The Battle of Fort Ében-Émael was a battle between Belgian and German forces that took place between 10 May and 11 May 1940, and was part of the Battle of Belgium and Fall Gelb, the German invasion of the Low Countries and France. An assault force of German paratroopers, Fallschirmjäger, was tasked with assaulting and capturing Fort Ében-Émael, a Belgian fortress whose strategic position and strong artillery emplacements dominated several important bridges over the Albert Canal. These carried roads which led into the Belgian heartland and were what the Wehrmacht intended to use to advance. As some of the German airborne forces assaulted the fortress and disabled the garrison and the artillery pieces inside it, others simultaneously captured two bridges over the canal.
Having disabled the fortress, the airborne troops were then ordered to protect the bridges against Belgian counter-attacks until they linked up with ground forces from the German 18th Army.
The battle was a strategic victory for the Wehrmacht, with the airborne troops landing on top of the fortress with gliders and using explosives and flamethrowers to disable the outer defences of the fortress. The Fallschirmjäger then entered the fortress, killing some defenders and containing the rest in the lower sections of the fortress. Simultaneously, the rest of the German assault force had landed near the three bridges over the canal, destroyed several pillboxes and defensive positions and defeated the Belgian forces guarding the bridges, capturing them and bringing them under German control. The airborne troops suffered heavy casualties during the operation, but succeeded in holding the bridges until the arrival of German ground forces. German forces were then able to use two bridges over the canal (one near Riemst and one near Veldwezelt) to bypass Belgian defensive positions and advance into Belgium to invade it. The bridge at Kanne was destroyed; Wehrmacht engineers constructed a temporary bridge.
Background
On 10 May 1940, Germany launched Fall Gelb ("Plan Yellow"), the invasion of the Low Countries and France. By attacking through the Netherlands, Luxembourg, and Belgium, the German Oberkommando der Wehrmacht planned to outflank the Maginot Line, and advance through southern Belgium and into northern France, cutting off the British Expeditionary Force and a large part of the French forces and forcing the French government to surrender. To gain access to northern France, German forces would have to defeat the armed forces of the Low Countries and either bypass or neutralize several defensive positions, primarily in Belgium and the Netherlands. Some of these defensive positions were only lightly defended and intended more as delaying positions than true defensive lines designed to stop an enemy attack.
Some defences were of a more permanent nature, possessed considerable fortifications and were garrisoned by significant numbers of troops. The Grebbe Line and the Peel Line in the Netherlands, which stretched from the southern shore of the Zuiderzee to the Belgian border near Weert, had many fortifications combined with natural obstacles, such as marsh-lands and the Geld Valley, which could easily be flooded to impede an attack. The main Belgian defensive line, the K-W Line (also known as the Dyle or Dijle Line), along the river Dyle, protected the port of Antwerp and the Belgian capital, Brussels. Between the K-W Line and the border was a delaying line along the Albert Canal. This delaying line was protected by forward positions manned by troops, except in a single area where the canal ran close to the Dutch border, which was known as the "Maastricht Appendix" due to the proximity of the Dutch city of Maastricht. There the Belgian military could not build forward positions due to the proximity of the border, and instead assigned an infantry division to guard the three bridges over the canal in the area, a brigade being assigned to each bridge. The bridges were defended by blockhouses equipped with machine-guns. Artillery support was provided by Fort Ében-Émael, whose artillery pieces covered two of the bridges.
The German High Command became aware of the defensive plan, which called for Belgian forces to briefly hold the delaying positions along the Albert Canal and then retreat to link up with British and French forces on the K-W Line. The Germans developed a strategy that would disrupt this plan, by seizing the three bridges in the "Maastricht Appendix", as well as other bridges in Belgium and the Netherlands. This would allow their Wehrmacht forces to breach the defensive positions and advance into the Netherlands.
Prelude
Belgian preparations
The Belgian 7th Infantry Division was assigned to guard the three bridges over the canal, supplementing the troops who garrisoned Fort Ében-Émael at the time of the battle. The defences for each bridge consisted of four large concrete pillboxes on the western side of the canal, three equipped with machine-guns and a fourth with an anti-tank gun; the bunker containing the anti-tank gun was positioned close to the road leading from the bridge, with one machinegun-equipped bunker immediately behind the bridge and two others flanking the bridge a short distance either side. A company position existed on the western bank of the canal by each of the bridges, with a small observation post on the eastern side, which could be quickly recalled, and all three bridges could be destroyed with demolition charges set into their structures, triggered by a firing mechanism situated in the anti-tank bunkers.
Fort Ében-Émael, which measured , had been built between 1932 and 1935, by digging the required space out of marl. It possessed walls and roofs composed of thick reinforced concrete, as well as four retractable casemates and sixty-four strongpoints. The fort was equipped with two 120mm artillery pieces with a range of ten miles which could traverse 360 degrees; sixteen 75mm artillery pieces; twelve 60mm high-velocity anti-tank guns; twenty-five twin-mounted machine-guns; and four anti-aircraft guns. One side of the fort faced the canal, whilst the other three faced land and were defended by minefields; deep ditches; a high wall; concrete pillboxes fitted with machine-guns; fifteen searchlights were emplaced across the fort; and 60mm anti-tank guns. Many tunnels ran beneath the fort, connecting individual bunkers to the command centre and the ammunition stores. The fort also possessed its own hospital and living quarters for the garrison, as well as a power station that provided electricity to power the guns, provide internal and external illumination, and to power the wireless network and air-purifying system used by the garrison.
Belgian plans did not call for the garrison of the fort and the attached defending forces to fight a sustained battle against an attacking force; it was assumed that sufficient warning of an attack would be given so that the detachment on the eastern side of the canal could be withdrawn, the bridges destroyed and the garrison ready to fight a delaying action. The defending force would then retire to the main defensive positions along the river Dyle, where they would link up with other Allied forces.
German preparations The airborne assault on Fort Ében-Émael, and the three bridges it helped protect, was part of a much larger German airborne operation that involved the 7th Air Division and the 22nd Airlanding Division. The 7th Air Division, comprising three parachute regiments and one infantry regiment, was tasked with capturing river and canal bridges that led to the Royal Netherlands Army defensive positions centred around Rotterdam, as well as an airfield at Waalhaven. The 22nd Airlanding Division, which was composed of two infantry regiments and a reinforced parachute battalion, was tasked with capturing airfields in the vicinity of The Hague at Valkenburg, Ockenburg and Ypenburg. Once these airfields had been secured by the parachute battalion, the rest of the division would land with the aim of occupying the Dutch capital of Amsterdam and capturing the entire Dutch government, the Dutch royal family, and high-ranking members of the Netherlands Armed Forces. The division would also interdict all roads and railway lines in the area to impede the movement of Dutch forces. The intention of the German OKW was to use the two airborne divisions to create a corridor, along which the 18th Army could advance into the Netherlands without being impeded by destroyed bridges. General Kurt Student, who proposed the deployment of the two airborne divisions, argued that their presence would hold open the southern approaches to Rotterdam, prevent the movement of Dutch reserves based in north-west Holland and any French Army forces sent to aid the Dutch defenders, and deny the use of airfields to Allied aircraft, all of which would aid a rapid advance by the 18th Army. 400 Junkers Ju 52 transport aircraft would be used to deploy the parachute elements of the airborne troops, as well as transport the elements of the two airborne divisions not landing by parachute or glider.
The force tasked with assaulting the fort and capturing the three bridges was formed from elements of the 7th Air Division and the 22nd Airlanding Division, and was named Sturmabteilung Koch (Assault Detachment Koch) after the leader of the force, Hauptmann Walter Koch. The force, which had been assembled in November 1939, was primarily composed of parachutists from the 1st Parachute Regiment and engineers from the 7th Air Division, as well as a small group of Luftwaffe pilots. Although the force was composed primarily of parachutists, it was decided that the first landings by the force should be by glider. Adolf Hitler, who had taken a personal interest in the arrangements for the assault force, had ordered that gliders be used after being told by his personal pilot, Hanna Reitsch, that gliders in flight were nearly silent; it was believed that, since Belgian anti-aircraft defences used sound-location arrays and not radar, it would be possible to tow gliders near to the Dutch border and then release them, achieving a surprise attack as the Belgian defenders would not be able to detect them. Fifty DFS 230 transport gliders were supplied for use by the assault force, and then a period of intensive training began. A detailed study of the fort, the bridges and the local area was made, and a replica of the area was constructed for the airborne troops to train in. Joint exercises between the parachutists and the glider pilots were carried out in early 1940, and refinements were made to the equipment and tactics to be used, such as barbed wire being added to the nose-skids of the gliders to reduce their landing run, and the airborne troops trained with flamethrowers and specialized shaped charge explosives, the latter of which were so secret that they were only used on fortifications in Gleiwitz, Germany and not on fortifications in Czechoslovakia similar to Fort Ében-Émael. Secrecy was also maintained in other ways. When exercises were completed gliders and equipment would be broken down and taken away in furniture vans, the sub-units of the force were frequently renamed and moved from one location to another, unit badges and insignia were removed, and the airborne troops were not permitted to leave their barracks or to take leave.