Both sides of the Iron Curtain developed detailed battle plans in regards to war in Europe should the Cold War have gone hot. Allied military planners had begun studying the terrain and anticipating Soviet military operations in Europe since the end of the Second World War. NATO military planners theorized that the Soviets and their Warsaw Pact allies would attack from one of three areas across the middle of Europe and divided Germany.
The first expected theory of Soviet invasion was centered on the area of the North German Plain. The composition and terrain of the North German Plain makes it ideally suitable for the deployment and maneuvering of armored and mechanized formations. The North German Plain was for the most part in the British areas of West Germany and in the event of war in Germany, the Warsaw Pact invasion led by elements of the Soviet 3rd Shock Army and the 8th Guards Army of the Group of Soviet Forces Germany, would be countered by elements of NATO's Northern Army Group and Second Allied Tactical Air Force comprised of West German, Dutch, Belgian, British and American combat forces.
The second suspected route of attack was identified by allied planners as the Fulda Gap, a corridor of lowlands between the East German border and the city of Frankfurt am Main in West Germany. The Fulda Gap would be less suitable for armored and mechanized maneuvering than the North German Plain but it presented the Warsaw Pact with a direct route of attack on the heart of the United States military in West Germany and the financial heart of the Federal Republic: Frankfurt am Main. By attacking through the Fulda Gap, Warsaw Pact forces could attempt to seize control of two large airfields one being the Rhein Main Airbase and effectively cut off American reinforcements to the theater. In using the Fulda Gap, upon western exit of the Gap armored forces would encounter favorable terrain which extended to the banks of the Rhine River which increased Soviet chances of reaching and crossing the Rhine before NATO forces could arrive and prevent the advance.
The third and least likely of the suspected routes of invasion was identifed as being through the Danube River Valley.
Due to its proximity to West Germany, the German Democratic Republic was expected to play a major role in the assault on western Europe. Elements of the Nationale Volksarmee trained constantly in cooperation with its Soviet and Warsaw Pact allies to perfect interoperability in the event of war with NATO. The East German Army would play a major role in the initial phases of the invasion of West Germany and principle to the opening phases would be the employment of shock troops to disrupt Allied concentrations and clear the way for heavier elements to reach their assigned objectives. In this manner East Germany would turn to its elite 500 man assault unit, the 40. Fallschirmjägerbataillon Willi Sänger. An airborne infantry regiment trained in dissimilar warfare and commando tactics, the unit was expected to infiltrate and sabotage NATO command structures and disrupt supply routes as well as neutralize nuclear weapons launchers, enemy command and control facilities, prevent the resupply and reinforcement of NATO forces and occupy areas of strategic importance until friendly Warsaw Pact forces could arrive.
Specialized in fighting in NATO's rear areas, each soldier was trained to be an independent thinker and received specialized training in areas that included day/night time combat, day/night parachute jumping, handling explosives and incendiary devices, mountain climbing, skiing, swimming, diving, close combat and hand to hand combat training, radio communications and deception, urban combat, advanced marksmanship, reconnaissance, surveillance, survival and training in foreign languages. Everything in the unit was designed to be readily transportable by Luftstreitkräfte transport planes or helicopter to the target area. In combat, the companies of the battalion would be organized into five or six man teams to reduce its operational profile in the theater.
By the end of the 1960s, the East German military command had developed a plan for the initial stages of armed conflict with the West that would come to be known as Operation DUNAJ or Operation Danube. According to the East German battle plan coordinated with Warsaw Pact commands, elements of the 40. Fallschirmjägerbataillon Willi Sänger unit would initiate attacks on West Germany commencing with intial landings in a two pronged assault from southern East Germany into southern West Germany effectively the American zone near Bamberg and Würzburg. Antonov An-2 Colts and Antonov An-26 Curl transports or Mil Mi-8 Hip utility helicopters of the Luftstreitkräfte der NVA would presumably penetrate West German airspace under the cover of darkness and drop the groups of paratroopers into the rear areas of NATO forces. Simultaneously a second wave would be launched from the Czechoslovak Socialist Republic into West Germany bypassing Regensburg. These landings would be followed up by NVA armored and mechanized assaults of the 7. Panzerdivision '7th Armored Division' from Dresden, 11. Motorisierte-Schützen Division '11th Motorized Rifles Division' from Halle and 4. Motorisierte-Schützen Division '4th Motorized Rifles Division' from Erfurt in five thrusts into the American and British sectors. Formations of Landstreitkräfte T-72 and T-62 main battle tanks along with BMP armored personnel carriers, BRDM armored personnel carriers and other armored vehicles along with Warsaw Pact allied armor would then push to penetrate into the French sector.
The northern most elements of ground forces consisting of 9. Panzerdivision '9th Armored Division' from Eggesin, 8. Motorisierte-Schützen Division '8th Motorized Rifles Division' from Schwerin and 1. Motorisierte-Schützen Division '1st Motorized Rifles Division' from Potsdam would roll across the Iinner German Border and would thus cross the North German Plain making a push through Hannover and Bielefeld to defeat and capture the British Army of the Rhine headquarters before heading for Dortmund. Other elements of this assault force would also begin heading towards Siegen. The middle, central prongs of the attack would push through the Fulda Gap moving to defeat the American headquarters at Frankfurt am Main along the Main River and Mannheim. The fifth and southern most prong of the attack would be aimed towards the town of Ulm. Once secured, a secondary airborne assault would be launched with the aims of pushing through the Saarland and invading France. Airborne assault forces would bypass Metz and Strassburg and make landings near Verdun and Langres.
The battle plan was revised and updated several times throughout the course of the Cold War, and would remain and effective battle plan up until the collapse of the German Democratic Republic in 1990.