top of the grenade. This would change the fuse from 7-8 seconds to 5 seconds, making it a much more practical grenade. The detachable propellant chamber was retained so that it could still be used as a mortar bomb. The smoke and flare grenades were largely unaffected.
The 10.5 cm howitzers that were used were identical to those used in real life, but development was much faster, so that the leFH 18M was in service by 1936, which was in turn replaced by the GebH 40 mountain howitzer which weighed less and was just as powerful otherwise. However, the GebH 40 had no shield and used many light alloys, so it was replaced in ordinary artillery battalions by the leFH 18/40 after 1940.
Anti-tank guns, on the other hand, mostly progressed as they would in real life, from the Pak 36, to the Pak 38, to the Pak 40, but in 1943 modification was made that increased its elevation to 30 degrees, and allowed the Pak 40 to double as a field gun with a 13,300 m range. This far exceeded even the range of the FK 38 gun that was exported to Brazil (essentially a longer barreled FK 18), for roughly the same weight. It began entering service by 1942 as the Pak 40M(in real life it was the FK 7M59, which only existed in prototype form). In addition, the gun was standardized with the vehicle-mounted KwK 40 from the beginning, with an l/48 barrel and fatter, shorter cartridges used by the KwK variant. After the Pak 40 came the Pak 43, with its effective cruciform mount and high velocity, and the Pak 44 dual-purpose field and heavy antitank gun. All anti-tank guns used interchangeable ammunition with their tank gun counterparts, using the same electrical primers as the tank and anti-aircraft shells to allow a common supply of ammunition for both anti-tank and tank guns.
The larger caliber single-shot flak in the army remained unchanged from real life, with the exception of the 12.8 cm flak gun. This gun was not adopted in favor of a 15 cm gun which was just as immobile, but much more deadly, and had interchangeable ammunition with its naval counterpart. This will be discussed further in the naval section.
In the smaller-caliber automatic flak, however, there were significant changes. The 2 cm Flak 30 had given satisfactory service since 1930 in the navy (as the 2 cm C/30), and since 1934 in the army. By 1936, however, the army had requested a somewhat faster-firing weapon, and Rheinmetall proposed a faster-firing derivative known as the 2 cm Flak 38. The Reichswehr, however, noticed that Rheinmetalls' subsidiary Solothurn produced a select-fire version of an anti-tank rifle called the Solothurn S-18/1000. This rifle fired the same ammunition from the same clips as the Flak 30/38, and weighed less than the Flak 38 (53.5 kg vs 57.5 kg). Its select-fire variant, the S-18/1100 fired slightly faster than the Flak 38, had a dedicated lightweight AA mount to maximize stability and accuracy when in automatic fire against aircraft, and could be disassembled into the rifle barrel, rifle, and some mount components for easy transport by paratroops and mountain troops. Moreover, without its AA mount, it still served as an anti-tank rifle, making it a type of universal weapon.
Above: the Solothurn S-18/1100 in AA and AT mounting. Note the way the rifle is slung beneath the AA mount
With all of this in its favor, the Solothurn S-18/1100 was adopted instead of the Flak 38 (and it would also obviate development of other anti-tank rifles like the sPzB 41). While it was phased out as the primary flak of the army with the advent of 3.7 cm flak, it remained in use by paratroopers and mountain troops due to its light weight and portability, and by regular troops as a heavy sniper rifle. It was also adopted by the navy in single and double mounts as last-ditch AA weapons.
At about the same time the S-18/1100 was adopted, Rheinmetall also proposed a quadruple Flak 38 “Flakvierling,” but this was found to be just as heavy as a single 3.7 cm flak mount, while having about half the overall effectiveness, and so it was rejected by both the army and navy. The 3.7 cm flak itself had undergone a change in ammunition before entering service at the insistence of the army and navy, namely switching to a 3.7 cm cartridge with a slightly longer case, a much wider shoulder and thus case, much larger propellant charge, and thus much better muzzle velocity. As they came into service, the 3.7 cm flak became the primary close-range AA weapon of both the army and navy.
Even with this, however, there was a medium-range AA requirement, specifically for an automatic flak of about 5 cm caliber. Rheinmetall responded by scaling up the 3.7 cm Flak 36 to produce the 5 cm Flak 38 (the real-life 5 cm Flak 41), but it was top-heavy, underpowered, had slow traverse, and would blind the gunner. The entire project was practically restarted as the 5.5 cm Gerat 58 in 1939, and this weapon was finally successful, being accepted as the 5.5 cm Flak 42 in 1942. Meanwhile, an even heavier automatic flak was required, resulting in the weapon being scaled up to produce the 7.5 cm Flak 45 in 1945. This weapon was better known for its role in the navy than its role in the army, being extremely heavy.
The infantry weapons remained roughly the same, but the Kar 98k weapon would soon be replaced by the MP 40 (the StG 44 in real life) in 1940, and the real life MP 40 would never see service, the MP 38 being the end of the line for the Reichswehr's submachine guns. In addition, a combination light machine gun, paratrooper rifle, and sniper rifle firing the full-power 7.92 mm cartridge would enter service as the FG 40 (the real life FG 42). In 1943, a further MP 43 (the real life StG 45) entered service and replaced the MP 40, and a weapon built on similar operating principles (the real life Stgw 57/ SIG SG 510) chambered for the full-power cartridge designated the FG 44 replaced the FG 40.
In 1942, a new infantry weapon, designated the Faustpatrone, and soon improved to what was known as the Panzerfaust, entered service. By 1944, this had evolved into the Panzerfaust 150 series, which could be reused, and by 1945, the Panzerfaust 250 series was in service with a much improved sight and foregrip. By 1940, a weapon known as the Panzershreck, consisting of an 80 mm tube which could be reloaded with a rocket, was also in service. It was used to supplement both antitank and infantry guns.
The parachutes used by paratroops were developed from the start to use the 2-point shoulder harness used by most countries, rather than the single-point back harness developed by the Italians for their paratroops. This enabled heavier loads to be carried on drops.
Land Vehicles:
The Reichswehr ordered 300 Leichttraktors in 1931, but this was cancelled in real life the next year due to new requirements for an interim tank that became the Panzer I. The tanks that it would be an interim for were the Panzer III and Panzer IV, which initially had no armament improvements over their Leichttraktor and Grosstraktor counterparts.
In my timeline, the cancellation was reviewed, and the Leichttraktor was found to be only inferior in speed to the proposed “interim” Panzer I, and was the equal of the proposed medium tank in firepower with a 4-man crew and 37 mm tank gun. With a new suspension experimentally fitted in 1933, the speed actually increased to 40 kph, its original design specification. It was realized that this early tank was a much better vehicle than the training-only light tanks. In fact, it was considered that a single Leichttraktor was the equal of 3 Panzer 1 prototypes. Similar conclusions were reached about the Grosstraktor, which was ordered into production in 1932 alongside the renewed Leichttraktor. These tanks were not perfect, but were effective in combat, though not as much as the later Panzer I variants.
Above: the variant of the Leichttraktor adopted for production
Since these tanks were already prototyped, there was no need for the real life Panzer I and II interim tanks which were inferior to these tanks anyway. The development of the Panzer I, which would be designed to fit turrets to fulfill the medium and heavy tank requirements (in real life filled by the Panzer III and IV), could be given full development attention as it would not enter service for some time. When it did enter service, it did so as the Panzer IA, with 30 mm of sloped hull armor and the Leichttraktor's 37 mm anti-tank gun, and as the Panzer IB, with the same 75 mm infantry support gun as the Grosstraktor. Both variants shared a Maybach diesel powerplant of 300 HP and a weight of around 22 tons and a 5-man crew built around the concept of a 3-man turret.
The Panzer IA was soon upgunned to a 50 mm gun and redesignated the Panzer IC, and a later upgrade to replace both the Panzer IB and IC with a tank armored to 50mm and armed with a long-barreled 75 mm gun, was designated the Panzer ID.
When a still more powerful tank was required, the 650HP Maybach diesel engine with a tunnel crankshaft, elegantly engineered to fit inside a small package, was fitted in a novel transverse installation in 1941 to create the Panzer IIA. This was intended, unlike the Panzer I, to be a universal (infantry support and cruiser role) tank with a long-barreled very high-velocity Kwk 42 75 mm gun from the start, 80 mm of sloped hull armor, a more space-efficient hexagonal “Schmalturm,” and a rear-mounted transmission. This last feature was important, as it eliminated the requirement that the transmission run under the tank, increasing its silhouette. This also allowed the elimination of hull sponsons over the tracks, making the tank easier to mass-produce. A “heavy” variant with 100 mm of sloped hull armor and an 88 mm l/56 gun built around the famous Flak gun of the same caliber, as well as thickened 120 mm turret armor, was designated the Panzer IIB.
When these guns were also considered to be in danger of being outclassed, the Reichswehr again upgraded the medium tank to feature 100 mm of hull armor, an uprated 900HP Maybach turbocharged diesel, 120 mm of turret armor, and a longer 88 mm L/71 gun based on an improved anti-aircraft gun with a much higher muzzle velocity. It was designated the Panzer IIC. The heavy tank was similarly upgraded with 150 mm of hull armor, 180 mm of frontal turret armor, and the same 88mm L/71 gun. This variant was designated the Panzer IID.
These tanks also served as the basis for a series of tank destroyers (in the case of the panzer I, initially mounting a 75 mm long gun, and later a 75 mm high-velocity gun) and anti-aircraft guns. The Flakpanzer I SPAAG initially mounted a 37 mm cannon, and later a twin mount was developed in an open turret. The Panzer II tank destroyer initially mounted a long 88 mm L/71 gun, and was later replaced by the upgraded model outright. The Flakpanzer II SPAAG initially mounted a twin 5 cm flak gun, and was later upgunned to a twin 7.5 cm flak gun as soon as it was available. This later model also had its own radar system and was just as automated as its towed counterpart. In addition, Leichttraktor, Grosstraktor, Panzer I, and later Panzer II chassis were used as the basis for all manner of self-propelled artillery, usually in the form of the 7.5 cm field gun or the 10.5 cm howitzer mounted on the Leichttraktor chassis, the 15 cm howitzer or 10.5 cm field gun mounted on the Grosstraktor or Panzer I chassis, and finally the 17 cm field gun or 21 cm howitzer mounted on the Panzer II chassis. These formed the basis of German armored forces.
During the development of the Panzer II, a lighter vehicle was also viewed to be required to replace earlier Panzer I based vehicles that did not require a heavier vehicle. This resulted in the Panzer L 20, a lightweight 20 ton vehicle that used what was essentially half of the Maybach 650 HP diesel that produced 300 HP, and was also transversely mounted. When the Panzer IIC and IID were introduced, the L 20 was also upgraded with a 400 HP engine. These tanks were used for a lightweight SPAAG that mounted a twin 30 mm aircraft cannon (the MK 101), and a tank destroyer that used the 75 mm L/70 gun in a casemate. Additionally, a self-propelled artillery vehicle that could mount a detachable version of a 7.5 cm field gun, a 10.5 cm howitzer, a 15 cm howitzer, or the 10.5 cm field gun was produced based on the L 20. However, the potential firepower of the vehicle was considered wasted when used with a 7.5 cm field gun or 10.5 cm howitzer. An armored personnel carrier version was also produced in 1944.
Half-tracks were also used extensively in both armored personnel carrier and unarmored applications, but in only 4 variants. The unarmored chassis families that they were based on were designated the SdKfz 2, 3, 4, and 5, respectively. They were used for all manner of functions, from anti-aircraft vehicles, to bunker destroyers (in the SdKfz 5-based Bunkerflak variant), to recovery vehicles, to self-propelled artillery mounts. Later on, these were extensively standardized to use the same parts, and could mount different towed weapons on the same basic flatbed. This simplified production down to just the personnel carrier, cargo carrier, armored personnel carrier, multipurpose flatbed, and armored multipurpose flatbed variants of each halftrack family. Much like the artillery vehicles, their weapons could be detached and used as towed weapons. Later on, containerization meant that the larger cargo carrier variants were replaced by multipurpose flatbed variants.
For wheeled vehicles, the Opel Blitz was standardized as the Reichswehr's heavy truck from the start, with the Mercedes-Benz 3000 being only produced for civilian use, and it would be replaced on the production line by more Blitz' in case of war. To make the Blitz more versatile, it switched to a more efficient diesel engine, as per requirements, and a simple and easy to maintain 4-wheel drive system was also added to the truck. A heavier 4x6 5-ton version of the Blitz was produced with a more powerful engine, and this supplemented the Blitz for heavier loads, and eased the demands on the large half-tracks. The overall Einheits-PKW program was never carried out, and the VW Kubelwagen was developed and in service by 1936 instead, with half-tracks and Blitz trucks filling out most other logistical roles required. A multipurpose semi-trailer tractor heavier and more powerful than the Blitz was also produced to haul containers, and this proved very common. At about the same time, the multipurpose flatbed variant of the Blitz was modified to carry a half-length intermodal container, and it rapidly replaced the regular cargo variant of the Blitz.
Notes:
1. The Panzer I would be similar to a diesel-powered Panzer III/IV in real life, and 30mm sloped armor- which was standard in the early German WWII tanks.
2. The Panzer II's engine arrangement is almost identical to that of the T-44, T-54, T-62, and T-72, which saved a lot of space.
3. The Maybach 300HP engine is similar to the real life HL120TRM, but with diesel power. The Maybach 650HP and 900HP engines are similar to the real life HL210 and HL234 engines, but again with diesel power. Historically, Maybach used their tank engine experience to make efficient tunnel crankcase locomotive diesels after WWII, so they are definitely capable of producing diesels using their engine technology.
4. German guns 75mm guns are divided into 3 groups: the 75mm short-barreled or short gun, the 75mm long-barreled or long gun, and the 75mm high-velocity or L/70 gun. The short gun is equal to the KwK 37, the long gun is equal to the KwK 40 L/48, and the high-velocity gun is equal to the KwK 42. Also, all tank guns have fully interchangeable ammunition with anti-tank guns- that means the 75mm anti-tank gun uses the same ammunition as the 75mm long gun.
Luftwaffe:
Above: the Ju 88A, the Luftwaffe's mainstay twin-engine aircraft from 1939 to 1943.
The Luftwaffe was created from scratch after German economic recovery and rearmament began. As in real life, the Bf 109 and He 111 were created and adopted, but the Do 17 and later Do 217 were not adopted due to being somewhat redundant with the He 111 itself. The Ju 88 and many other bombers like the He 177 were never required to do dive bombing, resulting in them entering service by 1938. In addition, the Bf 110 was replaced by the Ju 88 on the production lines as soon as possible. The proposed Me 210 (and 410) were rejected as not being significant upgrades and were not designed or produced. The Fw 190 began production in 1940, and unlike real life, its ground attack potential was recognized from the start, and it replaced the Ju 87 on the production lines as soon as the engine supplies were sufficient. As for the Bf 109, the Bf 109 F and later models allowed room for 2 MG151/20s in the wing slots formerly occupied by the MG FF guns, rather than leaving them empty as in real life.
Above: The Ju 288 with 2,200 KW (3,000 HP) Jumo 222C engines
The Jumo 222 gasoline engine had a much faster and smoother development cycle than in real life, allowing them to power the Ju 288, replacing the He 177, the He 111, and the Ju 88 as a “universal” bomber with world-beating performance. The FW 190D went into production with these engines as well in 1943 when sufficient engines could be spared from the Ju 288 (whose production began the year previously). Though the Ju 288 made an excellent bomber, it was less agile than its predecessors, making it a poor heavy fighter, fighter-bomber, or night fighter. In these roles they were replaced by the Dornier P.59 (also Jumo 222-powered unlike real life), soon designated the Do 335, and also offering world-beating performance and very heavy armament in its many variants. It, like the newer Fw 190 variants, went into production in 1943.
For most other aircraft, diesel propulsion wass preferred to save weight. This produced a high demand for the Jumo 204/205 series of engines, the only successful diesel engines then in production. In turn, most airliners and flying boats (later used for reconnaissance) utilized some form of these engines, and as a result light aviation engines like the Bramo 323 never made it into production, or were replaced whenever possible by diesel engines. The increased interest in Junkers' diesel engines increased the development cycle for them, resulting in the derivative Jumo 223 developed by 1942, and its successor the Jumo 224 being in production by 1943.
The Luftwaffe's transport aircraft consisted of the Ju 52 until about 1938, when they began to be replaced by the Ju 252, powered by Jumo 205 engines rather than its predecessors' BMW R132 engines. This produced more range, but the aircraft was still not satisfactory. In 1942, a dramatically improved aircraft known as the Arado Ar 232 began to enter production. It was powered by 4 Junkers Jumo 208 engines, the most powerful variants of the Jumo to enter service (and a significant difference from the real life Ar 232). It also had a rear ramp, a high wing, 11 sets of wheels to help with soft field landing, and a high tail that allowed ease of loading. It became the primary transport aircraft of the Luftwaffe from around 1943 onwards. After 1943, the Ar 232 B entered service, with 2 Jumo 223 engines replacing the Jumo 208 engines, and in 1944 it was further upgraded to the Ar 232 C with 2 Jumo 224 engines, giving a huge boost in lifting capacity.
Above: the Ar 232 B, with 2 Jumo 223 diesel engines
Notes:
1. The Photo of the Ar 232 is in fact that of a prototype that used 2 BMW 801 engines, not Jumo 223's.
Navy:
In the navy, as the Deutschland class is being introduced, a new demand to consolidate secondary batteries into a single dual-purpose battery produced a new requirement. Since the 12.8 cm flak guns in a dual-purpose role would represent a reduction in firepower over the 15 cm guns in anti-surface engagements, the new requirement was issued as a request for a 15 cm flak gun, with the same traverse and elevation rates (and similar rates of fire) as the earlier dedicated flak guns. What resulted was a gun similar to the 15 cm Gerat 60 or 65 prototypes in real life. To make these guns most effective, they were to be designed in enclosed gun turrets, but using triple mounts to save weight per gun. The mounting, as required, was also able to be used in a new destroyer design to succeed the 1934 class destroyers.
Above: The 15 cm flak gun prototype used as a basis for the new dual-purpose secondary gun.
Almost all new ships after the Deutschlands and 1934 destroyers were redesigned to accommodate newer technologies that the “Old Guard” in the navy had rejected earlier for a variety of reasons. These technologies were triple and quadruple gun turrets, diesel propulsion, dual-purpose guns with power ramming, and torpedo tubes mounted on the sides of gun turrets. All of these innovations saved considerable space and weight (and thus cost), and thus increased the effectiveness per ton of ships considerably. In fact, the diesel propulsion requirement went further than just the navy; all land or sea vehicles designed after 1932 would be required to have diesel engines for efficient use of fuel, and weight savings on ships. However, most land vehicles used 4-stroke diesels while ships usually used only 2-stroke engines. Still, the requirement to use diesels spurred development, and the increased testing rapidly eliminated most faults from diesel engine designs, more so than real life.
The Deutschlands themselves were considered good boats however, and the innovations now required were either already present or could be refitted onto the ships later. Since they were only 10 to 12 thousand tons, they were about the same size as light cruisers (particularly those later during WWII), but carried much heavier armament, and still had reasonably good speed. In fact, they could outgun all heavy gun cruisers built with the exception of the Alaska class, and possibly the Des Moines class cruisers, which were much heavier. With improved engines, they would be able to match those cruisers in speed as well. By making an improved Deutschland (which was the same 10-12,000 tons displacement) the standard light cruiser, the Reichsmarine gained a cruiser that was much more powerful than any of its peers throughout the 1940s.
The improved 15 cm gun turret, with 10rpm (through power ramming), 15 degrees per second traverse and elevation speeds, and an enclosed 3-gun mounting, was first tested on Deutschland in 1936. This gun turret weighed close to 100 tons, but was no heavier than the combined weight of the guns it replaced. Since 4 triple turrets (2 on each side) were replacing the 8 single 15 cm mounts on the side of Deutschland, and the 3 dual 10.5 cm flak mounts on the ship, this represented a 50% increase in anti-ship secondary firepower and an exponential increase in anti-aircraft firepower for the same weight. In reality the increase in anti-ship secondary firepower was even greater due to the increase in rate of fire of the guns over their manually rammed counterparts. These improvements would be standard-built on all new Deutschland-class light cruisers, as well as being retrofitted to the older ships.
Weight and complexity were further saved by replacing the aft torpedo tubes with 3 torpedo tubes (stacked vertically) mounted on each side of 2 of the secondary turrets. This meant that the rearmost secondary turrets (1 on each side) mounted 6 torpedo tubes on each side of the ship, instead of 4, in addition to a net increase in deck space and a reduction in complexity (the torpedo mounts were now fixed to the turret, instead of requiring their own rotating mounts).
The new destroyer class following the 1934 class would be diesel powered like the Deutschlands, and would use 2 of the Deutschland's new secondary turrets as its primary turrets (with less armor, of course). Both of these would have 6 torpedo tubes mounted on each of them, and they would be laid out with one turret at each end of the ship, much like a miniature Deutschland. This would give the destroyer a 6 gun and 12 torpedo broadside. Smaller caliber AA guns, like the Deutschland, would consist of 37 mm and 20 mm guns, concentrated into as many guns per mount as possible to minimize the number of mounts. After evaluation, the Reichsmarine's planned semi-automatic 37 mm Flak (the SK C/30) was found to be hopelessly ineffective. It was cancelled and replaced by its fully automatic Army counterpart, the Flak 36 (this was true for all ships that planned to use them).
In addition to this, a destroyer escort was planned, much like the real life Elbing class multipurpose torpedo boats. This would carry a diesel propulsion plant, and would carry only 1 turret of the same type that the destroyers and refitted Deutschlands would carry. This was designed to be a cheap escort and patrol vessel, much like the smaller (and unchanged from real life) Schnellboote patrol boats.
A heavy cruiser or Battlecruiser was contemplated until the advent of the french Dunkerque class battleship. This ship was only about 26,000 tons, but was superior to any comparable battlecruiser, and easily superior to its equivalent tonnage in heavy cruisers. It was decided to build a light battleship class that would both counter the Dunkerques and take advantage of the traits offered by this new class of warship. With the usual diesel propulsion (though it would take some time to develop such a powerful engine), the ship was essentially to a diesel-powered welded counterpart to the Dunkerques. It featured new quadruple gun turrets for its main weapons, and unlike the Deutschlands, was well armored to resist hits from the main weapon of that ship class. In addition, since its main armament was 2 quadruple turrets mounted front, all 4 secondary turrets were mounted aft, 2 on each side facing forward, and 2 superfiring over the rear of the ship. Its secondary turrets were the same as on the Deutschlands, but with torpedo tubes only on the side-mounted turrets. This was similar to the real life layout intended for the Richelieu class battleship Clemenceau. The main guns were of 35 cm caliber, and the designed speed was 31 knots.
Finally a main battleship used 38 cm guns in a 40,000 ton design reminiscent of the french Alsace class battleships. 3 quadruple turrets similar to those of the light battleship allowed for 12 guns, and diesel engines (some of the largest ever constructed at the time) allowed for a speed of 31 knots. The main armament was arranged with 2 turrets superfiring front, and 1 mounted aft, with the now-usual 15 cm turrets as secondary mountings. 3 such turrets were mounted on the centerline, with 2 superfiring over the rear main turret and 1 superfiring over the front main turrets. 2 more secondary turrets with torpedo tubes were mounted on the sides facing forwards, for a total of 15 secondary 15 cm dual-purpose guns. The small-caliber AA armament consisted of 37 mm aa guns in quadruple mountings placed around the superstructure only.
As time progressed the quadruple 37 mm guns were progressively replaced by twin automatic 5 cm and later 7.5 cm AA guns, similar to the US 3”/50 AA gun. This design significantly improved their performance against air targets.
It is worth examining the diesel engines used for larger ships at this point. While they did take years to develop, much time was saved by recovering old documents about a 12,000 HP prototype 6-cylinder engine produced before and during WWI. This engine was produced by MAN, and although it was intended for use in a battleship all along, it was scrapped at the end of WWI under the Versailles Treaty. Its designs and the original designers, however, were still at MAN, and they updated the new design with modern technology like direct fuel injection, and doubled the banks to create a 30,000 HP V-12 marine diesel. Four of these were used for the light battleship, and five were in the main battleship.
Above: the WWI-era prototype maritime diesel used as the basis for battleship engines.
The torpedoes themselves were standard G7 torpedoes until a Japanese technology exchange brought the pure oxygen Type 93 24” torpedo to the attention of the Reichsmarine. A competing design was quickly developed by Hellmuth Walter using hydrogen peroxide, which was ultimately selected to replace the standard G7 torpedo in both 24” ship-launched and 21” submarine-launched versions.
The submarines themselves went through the standard design process of the Type VII and Type IX families, followed by the Type XX submarine (the real life Type XXI submarine), which however was fully developed and in service by 1942. This was due to early patronage and support of Hellmuth Walter's air-independent propulsion concept, which resulted in the earlier development of a Type XVII equivalent, and an earlier battery-powered development which became the Type XX. The other important addition was that of the snorkel, developed from Dutch designs in the 1930's and fully developed for installation on existing and new submarines by 1939.
When the Reichsmarine was experimenting with amphibious operations around 1938, several significant shortcomings were noted, notably the extreme difficulty associated with landing troops and equipment without significant risk to themselves or their transports. Fortunately, the Japanese already had plenty of experience in amphibious warfare in China, and had developed several new warship designs to land troops quickly and effectively in the face of enemy resistance. The most obvious of these were the Daihatsu-class landing craft with its good seakeeping and bow ramp, and its larger counterpart, the Toku Daihatsu-class landing craft, intended for vehicle cargo. In addition to this, they had developed a support boat with a small size and shallow draft for close range fire support during landing operations, known as the AB-Tei class support vessel. To carry all of this, a large amphibious assault vessel had been built. Known as the Shinshu Maru, the 8,000 ton vessel had a well deck for carrying and launching the landing craft and support vessels it carried, as well as a catapult for launching its complement of aircraft.
In addition to the specifications and designs for these ships, the Japanese gave access to 2 newer designs that they had been working on since 1937. Created as a response to perceived shortcomings in their landing craft during operations in China, the new designs were intended to land larger numbers of troops than the earlier designs. The first design, intended to succeed the Shinshu Maru, took that ship's well deck and added a full-length flight deck for aircraft to take off (but not land) from. The resultant 11,000 ton ship (the Akitsu Maru) resembled an aircraft carrier, but without a hangar, and a well deck for launching 29 landing craft and 4 support vessels, like its predecessor.
Above: the Akitsu Maru, the basis for similar German vessels. Note the crane blocking one end of the flight deck (rectified in German designs) and the closed well deck doors at the stern of the ship
The other new design, the SS-1, was intended to land heavy equipment, including tanks, directly onto the shore rapidly. It's 900 ton hull was based on the design of icebreakers so that it could beach itself, and open its bow doors to unload all of its heavy cargo straight onto beaches. While these 2 new designs were still in the development phase, their plans were made available to the Reichsmarine.
Above: the SS-1 landing ship, on which German designs were based. Note the bow doors for offloading cargo
With these designs, the navy expanded the marines, and set about adapting the newest Japanese designs for their uses. This would result in adopting variants of the Daihatsu, the Toku Daihatsu, the AB-Tei, the SS-1, and the Akitsu Maru-class warships. The small landing craft and the SS-1 landing ship were largely unchanged, save for switching to welded construction and diesel propulsion (standard for all ships by this point), and the only major change to the AB-Tei class was to swap the turret for one based on that of the Panzer I. However, the large 11,000 ton amphibious assault ship was virtually redesigned, adopting a hangar deck beneath the flight deck to store aircraft and an arrestor hook to recover as well as launch small aircraft like the Fi 156 or Bf 109 (no bombers though). It still retained a well deck that could carry and launch 30 Daihatsu equivalents, 5 Toku Daihatsu equivalents, and 4 AB-Tei equivalents. It additionally carried a regiment of marines and their equipment ready to deploy.
EDIT 6/26/16: shortened the length of the intermodal container from 9 m to 7.5 m (9m is way too long even for a semi-trailer), added the half-length container, added the 15 cm land-based flak, and cleaned up some of the grammar.
2nd EDIT 6/27/16: Added the heavy Opel Blitz 6x4 variant, changed the tractor trailer variant into a separate vehicle, gave the Opel Blitz a new diesel engine and primitive 4-wheel drive, and increased the weight of the naval 15 cm triple turret from 80 to 100 tons.
3rd EDIT 6/27/16: Changed Faustpatrone service entry date from 1936 to 1942, the Panzerfaust 150 service entry date from 1942 to 1944, and the Panzerfaust 250 service entry date from 1944 to 1945
4th EDIT 6/29/16: Major edit. Added section on railroad repair, changed the SK C/30 from being replaced by the 3.7 cm Flak C/30 to being cancelled in favor of it before entering service, added submarine snorkel, added section about adopting Japanese amphibious warfare vessels, added sections on mortars, grenade launchers, grenades, added leFH 18/40 instead of just GebH 40, and added sections on light automatic flak
5th EDIT 6/30/16: Changed photos of 2 cm flak from Solothurn S5-100 to Solothurn S-18/1100. Added references to Solothurn photos
6th EDIT 7/2/16: Major edit. Added Luftwaffe section, added designation for the 5 cm mortar prototype and Eierhandgranate
7th EDIT 7/2/16: Added appendixes and Do-335 to supplement the Ju 288 in the 1943 era Luftwaffe aircraft.
8th EDIT 7/8/16: Added section on subcaliber rounds for the sFH 40.
Sources:
http://www.aviarmor.net/tww2/tanks/germany/leichtetraktor.htm - the leichttraktor complete history
http://en.valka.cz/topic/view/66995/15-cm-sFH-40 - the heavy howitzer sFH 40
http://www.gwpda.org/naval/proppl.htm - the history of diesel propulsion in the German navy up until WWI
http://www.practicalmachinist.com/v...esel-engines-battleships-99-years-ago-162819/ - the diesel engines used as a basis for the battleship propulsion
https://weaponsandwarfare.com/15-cm-flak-50-55-60-60f/ - the 15 cm flak gun prototypes
http://en.valka.cz/topic/view/38878/15-cm-Gerat-50 -more information on 15 cm flak guns
https://www.flickr.com/photos/massimofoti/sets/72157624866330321/with/5005902994/ - photos of with Solothurn S-18/1100 in AA mount in Swiss museum
http://forum.axishistory.com/viewtopic.php?t=136241&start=15 - more photos and info on Solothurn S-18/1100
Appendix
my more in-depth posts on this thread that go into context about some part of the main post
Appendix 1: Fixing the state of the German rail network and rolling stock:
It seems that coal is still a good basis for the modernized railway, perhaps with main lines being electrified for supplementary high-speed trains and heavy usage (it's more efficient to burn coal in a power plant and send pure electricity to the train than it is to transport the coal to the train and burn it there). Still, I wasn't aware of how bad the entire German rail system was at that point. Not only was only a tiny fraction of the rail network up to the new standards requiring a 20 ton axle load, but most of the rolling stock was non-standardized WWI-era (if not earlier) locomotives and wagons. These conditions persisted right up through WWII. Since the modern, standardized Einheitsdampflokomotiven (German for Standard Steam Locomotives) constituted only 1/25 of the rolling stock in 1934 (1,000 out of ~25,000), and even with the simplified Kriegslokomotiven and a massive effort reached barely 1/3 of the rolling stock by the end of WWII (14,500 out of ~45,000), it's safe to say that even if production was ramped up, the production capacity won't be enough. Overall, while I think the Einheitsdampflokomotiven and the the similar electric trains were good designs (I can't think of many improvements to them- they're already standardized and efficient), there isn't enough production capacity to build them or lay new standardized track (with 20 ton max axle load). The German locomotive fleet stood at around 25,000 in 1934, and even at the end of WWII its increase to 45,000 locomotives, it was likely woefully inadequate. I suspect that ultimately the German wartime rail network would ideally be using over 60,000 locomotives, a number that could not be attained with existing infrastructure.
To solve this problem, I think the best solution would be to take advantage of mass production techniques and construct an unprecedented (for the time) new locomotive works somewhere in Germany, capable of mass-producing (using the most modern techniques) at least 1,000 Einheitsdampflokomotiven per month. To put this into perspective, only a handful of German locomotive works (perhaps a half-dozen) made this many Einheitsdampflokomotiven (including Kriegslokomotiven) in the entirety of the period from 1933 to 1945. This would be much like the equivalent of the Tesla Gigafactory for the locomotive world at the time. It would be able to replace the entirety of Germany's outdated non-standardized stock within 2 years, and fulfill Germany's wartime rolling stock requirements within 5 years. It would be immensely expensive, and very vulnerable to air attack (so it would likely have to have its own flak towers defending it, along with fighters), but it's the only method I see that can fix Germany's rolling stock problems in a reasonable period of time. Also, less impressive but no less important, is the requirement to start a new program to upgrade and repair as many of the German rail lines to the new standard as possible, preferably using machine labor wherever possible to save time, manpower, and cost.
With the locomotive manufacturing taken care of by the new works, the existing locomotive works can set to work replacing the older non-locomotive rolling stock, replacing boxcars with container wagons in the process.
Appendix 2: Japanese amphibious assault technology pre-Guadalcanal campaign
As for the landing craft, I found surprisingly advanced equipment that could be adopted from the Japanese at this time. Their amphibious equipment was far more advanced than I expect even the best case Germany could develop during this time, so in this TL they would base their designs off Japanese ones.
The landing craft would be the Daihatsu-class, famous as the inspiration for the LCVP "Higgins Boats." However, the Japanese also produced several other advanced designs. One of these was simply a larger Daihatsu, named the Toku Daihatsu-class. These were scaled up so that they could carry a medium tank (about 16 tons for Japanese designs) or heavier cargo. Of course, both designs were superior in many ways to their US counterparts. They had twin skegs beneath the hull for stability, they had markedly better seakeeping, they had diesel propulsion, and had steel construction so they were much tougher than the Higgins.
Above: US wartime identification manual on the Daihatsu and Toku Daihatsu-class landing craft
In addition to this, the AB-Tei class support vessel displaced 30 tons, carried 2 machine gun turrets and a 57 mm-armed tank turret, and were intended to provide close-in fire support during landing operations. While they saw more use as river gunboats, they performed their intended role well during amphibious assaults.
Above: 2 AB-Tei class support vessels
The larger vessels were even more modern, with the Shinshu Maru being the world's first amphibious assault ship. She looked like, and had all the features of, a modern Amphibious Transport Dock, including a well deck with storage for 29 Daihatsu-class landing craft, 25 smaller Shohatsu-class landing craft (which were being replaced by the Daihatsu-class anyway), 4 AB-Tei class support vessels, and a catapult with a complement of 29 aircraft. However, the aircraft were expected to land on captured airfields; there were no landing provisions on the ship.
Above: the Shinshu Maru and her well deck in the process of launching a landing craft (presumably during the Second Sino-Japanese War)
Her successor was the Akitsu Maru, which entered service in 1942 (though she was designed since 1937), and had a full length flight deck for autogyros in addition to the well deck of the Shinshu Maru, making her resemble an aircraft carrier, or modern Wasp-class Amphibious Assault Ship. This ship carried autogyros that could return to the ship, but lacked arrestor wires for landing proper aircraft. Still, this qualifies the Akitsu Maru as the world's first Landing Helicopter Dock. Later ships had similar features, but were converted from existing merchant ships, and entered service late in the war.
For Tank Landing Ships, a design was developed following experience in amphibious operations in China. This design was known as the SS-1 class amphibious assault ships, and it featured a bow door for unloading a lot of heavy cargo quickly. The ship resembled a US Landing Ship Tank, but was somewhat smaller. Still, after the Guadalcanal Campaign, the project, which was given low priority up until then, was cancelled in favor of a design based on an enlarged US Landing Ship Tank (the No. 101 class). Still, all of these designs would be available to Germany, should they wish to base their own designs on them (which they will in this TL).
Sources:
http://forums.ubi.com/showthread.ph...(like-me))?s=64347046df05f6dd38205bb67abc8a14 - information on Japanese small landing craft
http://pwencycl.kgbudge.com/D/a/Daihatsu_class.htm - information on the Daihatsu-class landing craft
http://pwencycl.kgbudge.com/T/o/Toku_Daihatsu_class.htm - information on the Toku Daihatsu-class landing craft
http://pwencycl.kgbudge.com/S/s/SS-1_class.htm - information on the SS-1 class landing ships
http://www.navypedia.org/ships/japan/jap_aux_ss.htm - more information on the SS-1 class landing ships
http://pwencycl.kgbudge.com/A/b/AB-Tei_class.htm - information on the AB-Tei class support ships
http://www.combinedfleet.com/Shinshu_t.htm - information on the Shinshu Maru
http://pwencycl.kgbudge.com/S/h/Shinshu_Maru_class.htm - more information on the Shinshu Maru
http://www.combinedfleet.com/Akitsu_t.htm - information on the Akitsu Maru
http://pwencycl.kgbudge.com/A/k/Akitsu_Maru_class.htm - more information on the Akitsu Maru
http://www.combinedfleet.com/Hatsudotei_c.htm - list of major Japanese amphibious vessels of WWII
If anyone wants to, they can make suggestions or use this in their TLs; I won't mind.
Overall Approach:
Germany, in 1932 would focus on the development of weapons that only provide a significant effectiveness improvement per ton over their predecessors. This means that simply making larger or more complex weapons would no longer be introduced for the sake of sophistication as before. In addition, the complex cancellations and changes in requirements of weapons (which wreaked havoc on german development and industry) would not be carried out as in real life, meaning that there would be no need for stopgaps to be developed. Instead, a clear development path based on relatively fixed requirements would be used for weapons and other industries.
For a start, things like the Autobahn would be constructed using more mass production methods across the board, unlike real life. The only exception would be dispersed industry which would be crucial to surviving bombing attacks. The other massive change would be the adoption of a military standard intermodal container very similar to the current ISO container, specified at 2.5 meters wide, 2.5 meters tall, and 7.5 meters in length. A smaller "half-length" container that was only 3.75 meters long was adopted to fit onto Opel Blitz trucks and smaller half-tracks, while still allowing 2 of them to be used in place of a full-length container on larger vehicles. These containers would be standardized in all military services, and would likely spread to the rest of the world from there, but most importantly they would give the army a massive logistics advantage.
Although the Autobahn's construction was more efficiently conducted with machines, its construction would actually be slowed down to focus on repairing and upgrading the German rail network, which had fallen into a barely serviceable state during and after WWI. An excellent new design of standardized locomotives, the Einheitsdampflokomotiven, had been created, but there had been barely any produced to replace the aging, incompatible locomotive fleet. Worse still, even if production ramped up, it would still take decades to replace the old rolling stock, due to insufficient production capacity for new locomotives to fill demand. In addition, it was estimated that during wartime, the country would ideally have a need for 60,000 locomotives, not including those lost to enemy attack or other forms of attrition.
To fix this problem, it was decided to build a new locomotive works of unprecedented size in the Ruhr valley, capable of producing (using the most modern mass production methods) 1,000 Einheitsdampflokomotiven a month at full capacity. This was as many as had been produced in total since 1925, and more than most plants could produce in a year at full capacity. This was an exception to the rule about dispersed industry and was immensely expensive, but it was well-defended with flak towers, and it proved capable of solving the rolling stock problems. It completely replaced all older locomotives 2 years after it was completed, and it could produce as many locomotives as the economy would require in war in just 5 years once up and running. Moreover, with the other plants freed from producing locomotives, they could focus on replacing the rest of the outdated and worn out rolling stock, replacing boxcars with container cars in the process.
At the same time, the rail lines used by the railroads were also in a state of extreme disrepair. Not only did the rail lines need to be repaired, they needed to be upgraded to a new standard capable of handling 20 ton axle loads, as required by the Einheitsdampflokomotiven. This could be done with much machine labor, but it was impossible to set up a dedicated factory to do this like the locomotive works. Instead, a massive sum of money was required to upgrade most of the rail network to the new standard, and electrify the main lines for high-speed and high-capacity trains. It was expensive, but required to fix the state of the rail lines. Even with the machines that saved cost, time, and labor, the Autobahn's completion was delayed until 1949.
Artillery/Infantry Weapons:
Several land-based artillery units were developed differently than in real life. Many were replaced by different weapons entirely, and the entire development process would be much smoother and less complex, with fewer dead end or useless projects. The first new artillery projects that were introduced in 1933 were the 10.5 cm K 18 and the 15 cm sFH 18. These guns had a modern split trail design and a large improvement in range over their predecessors, but with an increase in weight. While the resulting guns were satisfactory and served the Wehrmacht well, a similar design with more range was being developed in the USSR.
Immediately, a requirement for a successor design was put out, which was to match the Soviet designs in range and light weight, if not surpass them, without resorting to expensive light alloys. The resulting design, the sFH 40 (muzzle brake added to real life sFH 40) would be able to match the range of any similar field gun, making this weapon a replacement for not just the sFH 18, but also the 15 cm K 16. Its replacement was planned for 1939, but the design was found to be much heavier than the K 16 for only a slight increase in range. It did not even have a split trail, and it was found to be completely inferior to the new gun-howitzer in development. These new weapons would however not be in service until about 1939, but when they were, they were the equal of any design in the world. Added to this was a new shell based on the sub-caliber HE Triebspiegel rounds being developed for Flak. Instead of developing a new 10.5 cm gun based on the same carriage as the sFH 40, it was found that a sub-caliber 10.5 cm round that was fired out of the 15 cm howitzer's barrel could equal the muzzle velocity, and thus range, of a dedicated 10.5 cm field gun. This negated the need for 2 separate weapons on the same carriage, with considerable production and logistical savings.
Above: the 15cm sFH 40 adopted to replace the sFH 18.
At the same time, the 17 cm K 18 and 21 cm Mrs 18 were developed, with a world-beating dual-recoil carriage, but a lackluster design for the gun itself. A newer gun design was found to be more weight-efficient, and with new shell designs could combine the weight of the Mrs 18s shell with the range of the K 18 in a new 19 cm Haubitze 25. This new design began replacing older designs around 1942.
On the other end of the weight spectrum, the 2 new infantry gun prototypes were found to have no improvements over their counterparts. The 75 mm gun, the le.IG 18, was a conventional box trail design which weighed 400 kg, and could throw the same shell as fired by the Grosstraktor's 75 mm gun at roughly 210 m/s to a range of 3.5 km. By comparison, the Skoda 75 mm model 1915, a mountain gun used in WWI as an infantry gun by the Germans, weighed 613 kg, but in other respects was superior to the more “modern” le.IG 18. While it was considered somewhat flimsy by the Germans as a result of being a mountain gun designed to be broken into small loads, this feature required a special variant of the le.IG 18 for mountain troops which weighed 40 kg more than the base version. In addition, its shell was about the same weight, its muzzle velocity was 349 m/s compared to 210 m/s for the le.IG 18, and its range was over double that of the newer gun, 8,250 meters compared to 3,550 m. In addition, a modernized variant weighed 700 kg and raised the range still further to 8,700 m, but this was considered too much weight for the range increase. Still, it was enough to result in the le.IG 18 being rejected and replaced by a slightly redesigned and strengthened model 15 as a dual-purpose mountain, infantry, and light artillery gun, thus also replacing the FK 16 n.A, which had a similar weight, range, and rate of fire. Many were actually converted from existing WWI-era guns, saving money and precious industry compared to building new models.
The larger infantry gun, the sIG 33, was a massive 15 cm design that weighed 1,800 kg, and could fire a 15 cm 45 kg shell out to 4,700 m. This design had a conventional box trail, and thus, had no intrinsic advantage over the earlier heavy howitzer, the WWI-era 15 cm sFH 13, which weighed just 2,250 kg, and could fire the same 15 cm shell out to 8,600 m, due to its much higher muzzle velocity of 381 m/s, compared to just 240 m/s for the sIG 33. This design was revised to lower its weight to that of the sIG 33s level, using advances in design and production since WWI, and was thus adopted as a dual-purpose howitzer and infantry gun in place of the sIG 33. Like the Skoda M.15, many were modified from WWI-era stocks, again saving money and industrial capacity for other projects.
By 1936, however, the 7.5 cm gun was considered to still be outdated compared to more modern guns, and a replacement was sought in the form of the GebG 36, a mountain gun which weighed only about 750 kg, but had greater range than either the M.15 or even the FK 16 n.A. In fact, it even had as much range as the intended replacement of the FK 16, the FK 18. With the addition of the gun shield, it replaced the model 15 as the standard light artillery, mountain, and infantry gun of the Reichswehr.
For mortars, the 8 cm design was found to be as good as any in the world, but a new 120 mm mortar was being designed in Finland that promised to provide very heavy firepower at the battalion level, the 120 Krh/40. It was ready for service in 1935, and immediately ordered by the Reichswehr for battalion artillery. It was also found to make the 10 cm Nebelwerfer 35 chemical morter largely redundant. This saved considerable design effort, since not only did the Nebelwerfer 35 have too short of a range to meet its requirement, its replacement which would meet the requirement (the Nebelwerfer 40) was shaping up to be 8 times heavier, and still have less performance than the 120 Krh/40.
At the same time, the 5 cm Granatwerfer 36 infantry mortar prototype was found to be overweight and overcomplicated for its mission. Once again, foreign weapons proved a better option, when the Type 89 Grenade Discharger was ordered instead of it. It was a much lighter and simpler weapon, enough to be used at the platoon level. Moreover, its light bombs could be used as standard hand grenades, eliminating the need for the Model 39 Eierhandgranate then in development for infantry. There was still, however, a dedicated heavy mortar bomb developed for it, with no grenade functionality.
Above: the Type 89 Grenade Discharger and accessories, adopted in place of the complicated 5 cm mortar prototype
Added to this was a close copy of the Japanese Type 100 Grenade Discharger under development, which was similar to the German Schiessbecher also under development at the time. However, unlike the Schiessbecher, the Type 100 used the same standard hand grenade/mortar bomb as the Type 89, simplifying logistics, and it used a gas trap system. This meant that grenades could be launched with regular ammunition instead of blanks. Its superiority over the Schiessbecher clear at a cursory evaluation, it was adopted alongside the Type 89 by 1939.
Above: the Type 100 Grenade Discharger, adopted in place of the Schiessbecher
However, there were changes made to the infantry grenade by the Reichswehr. Testing revealed that the grenade contained too much explosive and not enough shrapnel effect, so it was redesigned along the lines of the “potato masher”, with a primarily “offensive” (thin casing w/ no fragmentation) design. This was to be supplemented by a fragmentation sleeve (Splitterring) when fragmentation was required. The fuse was also changed. Instead of a single 7-8 second setting optimized for mortar fire, but too long for grenade use, the fuse was electric, and had 2 settings that could be changed by removing a small cap on the top of the grenade. This would change the fuse from 7-8 seconds to 5 seconds, making it a much more practical grenade. The detachable propellant chamber was retained so that it could still be used as a mortar bomb. The smoke and flare grenades were largely unaffected.
The 10.5 cm howitzers that were used were identical to those used in real life, but development was much faster, so that the leFH 18M was in service by 1936, which was in turn replaced by the GebH 40 mountain howitzer which weighed less and was just as powerful otherwise. However, the GebH 40 had no shield and used many light alloys, so it was replaced in ordinary artillery battalions by the leFH 18/40 after 1940.
Anti-tank guns, on the other hand, mostly progressed as they would in real life, from the Pak 36, to the Pak 38, to the Pak 40, but in 1943 modification was made that increased its elevation to 30 degrees, and allowed the Pak 40 to double as a field gun with a 13,300 m range. This far exceeded even the range of the FK 38 gun that was exported to Brazil (essentially a longer barreled FK 18), for roughly the same weight. It began entering service by 1942 as the Pak 40M(in real life it was the FK 7M59, which only existed in prototype form). In addition, the gun was standardized with the vehicle-mounted KwK 40 from the beginning, with an l/48 barrel and fatter, shorter cartridges used by the KwK variant. After the Pak 40 came the Pak 43, with its effective cruciform mount and high velocity, and the Pak 44 dual-purpose field and heavy antitank gun. All anti-tank guns used interchangeable ammunition with their tank gun counterparts, using the same electrical primers as the tank and anti-aircraft shells to allow a common supply of ammunition for both anti-tank and tank guns.
The larger caliber single-shot flak in the army remained unchanged from real life, with the exception of the 12.8 cm flak gun. This gun was not adopted in favor of a 15 cm gun which was just as immobile, but much more deadly, and had interchangeable ammunition with its naval counterpart. This will be discussed further in the naval section.
In the smaller-caliber automatic flak, however, there were significant changes. The 2 cm Flak 30 had given satisfactory service since 1930 in the navy (as the 2 cm C/30), and since 1934 in the army. By 1936, however, the army had requested a somewhat faster-firing weapon, and Rheinmetall proposed a faster-firing derivative known as the 2 cm Flak 38. The Reichswehr, however, noticed that Rheinmetalls' subsidiary Solothurn produced a select-fire version of an anti-tank rifle called the Solothurn S-18/1000. This rifle fired the same ammunition from the same clips as the Flak 30/38, and weighed less than the Flak 38 (53.5 kg vs 57.5 kg). Its select-fire variant, the S-18/1100 fired slightly faster than the Flak 38, had a dedicated lightweight AA mount to maximize stability and accuracy when in automatic fire against aircraft, and could be disassembled into the rifle barrel, rifle, and some mount components for easy transport by paratroops and mountain troops. Moreover, without its AA mount, it still served as an anti-tank rifle, making it a type of universal weapon.
Above: the Solothurn S-18/1100 in AA and AT mounting. Note the way the rifle is slung beneath the AA mount
With all of this in its favor, the Solothurn S-18/1100 was adopted instead of the Flak 38 (and it would also obviate development of other anti-tank rifles like the sPzB 41). While it was phased out as the primary flak of the army with the advent of 3.7 cm flak, it remained in use by paratroopers and mountain troops due to its light weight and portability, and by regular troops as a heavy sniper rifle. It was also adopted by the navy in single and double mounts as last-ditch AA weapons.
At about the same time the S-18/1100 was adopted, Rheinmetall also proposed a quadruple Flak 38 “Flakvierling,” but this was found to be just as heavy as a single 3.7 cm flak mount, while having about half the overall effectiveness, and so it was rejected by both the army and navy. The 3.7 cm flak itself had undergone a change in ammunition before entering service at the insistence of the army and navy, namely switching to a 3.7 cm cartridge with a slightly longer case, a much wider shoulder and thus case, much larger propellant charge, and thus much better muzzle velocity. As they came into service, the 3.7 cm flak became the primary close-range AA weapon of both the army and navy.
Even with this, however, there was a medium-range AA requirement, specifically for an automatic flak of about 5 cm caliber. Rheinmetall responded by scaling up the 3.7 cm Flak 36 to produce the 5 cm Flak 38 (the real-life 5 cm Flak 41), but it was top-heavy, underpowered, had slow traverse, and would blind the gunner. The entire project was practically restarted as the 5.5 cm Gerat 58 in 1939, and this weapon was finally successful, being accepted as the 5.5 cm Flak 42 in 1942. Meanwhile, an even heavier automatic flak was required, resulting in the weapon being scaled up to produce the 7.5 cm Flak 45 in 1945. This weapon was better known for its role in the navy than its role in the army, being extremely heavy.
The infantry weapons remained roughly the same, but the Kar 98k weapon would soon be replaced by the MP 40 (the StG 44 in real life) in 1940, and the real life MP 40 would never see service, the MP 38 being the end of the line for the Reichswehr's submachine guns. In addition, a combination light machine gun, paratrooper rifle, and sniper rifle firing the full-power 7.92 mm cartridge would enter service as the FG 40 (the real life FG 42). In 1943, a further MP 43 (the real life StG 45) entered service and replaced the MP 40, and a weapon built on similar operating principles (the real life Stgw 57/ SIG SG 510) chambered for the full-power cartridge designated the FG 44 replaced the FG 40.
In 1942, a new infantry weapon, designated the Faustpatrone, and soon improved to what was known as the Panzerfaust, entered service. By 1944, this had evolved into the Panzerfaust 150 series, which could be reused, and by 1945, the Panzerfaust 250 series was in service with a much improved sight and foregrip. By 1940, a weapon known as the Panzershreck, consisting of an 80 mm tube which could be reloaded with a rocket, was also in service. It was used to supplement both antitank and infantry guns.
The parachutes used by paratroops were developed from the start to use the 2-point shoulder harness used by most countries, rather than the single-point back harness developed by the Italians for their paratroops. This enabled heavier loads to be carried on drops.
Land Vehicles:
The Reichswehr ordered 300 Leichttraktors in 1931, but this was cancelled in real life the next year due to new requirements for an interim tank that became the Panzer I. The tanks that it would be an interim for were the Panzer III and Panzer IV, which initially had no armament improvements over their Leichttraktor and Grosstraktor counterparts.
In my timeline, the cancellation was reviewed, and the Leichttraktor was found to be only inferior in speed to the proposed “interim” Panzer I, and was the equal of the proposed medium tank in firepower with a 4-man crew and 37 mm tank gun. With a new suspension experimentally fitted in 1933, the speed actually increased to 40 kph, its original design specification. It was realized that this early tank was a much better vehicle than the training-only light tanks. In fact, it was considered that a single Leichttraktor was the equal of 3 Panzer 1 prototypes. Similar conclusions were reached about the Grosstraktor, which was ordered into production in 1932 alongside the renewed Leichttraktor. These tanks were not perfect, but were effective in combat, though not as much as the later Panzer I variants.
Above: the variant of the Leichttraktor adopted for production
Since these tanks were already prototyped, there was no need for the real life Panzer I and II interim tanks which were inferior to these tanks anyway. The development of the Panzer I, which would be designed to fit turrets to fulfill the medium and heavy tank requirements (in real life filled by the Panzer III and IV), could be given full development attention as it would not enter service for some time. When it did enter service, it did so as the Panzer IA, with 30 mm of sloped hull armor and the Leichttraktor's 37 mm anti-tank gun, and as the Panzer IB, with the same 75 mm infantry support gun as the Grosstraktor. Both variants shared a Maybach diesel powerplant of 300 HP and a weight of around 22 tons and a 5-man crew built around the concept of a 3-man turret.
The Panzer IA was soon upgunned to a 50 mm gun and redesignated the Panzer IC, and a later upgrade to replace both the Panzer IB and IC with a tank armored to 50mm and armed with a long-barreled 75 mm gun, was designated the Panzer ID.
When a still more powerful tank was required, the 650HP Maybach diesel engine with a tunnel crankshaft, elegantly engineered to fit inside a small package, was fitted in a novel transverse installation in 1941 to create the Panzer IIA. This was intended, unlike the Panzer I, to be a universal (infantry support and cruiser role) tank with a long-barreled very high-velocity Kwk 42 75 mm gun from the start, 80 mm of sloped hull armor, a more space-efficient hexagonal “Schmalturm,” and a rear-mounted transmission. This last feature was important, as it eliminated the requirement that the transmission run under the tank, increasing its silhouette. This also allowed the elimination of hull sponsons over the tracks, making the tank easier to mass-produce. A “heavy” variant with 100 mm of sloped hull armor and an 88 mm l/56 gun built around the famous Flak gun of the same caliber, as well as thickened 120 mm turret armor, was designated the Panzer IIB.
When these guns were also considered to be in danger of being outclassed, the Reichswehr again upgraded the medium tank to feature 100 mm of hull armor, an uprated 900HP Maybach turbocharged diesel, 120 mm of turret armor, and a longer 88 mm L/71 gun based on an improved anti-aircraft gun with a much higher muzzle velocity. It was designated the Panzer IIC. The heavy tank was similarly upgraded with 150 mm of hull armor, 180 mm of frontal turret armor, and the same 88mm L/71 gun. This variant was designated the Panzer IID.
These tanks also served as the basis for a series of tank destroyers (in the case of the panzer I, initially mounting a 75 mm long gun, and later a 75 mm high-velocity gun) and anti-aircraft guns. The Flakpanzer I SPAAG initially mounted a 37 mm cannon, and later a twin mount was developed in an open turret. The Panzer II tank destroyer initially mounted a long 88 mm L/71 gun, and was later replaced by the upgraded model outright. The Flakpanzer II SPAAG initially mounted a twin 5 cm flak gun, and was later upgunned to a twin 7.5 cm flak gun as soon as it was available. This later model also had its own radar system and was just as automated as its towed counterpart. In addition, Leichttraktor, Grosstraktor, Panzer I, and later Panzer II chassis were used as the basis for all manner of self-propelled artillery, usually in the form of the 7.5 cm field gun or the 10.5 cm howitzer mounted on the Leichttraktor chassis, the 15 cm howitzer or 10.5 cm field gun mounted on the Grosstraktor or Panzer I chassis, and finally the 17 cm field gun or 21 cm howitzer mounted on the Panzer II chassis. These formed the basis of German armored forces.
During the development of the Panzer II, a lighter vehicle was also viewed to be required to replace earlier Panzer I based vehicles that did not require a heavier vehicle. This resulted in the Panzer L 20, a lightweight 20 ton vehicle that used what was essentially half of the Maybach 650 HP diesel that produced 300 HP, and was also transversely mounted. When the Panzer IIC and IID were introduced, the L 20 was also upgraded with a 400 HP engine. These tanks were used for a lightweight SPAAG that mounted a twin 30 mm aircraft cannon (the MK 101), and a tank destroyer that used the 75 mm L/70 gun in a casemate. Additionally, a self-propelled artillery vehicle that could mount a detachable version of a 7.5 cm field gun, a 10.5 cm howitzer, a 15 cm howitzer, or the 10.5 cm field gun was produced based on the L 20. However, the potential firepower of the vehicle was considered wasted when used with a 7.5 cm field gun or 10.5 cm howitzer. An armored personnel carrier version was also produced in 1944.
Half-tracks were also used extensively in both armored personnel carrier and unarmored applications, but in only 4 variants. The unarmored chassis families that they were based on were designated the SdKfz 2, 3, 4, and 5, respectively. They were used for all manner of functions, from anti-aircraft vehicles, to bunker destroyers (in the SdKfz 5-based Bunkerflak variant), to recovery vehicles, to self-propelled artillery mounts. Later on, these were extensively standardized to use the same parts, and could mount different towed weapons on the same basic flatbed. This simplified production down to just the personnel carrier, cargo carrier, armored personnel carrier, multipurpose flatbed, and armored multipurpose flatbed variants of each halftrack family. Much like the artillery vehicles, their weapons could be detached and used as towed weapons. Later on, containerization meant that the larger cargo carrier variants were replaced by multipurpose flatbed variants.
For wheeled vehicles, the Opel Blitz was standardized as the Reichswehr's heavy truck from the start, with the Mercedes-Benz 3000 being only produced for civilian use, and it would be replaced on the production line by more Blitz' in case of war. To make the Blitz more versatile, it switched to a more efficient diesel engine, as per requirements, and a simple and easy to maintain 4-wheel drive system was also added to the truck. A heavier 4x6 5-ton version of the Blitz was produced with a more powerful engine, and this supplemented the Blitz for heavier loads, and eased the demands on the large half-tracks. The overall Einheits-PKW program was never carried out, and the VW Kubelwagen was developed and in service by 1936 instead, with half-tracks and Blitz trucks filling out most other logistical roles required. A multipurpose semi-trailer tractor heavier and more powerful than the Blitz was also produced to haul containers, and this proved very common. At about the same time, the multipurpose flatbed variant of the Blitz was modified to carry a half-length intermodal container, and it rapidly replaced the regular cargo variant of the Blitz.
Notes:
1. The Panzer I would be similar to a diesel-powered Panzer III/IV in real life, and 30mm sloped armor- which was standard in the early German WWII tanks.
2. The Panzer II's engine arrangement is almost identical to that of the T-44, T-54, T-62, and T-72, which saved a lot of space.
3. The Maybach 300HP engine is similar to the real life HL120TRM, but with diesel power. The Maybach 650HP and 900HP engines are similar to the real life HL210 and HL234 engines, but again with diesel power. Historically, Maybach used their tank engine experience to make efficient tunnel crankcase locomotive diesels after WWII, so they are definitely capable of producing diesels using their engine technology.
4. German guns 75mm guns are divided into 3 groups: the 75mm short-barreled or short gun, the 75mm long-barreled or long gun, and the 75mm high-velocity or L/70 gun. The short gun is equal to the KwK 37, the long gun is equal to the KwK 40 L/48, and the high-velocity gun is equal to the KwK 42. Also, all tank guns have fully interchangeable ammunition with anti-tank guns- that means the 75mm anti-tank gun uses the same ammunition as the 75mm long gun.
Luftwaffe:
Above: the Ju 88A, the Luftwaffe's mainstay twin-engine aircraft from 1939 to 1943.
The Luftwaffe was created from scratch after German economic recovery and rearmament began. As in real life, the Bf 109 and He 111 were created and adopted, but the Do 17 and later Do 217 were not adopted due to being somewhat redundant with the He 111 itself. The Ju 88 and many other bombers like the He 177 were never required to do dive bombing, resulting in them entering service by 1938. In addition, the Bf 110 was replaced by the Ju 88 on the production lines as soon as possible. The proposed Me 210 (and 410) were rejected as not being significant upgrades and were not designed or produced. The Fw 190 began production in 1940, and unlike real life, its ground attack potential was recognized from the start, and it replaced the Ju 87 on the production lines as soon as the engine supplies were sufficient. As for the Bf 109, the Bf 109 F and later models allowed room for 2 MG151/20s in the wing slots formerly occupied by the MG FF guns, rather than leaving them empty as in real life.
Above: The Ju 288 with 2,200 KW (3,000 HP) Jumo 222C engines
The Jumo 222 gasoline engine had a much faster and smoother development cycle than in real life, allowing them to power the Ju 288, replacing the He 177, the He 111, and the Ju 88 as a “universal” bomber with world-beating performance. The FW 190D went into production with these engines as well in 1943 when sufficient engines could be spared from the Ju 288 (whose production began the year previously). Though the Ju 288 made an excellent bomber, it was less agile than its predecessors, making it a poor heavy fighter, fighter-bomber, or night fighter. In these roles they were replaced by the Dornier P.59 (also Jumo 222-powered unlike real life), soon designated the Do 335, and also offering world-beating performance and very heavy armament in its many variants. It, like the newer Fw 190 variants, went into production in 1943.
For most other aircraft, diesel propulsion wass preferred to save weight. This produced a high demand for the Jumo 204/205 series of engines, the only successful diesel engines then in production. In turn, most airliners and flying boats (later used for reconnaissance) utilized some form of these engines, and as a result light aviation engines like the Bramo 323 never made it into production, or were replaced whenever possible by diesel engines. The increased interest in Junkers' diesel engines increased the development cycle for them, resulting in the derivative Jumo 223 developed by 1942, and its successor the Jumo 224 being in production by 1943.
The Luftwaffe's transport aircraft consisted of the Ju 52 until about 1938, when they began to be replaced by the Ju 252, powered by Jumo 205 engines rather than its predecessors' BMW R132 engines. This produced more range, but the aircraft was still not satisfactory. In 1942, a dramatically improved aircraft known as the Arado Ar 232 began to enter production. It was powered by 4 Junkers Jumo 208 engines, the most powerful variants of the Jumo to enter service (and a significant difference from the real life Ar 232). It also had a rear ramp, a high wing, 11 sets of wheels to help with soft field landing, and a high tail that allowed ease of loading. It became the primary transport aircraft of the Luftwaffe from around 1943 onwards. After 1943, the Ar 232 B entered service, with 2 Jumo 223 engines replacing the Jumo 208 engines, and in 1944 it was further upgraded to the Ar 232 C with 2 Jumo 224 engines, giving a huge boost in lifting capacity.
Above: the Ar 232 B, with 2 Jumo 223 diesel engines
Notes:
1. The Photo of the Ar 232 is in fact that of a prototype that used 2 BMW 801 engines, not Jumo 223's.
Navy:
In the navy, as the Deutschland class is being introduced, a new demand to consolidate secondary batteries into a single dual-purpose battery produced a new requirement. Since the 12.8 cm flak guns in a dual-purpose role would represent a reduction in firepower over the 15 cm guns in anti-surface engagements, the new requirement was issued as a request for a 15 cm flak gun, with the same traverse and elevation rates (and similar rates of fire) as the earlier dedicated flak guns. What resulted was a gun similar to the 15 cm Gerat 60 or 65 prototypes in real life. To make these guns most effective, they were to be designed in enclosed gun turrets, but using triple mounts to save weight per gun. The mounting, as required, was also able to be used in a new destroyer design to succeed the 1934 class destroyers.
Above: The 15 cm flak gun prototype used as a basis for the new dual-purpose secondary gun.
Almost all new ships after the Deutschlands and 1934 destroyers were redesigned to accommodate newer technologies that the “Old Guard” in the navy had rejected earlier for a variety of reasons. These technologies were triple and quadruple gun turrets, diesel propulsion, dual-purpose guns with power ramming, and torpedo tubes mounted on the sides of gun turrets. All of these innovations saved considerable space and weight (and thus cost), and thus increased the effectiveness per ton of ships considerably. In fact, the diesel propulsion requirement went further than just the navy; all land or sea vehicles designed after 1932 would be required to have diesel engines for efficient use of fuel, and weight savings on ships. However, most land vehicles used 4-stroke diesels while ships usually used only 2-stroke engines. Still, the requirement to use diesels spurred development, and the increased testing rapidly eliminated most faults from diesel engine designs, more so than real life.
The Deutschlands themselves were considered good boats however, and the innovations now required were either already present or could be refitted onto the ships later. Since they were only 10 to 12 thousand tons, they were about the same size as light cruisers (particularly those later during WWII), but carried much heavier armament, and still had reasonably good speed. In fact, they could outgun all heavy gun cruisers built with the exception of the Alaska class, and possibly the Des Moines class cruisers, which were much heavier. With improved engines, they would be able to match those cruisers in speed as well. By making an improved Deutschland (which was the same 10-12,000 tons displacement) the standard light cruiser, the Reichsmarine gained a cruiser that was much more powerful than any of its peers throughout the 1940s.
The improved 15 cm gun turret, with 10rpm (through power ramming), 15 degrees per second traverse and elevation speeds, and an enclosed 3-gun mounting, was first tested on Deutschland in 1936. This gun turret weighed close to 100 tons, but was no heavier than the combined weight of the guns it replaced. Since 4 triple turrets (2 on each side) were replacing the 8 single 15 cm mounts on the side of Deutschland, and the 3 dual 10.5 cm flak mounts on the ship, this represented a 50% increase in anti-ship secondary firepower and an exponential increase in anti-aircraft firepower for the same weight. In reality the increase in anti-ship secondary firepower was even greater due to the increase in rate of fire of the guns over their manually rammed counterparts. These improvements would be standard-built on all new Deutschland-class light cruisers, as well as being retrofitted to the older ships.
Weight and complexity were further saved by replacing the aft torpedo tubes with 3 torpedo tubes (stacked vertically) mounted on each side of 2 of the secondary turrets. This meant that the rearmost secondary turrets (1 on each side) mounted 6 torpedo tubes on each side of the ship, instead of 4, in addition to a net increase in deck space and a reduction in complexity (the torpedo mounts were now fixed to the turret, instead of requiring their own rotating mounts).
The new destroyer class following the 1934 class would be diesel powered like the Deutschlands, and would use 2 of the Deutschland's new secondary turrets as its primary turrets (with less armor, of course). Both of these would have 6 torpedo tubes mounted on each of them, and they would be laid out with one turret at each end of the ship, much like a miniature Deutschland. This would give the destroyer a 6 gun and 12 torpedo broadside. Smaller caliber AA guns, like the Deutschland, would consist of 37 mm and 20 mm guns, concentrated into as many guns per mount as possible to minimize the number of mounts. After evaluation, the Reichsmarine's planned semi-automatic 37 mm Flak (the SK C/30) was found to be hopelessly ineffective. It was cancelled and replaced by its fully automatic Army counterpart, the Flak 36 (this was true for all ships that planned to use them).
In addition to this, a destroyer escort was planned, much like the real life Elbing class multipurpose torpedo boats. This would carry a diesel propulsion plant, and would carry only 1 turret of the same type that the destroyers and refitted Deutschlands would carry. This was designed to be a cheap escort and patrol vessel, much like the smaller (and unchanged from real life) Schnellboote patrol boats.
A heavy cruiser or Battlecruiser was contemplated until the advent of the french Dunkerque class battleship. This ship was only about 26,000 tons, but was superior to any comparable battlecruiser, and easily superior to its equivalent tonnage in heavy cruisers. It was decided to build a light battleship class that would both counter the Dunkerques and take advantage of the traits offered by this new class of warship. With the usual diesel propulsion (though it would take some time to develop such a powerful engine), the ship was essentially to a diesel-powered welded counterpart to the Dunkerques. It featured new quadruple gun turrets for its main weapons, and unlike the Deutschlands, was well armored to resist hits from the main weapon of that ship class. In addition, since its main armament was 2 quadruple turrets mounted front, all 4 secondary turrets were mounted aft, 2 on each side facing forward, and 2 superfiring over the rear of the ship. Its secondary turrets were the same as on the Deutschlands, but with torpedo tubes only on the side-mounted turrets. This was similar to the real life layout intended for the Richelieu class battleship Clemenceau. The main guns were of 35 cm caliber, and the designed speed was 31 knots.
Finally a main battleship used 38 cm guns in a 40,000 ton design reminiscent of the french Alsace class battleships. 3 quadruple turrets similar to those of the light battleship allowed for 12 guns, and diesel engines (some of the largest ever constructed at the time) allowed for a speed of 31 knots. The main armament was arranged with 2 turrets superfiring front, and 1 mounted aft, with the now-usual 15 cm turrets as secondary mountings. 3 such turrets were mounted on the centerline, with 2 superfiring over the rear main turret and 1 superfiring over the front main turrets. 2 more secondary turrets with torpedo tubes were mounted on the sides facing forwards, for a total of 15 secondary 15 cm dual-purpose guns. The small-caliber AA armament consisted of 37 mm aa guns in quadruple mountings placed around the superstructure only.
As time progressed the quadruple 37 mm guns were progressively replaced by twin automatic 5 cm and later 7.5 cm AA guns, similar to the US 3”/50 AA gun. This design significantly improved their performance against air targets.
It is worth examining the diesel engines used for larger ships at this point. While they did take years to develop, much time was saved by recovering old documents about a 12,000 HP prototype 6-cylinder engine produced before and during WWI. This engine was produced by MAN, and although it was intended for use in a battleship all along, it was scrapped at the end of WWI under the Versailles Treaty. Its designs and the original designers, however, were still at MAN, and they updated the new design with modern technology like direct fuel injection, and doubled the banks to create a 30,000 HP V-12 marine diesel. Four of these were used for the light battleship, and five were in the main battleship.
Above: the WWI-era prototype maritime diesel used as the basis for battleship engines.
The torpedoes themselves were standard G7 torpedoes until a Japanese technology exchange brought the pure oxygen Type 93 24” torpedo to the attention of the Reichsmarine. A competing design was quickly developed by Hellmuth Walter using hydrogen peroxide, which was ultimately selected to replace the standard G7 torpedo in both 24” ship-launched and 21” submarine-launched versions.
The submarines themselves went through the standard design process of the Type VII and Type IX families, followed by the Type XX submarine (the real life Type XXI submarine), which however was fully developed and in service by 1942. This was due to early patronage and support of Hellmuth Walter's air-independent propulsion concept, which resulted in the earlier development of a Type XVII equivalent, and an earlier battery-powered development which became the Type XX. The other important addition was that of the snorkel, developed from Dutch designs in the 1930's and fully developed for installation on existing and new submarines by 1939.
When the Reichsmarine was experimenting with amphibious operations around 1938, several significant shortcomings were noted, notably the extreme difficulty associated with landing troops and equipment without significant risk to themselves or their transports. Fortunately, the Japanese already had plenty of experience in amphibious warfare in China, and had developed several new warship designs to land troops quickly and effectively in the face of enemy resistance. The most obvious of these were the Daihatsu-class landing craft with its good seakeeping and bow ramp, and its larger counterpart, the Toku Daihatsu-class landing craft, intended for vehicle cargo. In addition to this, they had developed a support boat with a small size and shallow draft for close range fire support during landing operations, known as the AB-Tei class support vessel. To carry all of this, a large amphibious assault vessel had been built. Known as the Shinshu Maru, the 8,000 ton vessel had a well deck for carrying and launching the landing craft and support vessels it carried, as well as a catapult for launching its complement of aircraft.
In addition to the specifications and designs for these ships, the Japanese gave access to 2 newer designs that they had been working on since 1937. Created as a response to perceived shortcomings in their landing craft during operations in China, the new designs were intended to land larger numbers of troops than the earlier designs. The first design, intended to succeed the Shinshu Maru, took that ship's well deck and added a full-length flight deck for aircraft to take off (but not land) from. The resultant 11,000 ton ship (the Akitsu Maru) resembled an aircraft carrier, but without a hangar, and a well deck for launching 29 landing craft and 4 support vessels, like its predecessor.
Above: the Akitsu Maru, the basis for similar German vessels. Note the crane blocking one end of the flight deck (rectified in German designs) and the closed well deck doors at the stern of the ship
The other new design, the SS-1, was intended to land heavy equipment, including tanks, directly onto the shore rapidly. It's 900 ton hull was based on the design of icebreakers so that it could beach itself, and open its bow doors to unload all of its heavy cargo straight onto beaches. While these 2 new designs were still in the development phase, their plans were made available to the Reichsmarine.
Above: the SS-1 landing ship, on which German designs were based. Note the bow doors for offloading cargo
With these designs, the navy expanded the marines, and set about adapting the newest Japanese designs for their uses. This would result in adopting variants of the Daihatsu, the Toku Daihatsu, the AB-Tei, the SS-1, and the Akitsu Maru-class warships. The small landing craft and the SS-1 landing ship were largely unchanged, save for switching to welded construction and diesel propulsion (standard for all ships by this point), and the only major change to the AB-Tei class was to swap the turret for one based on that of the Panzer I. However, the large 11,000 ton amphibious assault ship was virtually redesigned, adopting a hangar deck beneath the flight deck to store aircraft and an arrestor hook to recover as well as launch small aircraft like the Fi 156 or Bf 109 (no bombers though). It still retained a well deck that could carry and launch 30 Daihatsu equivalents, 5 Toku Daihatsu equivalents, and 4 AB-Tei equivalents. It additionally carried a regiment of marines and their equipment ready to deploy.
EDIT 6/26/16: shortened the length of the intermodal container from 9 m to 7.5 m (9m is way too long even for a semi-trailer), added the half-length container, added the 15 cm land-based flak, and cleaned up some of the grammar.
2nd EDIT 6/27/16: Added the heavy Opel Blitz 6x4 variant, changed the tractor trailer variant into a separate vehicle, gave the Opel Blitz a new diesel engine and primitive 4-wheel drive, and increased the weight of the naval 15 cm triple turret from 80 to 100 tons.
3rd EDIT 6/27/16: Changed Faustpatrone service entry date from 1936 to 1942, the Panzerfaust 150 service entry date from 1942 to 1944, and the Panzerfaust 250 service entry date from 1944 to 1945
4th EDIT 6/29/16: Major edit. Added section on railroad repair, changed the SK C/30 from being replaced by the 3.7 cm Flak C/30 to being cancelled in favor of it before entering service, added submarine snorkel, added section about adopting Japanese amphibious warfare vessels, added sections on mortars, grenade launchers, grenades, added leFH 18/40 instead of just GebH 40, and added sections on light automatic flak
5th EDIT 6/30/16: Changed photos of 2 cm flak from Solothurn S5-100 to Solothurn S-18/1100. Added references to Solothurn photos
6th EDIT 7/2/16: Major edit. Added Luftwaffe section, added designation for the 5 cm mortar prototype and Eierhandgranate
7th EDIT 7/2/16: Added appendixes and Do-335 to supplement the Ju 288 in the 1943 era Luftwaffe aircraft.
8th EDIT 7/8/16: Added section on subcaliber rounds for the sFH 40.
Sources:
http://www.aviarmor.net/tww2/tanks/germany/leichtetraktor.htm - the leichttraktor complete history
http://en.valka.cz/topic/view/66995/15-cm-sFH-40 - the heavy howitzer sFH 40
http://www.gwpda.org/naval/proppl.htm - the history of diesel propulsion in the German navy up until WWI
http://www.practicalmachinist.com/v...esel-engines-battleships-99-years-ago-162819/ - the diesel engines used as a basis for the battleship propulsion
https://weaponsandwarfare.com/15-cm-flak-50-55-60-60f/ - the 15 cm flak gun prototypes
http://en.valka.cz/topic/view/38878/15-cm-Gerat-50 -more information on 15 cm flak guns
https://www.flickr.com/photos/massimofoti/sets/72157624866330321/with/5005902994/ - photos of with Solothurn S-18/1100 in AA mount in Swiss museum
http://forum.axishistory.com/viewtopic.php?t=136241&start=15 - more photos and info on Solothurn S-18/1100
Appendix
my more in-depth posts on this thread that go into context about some part of the main post
Appendix 1: Fixing the state of the German rail network and rolling stock:
It seems that coal is still a good basis for the modernized railway, perhaps with main lines being electrified for supplementary high-speed trains and heavy usage (it's more efficient to burn coal in a power plant and send pure electricity to the train than it is to transport the coal to the train and burn it there). Still, I wasn't aware of how bad the entire German rail system was at that point. Not only was only a tiny fraction of the rail network up to the new standards requiring a 20 ton axle load, but most of the rolling stock was non-standardized WWI-era (if not earlier) locomotives and wagons. These conditions persisted right up through WWII. Since the modern, standardized Einheitsdampflokomotiven (German for Standard Steam Locomotives) constituted only 1/25 of the rolling stock in 1934 (1,000 out of ~25,000), and even with the simplified Kriegslokomotiven and a massive effort reached barely 1/3 of the rolling stock by the end of WWII (14,500 out of ~45,000), it's safe to say that even if production was ramped up, the production capacity won't be enough. Overall, while I think the Einheitsdampflokomotiven and the the similar electric trains were good designs (I can't think of many improvements to them- they're already standardized and efficient), there isn't enough production capacity to build them or lay new standardized track (with 20 ton max axle load). The German locomotive fleet stood at around 25,000 in 1934, and even at the end of WWII its increase to 45,000 locomotives, it was likely woefully inadequate. I suspect that ultimately the German wartime rail network would ideally be using over 60,000 locomotives, a number that could not be attained with existing infrastructure.
To solve this problem, I think the best solution would be to take advantage of mass production techniques and construct an unprecedented (for the time) new locomotive works somewhere in Germany, capable of mass-producing (using the most modern techniques) at least 1,000 Einheitsdampflokomotiven per month. To put this into perspective, only a handful of German locomotive works (perhaps a half-dozen) made this many Einheitsdampflokomotiven (including Kriegslokomotiven) in the entirety of the period from 1933 to 1945. This would be much like the equivalent of the Tesla Gigafactory for the locomotive world at the time. It would be able to replace the entirety of Germany's outdated non-standardized stock within 2 years, and fulfill Germany's wartime rolling stock requirements within 5 years. It would be immensely expensive, and very vulnerable to air attack (so it would likely have to have its own flak towers defending it, along with fighters), but it's the only method I see that can fix Germany's rolling stock problems in a reasonable period of time. Also, less impressive but no less important, is the requirement to start a new program to upgrade and repair as many of the German rail lines to the new standard as possible, preferably using machine labor wherever possible to save time, manpower, and cost.
With the locomotive manufacturing taken care of by the new works, the existing locomotive works can set to work replacing the older non-locomotive rolling stock, replacing boxcars with container wagons in the process.
Appendix 2: Japanese amphibious assault technology pre-Guadalcanal campaign
As for the landing craft, I found surprisingly advanced equipment that could be adopted from the Japanese at this time. Their amphibious equipment was far more advanced than I expect even the best case Germany could develop during this time, so in this TL they would base their designs off Japanese ones.
The landing craft would be the Daihatsu-class, famous as the inspiration for the LCVP "Higgins Boats." However, the Japanese also produced several other advanced designs. One of these was simply a larger Daihatsu, named the Toku Daihatsu-class. These were scaled up so that they could carry a medium tank (about 16 tons for Japanese designs) or heavier cargo. Of course, both designs were superior in many ways to their US counterparts. They had twin skegs beneath the hull for stability, they had markedly better seakeeping, they had diesel propulsion, and had steel construction so they were much tougher than the Higgins.
Above: US wartime identification manual on the Daihatsu and Toku Daihatsu-class landing craft
In addition to this, the AB-Tei class support vessel displaced 30 tons, carried 2 machine gun turrets and a 57 mm-armed tank turret, and were intended to provide close-in fire support during landing operations. While they saw more use as river gunboats, they performed their intended role well during amphibious assaults.
Above: 2 AB-Tei class support vessels
The larger vessels were even more modern, with the Shinshu Maru being the world's first amphibious assault ship. She looked like, and had all the features of, a modern Amphibious Transport Dock, including a well deck with storage for 29 Daihatsu-class landing craft, 25 smaller Shohatsu-class landing craft (which were being replaced by the Daihatsu-class anyway), 4 AB-Tei class support vessels, and a catapult with a complement of 29 aircraft. However, the aircraft were expected to land on captured airfields; there were no landing provisions on the ship.
Above: the Shinshu Maru and her well deck in the process of launching a landing craft (presumably during the Second Sino-Japanese War)
Her successor was the Akitsu Maru, which entered service in 1942 (though she was designed since 1937), and had a full length flight deck for autogyros in addition to the well deck of the Shinshu Maru, making her resemble an aircraft carrier, or modern Wasp-class Amphibious Assault Ship. This ship carried autogyros that could return to the ship, but lacked arrestor wires for landing proper aircraft. Still, this qualifies the Akitsu Maru as the world's first Landing Helicopter Dock. Later ships had similar features, but were converted from existing merchant ships, and entered service late in the war.
For Tank Landing Ships, a design was developed following experience in amphibious operations in China. This design was known as the SS-1 class amphibious assault ships, and it featured a bow door for unloading a lot of heavy cargo quickly. The ship resembled a US Landing Ship Tank, but was somewhat smaller. Still, after the Guadalcanal Campaign, the project, which was given low priority up until then, was cancelled in favor of a design based on an enlarged US Landing Ship Tank (the No. 101 class). Still, all of these designs would be available to Germany, should they wish to base their own designs on them (which they will in this TL).
Sources:
http://forums.ubi.com/showthread.ph...(like-me))?s=64347046df05f6dd38205bb67abc8a14 - information on Japanese small landing craft
http://pwencycl.kgbudge.com/D/a/Daihatsu_class.htm - information on the Daihatsu-class landing craft
http://pwencycl.kgbudge.com/T/o/Toku_Daihatsu_class.htm - information on the Toku Daihatsu-class landing craft
http://pwencycl.kgbudge.com/S/s/SS-1_class.htm - information on the SS-1 class landing ships
http://www.navypedia.org/ships/japan/jap_aux_ss.htm - more information on the SS-1 class landing ships
http://pwencycl.kgbudge.com/A/b/AB-Tei_class.htm - information on the AB-Tei class support ships
http://www.combinedfleet.com/Shinshu_t.htm - information on the Shinshu Maru
http://pwencycl.kgbudge.com/S/h/Shinshu_Maru_class.htm - more information on the Shinshu Maru
http://www.combinedfleet.com/Akitsu_t.htm - information on the Akitsu Maru
http://pwencycl.kgbudge.com/A/k/Akitsu_Maru_class.htm - more information on the Akitsu Maru
http://www.combinedfleet.com/Hatsudotei_c.htm - list of major Japanese amphibious vessels of WWII
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