Yet even if Heeresgruppe Mitte had retained the LVI Panzerkorps and been reinforced with additional armour, Germany’s ability to conduct mobile operations was rapidly coming to an end due to the fuel crisis. The Third Reich had always been short of fuel, but the Allied bombing effort that began in April 1944 against German oil production facilities had an almost immediate impact upon the Luftwaffe and mechanized units. The Romanian oil fields at Ploesti were bombed repeatedly in April-June 1944 and production was curtailed by 80 per cent, while the attacks on synthetic plants deprived Germany of both fuel and synthetic rubber. Between March and September 1944, Germany’s production of fuel for motor vehicles fell by 64 per cent, which immediately impacted the operational mobility of Panzer-Divisionen at the front.{40}
On 31 May 1944, the Ostheer had been reduced to only 955 operational tanks on the Eastern Front, of which 233 were Tigers, 238 were Panthers and 484 were Pz IVs.{41} The Ostheer had a total of 16 Panzer-Divisionen, seven Panzergrenadier-Divisionen and six schwere Panzer-Abteilungen. Only about six of the 23 mechanized divisions were still reasonably combat effective (Großdeutschland, 1., 4., 5., 8. and 24.Panzer-Divisionen) while the rest were reduced to 25–40 per cent combat effectiveness. Noticeably, the bulk of the German armour was in the south: 606 tanks in Heeresgruppe Nordukraine, 190 in Südukraine, 86 in Mitte and just 73 in Nord. In contrast, the Red Army was now capable of committing over 6,000 tanks into battle across the Eastern Front, with large reserves ready to replace losses.
By early June 1944, Heeresgruppe Mitte had over 578,000 personnel assigned – 31 per cent of the entire Ostheer – although its actual front-line combat strength was barely 120,000 troops.{42} Busch’s main forces consisted of Generaloberst Georg-Hans Reinhardt’s PzAOK 3, General der Infanterie Kurt von Tippelskirch’s AOK 4 and General der Infanterie Hans Jordan’s AOK 9, which altogether had a total of 26 infantry divisions, two Luftwaffe Feld-Divisionen and three Panzergrenadier-Divisionen (18, 25, Feldherrnhalle). Busch also had Generaloberst Walter Weiss’s AOK 2, which protected the boundary between Heeresgruppe Mitte and Heeresgruppe Nordukraine. Busch was fairly optimistic that the salient could be held due to the strong field works, since previous Soviet offensives had taken days or weeks to chew their way through less robust defences. Based upon past experience of Soviet efforts to break German defence lines, neither Busch nor the OKH anticipated that the Red Army would be able to create a breakthrough in more than one or two sectors, which could then be contained. The only really worrisome factor was the weakness of the Luftwaffe, since Luftflotte 6 only had 40 Bf-109G fighters assigned – grossly insufficient for air cover over Heeresgruppe Mitte.
Since Busch’s mission was strictly defensive, most of the armour assigned to Heeresgruppe Mitte consisted of assault guns and self-propelled Panzerjägers. Aside from Mortimer’s 20.Panzer-Division, the only other division with tanks was Feldherrnhalle, which had 20 Pz IVs and a battery of StuG-IIIs. Altogether, the PzAOK 3 had about 60 assault guns and one battalion of Nashorns (s.Pz. Jgr.Abt.59), the AOK 4 had 246 assault guns and two battalions of Nashorns (s.Pz.Jgr.Abt.655) and AOK 9 had 76 assault guns. This gave Heeresgruppe Mitte a grand total of 111 tanks, 382 assault guns and 100–120 tank destroyers (Nashorn and Marder).{43} It is significant that Heeresgruppe Mitte had no Panthers at this point – one year after they had been introduced on the Eastern Front – and still relied upon the Pz IV as its main battle tank. Although German industry had increased the production of the Pz IV tank to 300 per month, the latest Ausf J version was a step backward, since it omitted the turret motor to save space and weight; this meant that German tankers using this model now had to laboriously crank the turret around by hand – a huge disadvantage in battle. Busch could have massed his assault guns in mobile anti-tank reserves with 50 or more StuG-IIIs kept behind each army, but he allowed these assets to be split up into penny packets, generally a battery or a platoon assigned to each infantry division.
German intelligence expected that any new Soviet offensives against Heeresgruppe Mitte would likely focus on Vitebsk and Orsha, as they had in the past. However, since the OKH expected the main Soviet offensive would be against Model’s Heeresgruppe Nordukraine that is where the bulk of the German armour was deployed. Thus Busch’s army group was now like the French in 1940, expecting a predictable battle of position but getting a battle of manoeuvre for which it was unprepared.
On the other side, the Soviets had four fronts deployed against Heeresgruppe Mitte: Rokossovsky’s 1st Byelorussian Front, General-polkovnik Georgy F. Zakharov’s 2nd Byelorussian Front, General-polkovnik Ivan Chernyakhovsky’s 3rd Byelorussian Front and General Ivan Bagramyan’s 1st Baltic Front. After the liberation of the Ukraine, Stalin was eager to see Byelorussia liberated as well and he directed the Stavka to begin planning for a major summer offensive against Heeresgruppe Mitte. Zhukov was recalled to Moscow in late April and together with Vasilevsky and other members of the Stavka, they developed an outline for a grand offensive to be known as Bagration. Unlike previous Soviet offensives, Bagration was intended to be a massive set-piece battle with the resources needed to achieve a decisive victory. This time, Stalin did not rush the professionals but allowed Zhukov and Vasilevsky the time they need to amass overwhelming combat power against Heeresgruppe Mitte. While most of the 118 rifle divisions allocated for the operation were at only 60 per cent of authorized strength, the Soviets would still enjoy a 3–1 superiority in infantry. This time, the Red Army would use all the tools of combined arms warfare in synchronization, in order to unlock the German defences. A massive amount of artillery support, including 13 artillery divisions, was provided for Bagration. Four air armies were deployed with over 5,000 aircraft, including 2,300 fighters – which would allow the VVS to completely dominate the airspace over the battlefield.
The Stavka intended to use infantry, artillery and airpower to smash through Heeresgruppe Mitte’s front lines at multiple points, and then push its armour through to exploit deep into the rear. Zhukov and Vasilevsky were both familiar with Vladimir K. Triandafillov’s pre-war theories of Deep Battle (glubokiy boy) and intended to use a similar approach in the conduct of Bagration. As part of the Maskirovka (deception) effort, the bulk of the Red Army’s armoured formations remained with the 1st and 2nd Ukrainian Fronts, but the four fronts involved in Bagration were provided with six tank corps (1 TC, 1 GTC, 2 GTC, 3 GTC, 9 TC, 29 TC) and two mechanized corps (1 MC, 3 GMC), including Rotmistrov’s 5 GTA which was quietly transferred from northern Romania to Chernyakhovsky’s 3rd Byelorussian Front. These armoured formations had over 2,700 tanks. Soviet production was such that the Red Army could now begin to equip tank brigades entirely with T-34s and the T-70 light tanks began to phase out of service. About 20 per cent of the T-34s were the newest T-34/85 model, which was definitely superior to the Pz IV Ausf J. Some Soviet units were still equipped primarily with Lend-Lease armour, such as the 3 GMC, which had over 100 M4A2 Shermans and some Valentines and Churchills.{44} The number of JS-2 heavy tanks was still limited and only 80 in four regiments were available for Bagration. However, production of the Su-76M self-propelled gun was well advanced and over 1,000 SPGs would be involved in the offensive, as well as over 100 of the new JSU-122 which was capable of defeating Tiger tanks.