Spec Ops: Case Studies in Special Operations Warfare: Theory and Practice - William H. McRaven (1996)

Chapter 2. The German Attack on Eben Emael, 10 May 1940


In January 1933, Adolf Hitler was appointed chancellor of Germany. His rise to power was fueled by his promise to avenge the defeat of World War I and the humiliating Treaty of Versailles. By 1935 Hitler had completely rejected the Armistice of 1918, which limited German arms production. He began to build the most powerful army in Europe, and by the late 1930s there was little doubt the German army was preparing for war.

The small country of Belgium had long been considered a primary axis for a German invasion into France. Before World War I, the chief of the German General Staff, Count Alfred von Schlieffen, developed a plan calling for the encirclement of France by two avenues of approach, through the Swiss Alps and across Belgium. Little had changed during the interwar years to warrant a major modification to the Germans’ Schlieffen Plan. The French and Belgians were keenly aware of their geographical predicament. However, cutbacks after World War I significantly reduced the size and effectiveness of both armies and fostered a reliance on defensive warfare. This defensive mentality was manifested in France’s Mag-inot line and Belgium’s Albert Canal defenses.

The Maginot line was a system of fortifications built along the eastern French border in the 1930s. It extended from Switzerland to Belgium. The Belgians constructed a similar defensive perimeter along the Albert Canal. The linchpin of their fortifications was the largest single fort of its day, Eben Emael. Between the Albert Canal and the Maginot line stood the massive Ardennes Forest, a seemingly impregnable obstacle for an advancing army. With these fortifications in place the French and British positioned their armies in northern France to take advantage of the only logical German avenues of approach.

The German commander in chief, Gen. Walther von Brauchitsch, and his chief of staff, Gen. Franz Halder, both felt that a German advance must outflank the Maginot line and concentrate the Schwer-punkt (point of the spear) of the attack north of the impassable Ardennes Forest. This would take the bulk of the German army through Holland, then Belgium. A smaller but relatively strong force would attempt to negotiate the Ardennes and cross the Meuse River between Givet and Sedan in eastern France. Although this was the predictable approach, Brauchitsch and Halder were counting on surprise and the superior German forces to rout the enemy.

This plan met with exceptional criticism from two prominent German generals, Erich von Manstein (chief of staff, Army Group A) and Heinz Guderian (XIX Panzer Corps commander). Guderian proposed driving three panzer corps through the Ardennes, across the Meuse, and deep into the heart of France. This would allow the Germans to flank the Allied forces, who were expecting the main thrust to come across Belgium. “Before the attack could succeed,” wrote historian Charles Kirkpatrick, “the French mobile forces, along with their British allies, had to be decisively engaged in battle elsewhere, so that they could not swiftly intervene in the developing attack in the south. In essence the trick was to entice the British and French main body into advancing to give battle in Belgium, where German conventional infantry divisions stiffened by a few armored divisions would tie them down.”1

The Allies were not prepared to commit forces to the north unless the Germans violated Belgian neutrality, and then only if they were certain it was the main German assault. Hitler quickly accepted the Guderian Plan, realizing that its genius lay in the boldness and surprise with which German armor would be deployed.

Fig. 2–1. The Importance of Eben Emael in Relation to the Blitzkrieg. From Mrazek, Eben Emael, 20

Fig. 2–2. The Location of Eben Emael. From Mrazek, Eben Emael, 23

In order to ensure the Allies committed forces to the north, the Germans had to move swiftly through Holland and into Belgium. This required crossing the Albert Canal and moving two panzer corps through Belgium to engage the British Expeditionary Force and the French First Army. Before the Germans could get deep into Belgium they had to cross fifteen miles of Holland and the Albert Canal. The canal could only be crossed by three bridges at Veld-wezelt, Vroenhoven, and Canne. Although the entire campaign hinged on securing the bridges, the defenses surrounding them “were not considered to pose a problem. There were several dropping zones for parachutists [and gliders] close by from which assault parties could quickly overcome the Belgian army defences covering the crossings.”2 The real problem was Fort Eben Emael. Even if the bridges were captured by German paratroopers or glidermen, the guns at Eben Emael could still destroy them from afar and prevent the panzers from entering Belgium.

On 27 October 1939, Gen. Kurt Student, commander of the 7th Airborne Division, was summoned to the Reich Chancellery in Berlin by Adolf Hitler. Student had developed the concept of three-dimensional warfare in which airborne troops could be inserted behind the lines and, using surprise and speed, could attack the enemy where he was least prepared. Hitler viewed Student’s concept as a new secret weapon.3

Hitler outlined a concept to seize the fort at Eben Emael using gliders to land troops atop the earthen structure and destroy the guns protecting the canal bridges. He directed Student to review his plan and return the following day with an answer. Student was an accomplished glider pilot and had been conducting tests using troop-carrying gliders to insert his airborne personnel. The following day Student returned and told the führer that the mission was possible provided it was done at daybreak or morning twilight. Hitler accepted Student’s concept and ordered him to “take Fort Eben Emael!”


The small town of Eben Emael was located just inside the border separating Belgium and Holland. The fort, which takes its name from the town, was completed in 1935. It was situated on the Albert Canal adjacent to the Meuse River just three miles south of the city of Maastricht. At the site of the fort, the walls of the canal rose two hundred feet from the water level to the top of the ridge. From the top of the fort the defenders could see miles into the German countryside as well as the three bridges at Canne, Vroenhoven, and Veldwezelt.

The fort itself was roughly diamond shaped with the tip facing north, the east wall along the Albert Canal, and the west wall (fortified with a 450-yard-long antitank moat) bordered by the Geer River. The fort measured eleven hundred yards north to south by eight hundred yards at its widest point. On top were ten casemates, five operational cupolas, and two dummy cupolas. Along the wall of the canal were two additional casemates. The casemates and cupolas were similar in construction to the turrets of a battleship, with guns protruding from apertures in either a six-inch-thick steel dome or a concrete blockhouse. Each fighting position housed a crew of sixteen to thirty men depending on the size and number of guns. The main batteries at casemates 26, 18, and 12 each had three 75mm guns. These guns provided the primary protection for the outlying towns and the three canal bridges. Casement 9 and cupolas 23 and 31 housed twin 75mm guns. Cupola 24 contained twin 120mm guns, the largest at Eben Emael. These guns were capable of ranging twelve miles. The remaining casemates and cupolas housed twin 75mm guns and mitrailleuse machine guns which provided additional anti-infantry defense of the fortress. There were five 60mm antiaircraft batteries situated around casemate 30. The one defensive shortfall of Eben Emael was the lack of fighting trenches and mines on top of the fort. There were, however, five rows of barbed wire strung in strategic positions. Outside the surface of the fort there were rows and rows of barbed wire, steel hedgehogs, and minefields, but the grassy top lay vulnerable.

Below the surface there were three levels that provided support for the fort’s main mission as an artillery emplacement. The top level consisted of the machinery for operating the massive guns and the protective steel doors for preventing entry into the belly of the fort. The second level contained a small infirmary, ammunition storage, six 175-horsepower electric generators that provided all the fort’s power, a communications center, and the command post. The third level housed the barracks for the fort’s personnel. The entire complex was designed with the guns in mind. Ammunition hoists serviced the guns directly, stairs and elevators were constructed to allow ammo bearers ease of movement, and air-conditioning and heating units ensured that the troops enjoyed adequate living conditions throughout the year. The entire fort was crisscrossed with five miles of tunnels linking all major gun and support systems. The only exterior entrance into the fort lay on the southwest side, away from the canal.

Fig. 2–3 Casemates and Cupolas at Eben Emael and the Squads Assigned to Destroy Them. From Mrazek, Eben Emael, 80, redrawn with additional material at U.S. Navy Postgraduate School, Monterey, California

The troops that manned the guns rotated duty throughout the month. Off-duty personnel were confined to the area around the village of Eben Emael. If they were needed in an emergency an alarm would be sounded by firing twenty blank rounds every thirty seconds. On the day of the German attack, the fort had an authorized strength of twelve hundred officers and men. However, owing to leave, illness, or out-of-area training, the total complement of the fort included only 18 officers, 62 noncommissioned officers, and 570 enlisted. Additionally, there were 233 soldiers approximately four miles away at Wonck.


In 1935, the German High Command began training its first paratroopers and several months later established the first parachute battalion. In 1938, Luftwaffe Gen. Kurt Student was given command of the airborne forces and quickly began to develop a large-scale parachute capability within the German air force. Soon he had established the 7th Air Division and also received command of the 22d Airborne Division.* These forces included not only parachutists, but all air and ground support necessary to accomplish large-scale airborne operations.

After accepting Hitler’s order to seize Eben Emael and the nearby bridges, General Student assigned Capt. S. A. Koch and his 1st Company of Flieger-Jaeger Regiment 1 to conduct the mission. Koch began training his company for the mission on 2 November 1939, and it assumed the name Storm Detachment Koch. The detachment consisted of one company of parachutists (soon to receive the name glidermen), one platoon of parachute-qualified engineers (these men were eventually tasked with taking Eben Emael), a transport group of Ju 52 aircraft, and over forty gliders with pilots and ground crews.

From these forces Koch divided the detachment into four assault elements. The force assigned to assault Eben Emael was codenamed Granite and commanded by Lt. Rudolf Witzig. It consisted of two officers, eleven glider pilots, and seventy-two enlisted men. The element tasked with capturing the bridge at Vroenhoven was code-named Concrete and commanded by Lieutenant Schacht. It consisted of five officers including Captain Koch and a small command element, eleven gliders and pilots, and ninety-four enlisted men. The third element was codenamed Steel and was ordered to seize the bridge at Veldwezelt. Commanded by Lieutenant Altmann, it had only one officer, ten gliders and pilots, and eighty-nine enlisted. The last element was codenamed Iron and commanded by Lieutenant Schaechter. Schaechter had one more officer, nine gliders and pilots, and seventy-nine enlisted men. They were assigned to capture the bridge at Canne.

At the outset of the operation, General Student made every effort to conceal the existence of the detachment. “The whole premise behind the operation was that any leak in security could compromise the mission, and the only way for this mission to be successful was to achieve total surprise.”4 They trained at Hildesheim, near Hanover, and took the deceptive title of Experimental Section Friedrichshafen. As the detachment moved to other locations for training they were often renamed. Lieutenant Witzig’s engineer platoon once received the title Airport Construction Platoon. The soldiers were not allowed to send personal mail or make calls unless cleared through Koch. Sgt. Helmut Wenzel, the senior enlisted man in Witzig’s platoon, recalled, “We couldn’t go into bars, but we could go into movies. However, we had to have a guard. Usually by the time the movie was over, the guards had lost interest and gone home … Also we didn’t wear insignia, and we had other names. Once we ran into some girls we knew and the whole unit had to be transferred.”5

Each man was also required to sign the following statement:

I am aware that I shall risk sentence of death should I, by intent or carelessness, make known to another person by spoken word or illustration anything concerning the base at which I am serving.6

Witzig’s engineer platoon had served together for over a year before this mission was conceived. Almost all of the men participated in the Polish campaign but had only seen limited action. “They were honorable men,” Sergeant Wenzel recalled, “but they were all a little crazy.”7

When Witzig first reported to the platoon he was not well received. “They were undisciplined and I was not popular because I changed the standards.”8 Witzig kept his distance from the men. Occasionally he would have a beer with his soldiers, but he never let them get too close. “They never called me by my first name or used informal language.”9 Most of the men expected to be discharged upon return from Poland, but soon found out that their war was just beginning.

The key to a successful mission clearly lay in the ability of the Luftwaffe to deliver Witzig’s combat engineers to Eben Emael undetected. Since the early 1930s Germany had been preparing its youth for a future war on the European continent. A large part of this effort was devoted to encouraging the sport of gliding. All across Germany young men and women began learning to fly. This created a sizable pool of talented pilots, fostered competition, and improved the capabilities of existing gliders. In 1933, Dr. Alexander Lippisch developed a large glider capable of carrying heavy loads of meteorological equipment. Although the glider did not soar like the smaller sport gliders, it was able to maintain a gradual glide path from its release point. The Luftwaffe soon saw the military application for this glider and recruited the Deutsche Forschungsanstalt für Segelflug (DFS) aircraft company, which was associated with the Rhoen Research Institute, to build a prototype. By 1939 they had produced the DFS 230. This glider was to have a pivotal role in the operation.

The DFS 230 was approximately thirty-seven feet long, had a wing span of seventy-two feet, and was almost nine feet high at its maximum point. It was capable of being towed at 130 mph with a maximum glide speed of 180 mph. The glider weighed 1,896 pounds and could carry ten combat-loaded troops for a total loaded weight of 4,630 pounds. It was armed with a single flexible 7.95mm MG-15 and two fixed 7.92mm MG-34 machine guns.

Koch had been given a free hand in planning and training for Eben Emael, and it became readily apparent to him that the DFS 230, although an exceptionally capable glider, was difficult for novice glider pilots to fly. He recruited several internationally recognized glider pilots to assist in the training and execution of the mission. The more novice Luftwaffe glider pilots would be used to assault the bridges, where the approach was easier and the landing zone was larger. The seasoned sport pilots would take Witzig’s men to the top of Fort Eben Emael. Witzig, who does not dole out praise quickly, said emphatically, “These pilots were the best!”10

This infusion of experienced civilian pilots created quite a rift between the civilians and the novice Luftwaffe pilots. The civilians failed to conform to the usual military discipline and constantly berated the less experienced, rank-conscious Luftwaffe. This became a recurring problem for Koch and one that he never fully solved. The morale and esprit de corps evident in the glidermen and Luftwaffe were almost nonexistent in the civilian pilots. However, since the pilots would land with the glidermen, Koch integrated them into the assault element, insuring they participated in the planning and training.11


Rudolf Witzig was born on 14 August 1916, and at the age of twenty-three was placed in charge of the pioneer (engineer) platoon tasked with assaulting Eben Emael. He was young and inexperienced, and most of the platoon sergeants were older than he. Witzig was not well liked by the platoon. He was a strict disciplinarian, and the platoon members, even by Sergeant Wenzel’s account, were “bandits.” Although disciplined when they fought, they were undisciplined as a matter of routine.

The officer Witzig relieved had allowed the platoon to become lazy. Witzig set out to change that attitude. He was firm in his belief that an officer should be reasonable in his approach to his men. He should have “good nerves … be fit … be faithful … like women, but not be a whoremonger … [and above all] be totally convinced that the operation is necessary for the people and the unit.”12 Witzig believed in “meticulous planning and practice.”13When I interviewed him, Witzig remarked that the reason the Americans failed in Iran (referring to the Iranian hostage rescue attempt) was because the mission “wasn’t rehearsed enough.”14

Although Witzig is often described as a martinet, a rigid, military disciplinarian, he had the highest regard for his enlisted men. The Germans had very few officers by comparison with the Allies. Witzig commented that “attacks led by enlisted men would have been led by officers in other countries. This was allowed because our enlisted men were so good.”15 Witzig stressed that he gave individual squad leaders a great deal of responsibility and the freedom to develop their own plans.

Witzig was an officer with tremendous determination. During the initial journey to Eben Emael, Witzig’s glider crashed in Germany. He commandeered a vehicle, got the glider airborne, and arrived at the battle late. Referring to this incident, Wenzel remarked, “It was a testament to Witzig’s personality that he was able to get back to the fight.”16 This determination carried Witzig through the remainder of the war. The following year, on 21 May 1941, Witzig parachuted into Crete where, despite being outnumbered three to one, the Germans defeated the Allies and took the island. Although severely wounded there, Witzig recovered and in November 1942 fought in North Africa. In 1943, the 21st Parachute Engineer Regiment, formed under the command of Major Witzig, was sent to Russia and subsequently saw action at Kovno, Lithuania, and Vilna, Poland. In 1944, Witzig commanded the 18th Parachute Regiment and fought in France, Belgium, and Holland, eventually surrendering in April 1945.

After the war he transferred to the German army (the engineers were Luftwaffe) and rose to the rank of colonel, eventually becoming director of the engineer school in Munich. He retired from that assignment and still lives in Munich. His decorations include the Knights Cross with Oak Leaves.


On 3 November 1939, Captain Koch received orders for his company to make preparations to seize and hold the fort at Eben Emael and the three bridges at Vroenhoven, Veldwezelt, and Canne until German ground forces arrived. The basic plan had already been conceived by General Student and approved by Hitler. On order, the company would depart Cologne from airfields at Ostheim and Butzweilerhof. Separated into four groups (Iron, Granite, Concrete, Steel), they would be transported in gliders towed by Ju 52s to a release point approximately twenty kilometers from their objectives. At an altitude of approximately fifty-five hundred feet the gliders would be released and would proceed to their targets. Upon arrival at Eben Emael, Witzig’s engineer platoon would destroy the guns that covered the approaches to the three bridges and with the help of Stuka divebombers attempt to keep the Belgian defenders sealed inside until reinforcements arrived. As Witzig viewed the mission he had three objectives: “The first objective was to take out the machine guns on the surface so we could go in safely. The second objective was to take out the casemates, and the third [objective] was to survive!”17

The three bridges would be seized by Koch’s other elements, and the permanently emplaced explosive charges would be rendered inoperable.

In order to seize the fort, two phases of the operation had to be rehearsed in excruciating detail, the glider insertion and the actions at the objective. After managing to obtain the requisite number of glider pilots, Koch, with the help of world-class glider pilot Heiner Langer, set out to teach all the pilots the intricacies of the DFS 230. The pilots spent months learning to fly empty and then with a full load. All of the gear in the glider had to be tightly secured. The troops, who straddled a narrow center aisle bench, found that even the smallest unsecured item could become a hazard as the glider rode the shifting air currents. There was some debate as to whether Koch’s men actually conducted rehearsals in the gliders. Charles Kirkpatrick, writing for World War II magazine, noted that “neither [Koch nor Witzig] attached much importance to having their men actually fly in gliders and make landings in full scale rehearsals. Flying in gliders was inherently dangerous and could easily lead to training accidents that would diminish the force available for the mission.”18

This, however, is not the case. Both Witzig and Wenzel confirmed the fact that they rehearsed with the gliders. Witzig recalled, “We practiced most of the time in parts, but we did fly twice with the full equipment to ensure that everybody knew exactly how the landing would go and to overcome the fear of flying in the gliders; and to make sure everybody felt secure about the mission.”19

None of the pilots, even the experienced ones, had spent much time landing on unprepared runways. Initially it was found that the gliders required too much space to effectively land atop Eben Emael. Koch contacted DFS and they modified the DFS 230 with a hand brake that extended below the plywood frame and dug into the ground as the glider touched down. Hanna Reitsch, one of Germany’s most renowned aviatrixes, who had set the woman’s world record for sustained flight, was called upon to test the device. On her first attempt, she was almost knocked unconscious as the brake dug into the ground, causing the glider to come to a jarring stop. The device was later modified to allow the glider to stop quickly but not so abruptly as to be dangerous.

Most of the experienced civilian pilots were able to master the DFS 230 quickly, and they immediately transitioned to solo flying. However, the Luftwaffe pilots had the advantage of being qualified in both formation and night flying, things the civilians had never practiced. Formation or “daisy chain” flying required the gliders to be tied together and towed by a single aircraft. Eventually, however, the flight plan called for a one-to-one ratio of Ju 52s to DFS 230s. On D day the tow planes and gliders took off in sequence one after the other. “By March [1940] these glider pilots could take off into the night, maneuver into formation, and when cast off from the tow plane land on an unfamiliar field.”20

During most of the training, Storm Detachment Koch remained near Hildesheim or on the Czech border away from civilian or military observation. In January 1940 the gliders that were to be used on the mission were sent via enclosed truck to their departure airfields near Cologne. Several security measures were taken to conceal the arrival of the gliders and the nature of the training that was to continue in Cologne. A large cyclone fence was constructed around the glider hangars and straw mats were hung from the top to prevent people from seeing inside. Guards were posted and conducted twenty-four-hour-a-day patrols around the compound. On the day the gliders were to be taken from the trucks and reassembled, forty-five smoke generators were activated, creating a cloud over the entire airfield. “Local newspapers, commenting on the incident, passed it off as an engineer unit exercise designed to provide experience at setting off smoke screens destined to protect Dusseldorf in case of air raid.”21

As the glider training progressed, Koch worked with the assault elements to ensure they were fully prepared to conduct their ground missions. There were three objectives at Eben Emael that had to be neutralized in order for the fort to be rendered ineffective: the artillery that covered the bridges, the machine guns and antitank guns that protected the fort itself, and the antiaircraft guns that could engage the gliders and prevent the Stuka divebombers from properly supporting Witzig’s platoon. Witzig thought the intelligence on the fort was excellent. “We had flyover pictures, but of course at that time the detail wasn’t as good as today. But I had a picture and could tell where all the cupolas were, but I couldn’t see where the machine guns were on top of the casemates. I had to look at the casemates and cupolas and think, ‘Where would they put the machine guns?’ and I had to estimate where we needed to land and how to set up defensive positions.”22

These aerial photos helped determine that the steel cupolas atop the fort were essential for observing artillery fire. Destroying the cupolas would blind the observers and render the artillery fire ineffective. Additionally, the Luftwaffe obtained blueprints from a German subcontractor who had helped build the fort.23 This provided the assault elements with the exact location of the large guns and their fields of fire. A tabletop model of both the fort and the bridges was constructed. This small model was the only reconstruction used by the glidermen, but according to the model maker’s son, “The whole thing ended up in a rather super size ‘Sankastelmodell [sandbox model], built up in a school’s Gymnasium … Often paratroopers as well as pioneers came to do intensive practical ‘on the spot training’ … one even could walk on top respectively through the artificial landscape built up in this last large scale hall-model.”* Wherever this room-sized model ended up, neither Witzig nor Wenzel ever saw it.

Practical training began in a small way but quickly developed into detailed rehearsals. When they practiced at Hildesheim airfield, according to Witzig, “everything was laid out as things were at Eben Emael. We had markers set up with the exact distances between them. This way the pilots and crew leaders could orient themselves. I would go to each man and point out his objectives—‘This is yours, this is yours, and this is yours.’ ”24

Witzig sent some of his engineers to school during the workup period to improve their demolition skills and presumably their understanding of artillery and antiaircraft weapons systems. In February, the remainder of the men from Granite went to German Sudetenland to work against Czech casemates and cupolas. These defenses were similar to the fortifications at Eben Emael, but “more difficult.”25 The engineers and pilots practiced assaulting the casemates and using flamethrowers, bangalore torpedoes, light explosives, and their entire inventory of rifles, machine pistols, and pistols. Even the physical training revolved around the mission. Witzig recalled later, “It [physical training] was very demanding, and I tried not to concentrate on soccer and things like that, but on climbing with full gear and running with simulated charges. It was tactically oriented.”26

The one aspect of the training that was not fully rehearsed was the use of the new Hohlladung, or hollow (shaped), charge. Invented in 1888 by Charles Munroe, the shaped charge allows conventional explosives to create a jet of high pressure immediately upon detonation. This generates a tremendous penetrating capability and allows a relatively small amount of explosives to have a large effect on both steel and concrete. A 50-kilogram charge was capable of penetrating both the six-inch steel cupolas and the concrete reinforced casemates. The pressure created by the explosion would generally blow a one-foot hole in the objective and kill everyone inside. The shaped charges came in two sizes: a 50-kilogram charge in two pieces (each half came with a leather handle), which required assembly on the target (it could be done in seconds), and a 12.5-kilogram charge, which was used primarily against smaller targets.

Unfortunately, due to the sensitive nature of this new explosive (it was being used as a primer for Hitler’s atomic bomb), Witzig was the only man allowed to see the charge detonated before the mission. He was concerned about security. “They [the glidermen] didn’t need to know about the charge. They just needed to know exactly what their missions were and trust the charge. Most frogmen who attack ships with mines don’t know about [how strong] the charge is. They just know it will work.”27

By March the platoon had finalized the plan for destroying Eben Emael. Each squad, composed of seven or eight glidermen, had a primary objective and a secondary target in the event all eleven gliders failed to reach the fort. No detail was left to chance. From March to May the platoon continued to train. Several times during the training the detachment was put on alert. The clanging of the hangar bells would summon the glidermen to their positions, but in each case the order to stand down came soon after. By May 1940 Witzig’s men were more than ready and anxiously awaiting the moment to attack Eben Emael.


On 1 May 1940, Granite element, now under the cover name of No. 17 Reserve Squadron, was moved to the airfield at Ostheim, where final preparations were made for the assault.28 At no time during the training had any of Koch’s or Witzig’s men been told the name of the objective. “They knew that [they] were going to do an attack against a difficult target, but they didn’t know exactly where or when the attack would be.”29 Only the element leaders were privy to that information. On 9 May 1940 at 2130 the troops were assembled on the runway and the sealed orders were opened. The men were informed that the objective was a fort in the Belgian defense system. Departure time was 0325, 10 May. In the next few hours the ground crews began positioning the Ju 52s and the DFS 230s. There was one Ju 52 for each glider.

At approximately 0300 the glidermen loaded their planes and began taking off. Even with all the preparation the launches did not go well, but eventually all the gliders were airborne with the last glider, containing Witzig, in the air at 0335. The flight from Ostheim to Eben Emael took exactly fifty minutes as the gliders began to rise to an altitude of eighty-five hundred feet. On the ground German forces lit bonfires to guide the Ju 52s to the release point just northwest of Aachen, Germany.

Shortly into the flight, Witzig’s glider broke free from his tow plane when the Ju 52 pilot banked abruptly to avoid colliding with another glider. With only three thousand feet of altitude the glider had no chance of making the fort. Witzig ordered the pilot to “land on the east side of the Rhine so [he] wouldn’t have to cross any bridges.”30 Turning the glider back toward Cologne, the pilot managed to land in a field just four miles outside of Cologne. Witzig rushed to the nearest village, commandeered a vehicle, and returned to Ostheim. In the meantime the remaining ten gliders continued on toward Eben Emael. Minutes after Witzig’s glider broke free, the glider containing the second squad received the order to unhitch. The glider pilot initially refused to obey, realizing that he was only at sixteen hundred meters. The Ju 52 tried to shake the DFS 230 loose and eventually forced the glider pilot to release. With Eben Emael twenty-five miles away the glider would be forced to land short. The last nine gliders proceeded, unaware that two of their eleven squads were not in the formation. At 0410 (much earlier than scheduled owing to a strong tailwind) the gliders reached their planned release point. The Luftwaffe squadron commander, realizing that the gliders were not high enough to reach the fort, made the decision to continue on until an altitude of eighty-five hundred feet could be reached. This required entering into Dutch airspace and drawing the attention of Dutch antiaircraft guns. Nevertheless, the squadron of airplanes continued on for another ten minutes and released the gliders.

Earlier that morning, at 0030, the Belgians at Fort Eben Emael had been alerted to the movement of German troops toward the border. The commander of the fort, Major Jottrand, received a telephone call and was at his position within minutes of the alert. Standard procedure called for cupola 31 to fire twenty blank rounds every thirty seconds. This was the signal to soldiers living in town to return to the fort immediately. Additionally, it signaled those troops assigned to defend the bridges to muster at their posts. Unfortunately, the gun crew for cupola 31 could not be mustered until 0330. In the interim, it became clear to Jottrand that this was not a false alarm. He could hear heavy antiaircraft fire coming from Maastricht. His orders called for him to evacuate the barracks just outside the main entrance to the fort, move all the bedding supplies into the interior, and destroy the building so it did not obstruct the gun crews’ views of their targets. In order to carry out this directive, Jottrand had to use his gun crews to move the supplies and place the demolition. This significantly affected the crews’ ability to prepare their guns. Consequently, it was not until 0325 that casemate 23 began firing warning rounds to alert the countryside. This did not overly concern Major Jottrand because he knew German ground troops would have to cross the Dutch border before the fighting actually began, and this would allow ample time for him and his crews to get into position. In order to make the guns ready for firing, the crews were required to clean the rust-preventing Cosmoline from the barrels and bring the ammunition from its storage point to the breech. At 0400 Jottrand received word that thirty to fifty airplanes were headed in the direction of Maastricht.* Moments later his own men reported, “Airplanes are overhead! Their engines have stopped! They stand almost motionless in the air!”31 High above the fort the gliders were making their final approach.

“Objective 29 [antiaircraft gun position] was under the command of a very determined young lieutenant who, alerted to the gliders’ approach by the sentry, reacted swiftly and ordered his men to open fire.”32 The gliders took heavy antiaircraft fire, and although several were shredded by the 60mm rounds, no one was injured. The glider carrying Squad 1 dove steeply to avoid the antiaircraft fire now coming from the fort. The pilot leveled out, touched down, and braked to a crunching stop, leaving the plane a wreck but safely on the ground. The squad, led by Sergeant Neidermeier, had the responsibility for destroying casemate 18. After scrambling to get out of the wreckage, Neidermeier ran to casemate 18. With the assistance of Private Drucks, he placed his 50-kilogram shaped charge in the center of the concrete structure, pulled the fuse, and quickly extracted. The charge blew the turret to pieces, killing the two Belgians inside. Meanwhile two other members of Squad 1 placed a 12.5-kilogram charge just below the other 75mm gun. The explosion lifted the gun off its stand and killed two of the twenty-one men inside or directly below the casemate. The wounded tried to retreat, but Neidermeier and two squad members went through the breach where the gun had been and killed two more Belgians. The remaining survivors escaped, but most were severely wounded or flash burned. Neidermeier donned a gas mask and pulled one of the wounded Belgians outside away from the caustic smoke-filled interior. The task completed, Neidermeier placed an aircraft-marking panel on the outside of the casemate to inform the Luftwaffe that the area was secure. Squad 1 remained inside casemate 18 when Belgian artillery from a nearby fort began to pound the ground around them.

The glider containing Squad 2, led by Sgt. Max Maier, never made the fort. It had been erroneously released early and landed near Duren in Germany. The squad commandeered a truck and drove toward Canne. They reached the bridge only to find that the Belgians had destroyed it. Sergeant Maier was killed attempting to cross the downed bridge, but Cpl. P. Meier continued on, eventually arriving at the town of Eben Emael. Although he tried several times, Corporal Meier was never able to link up with the other squads at the fort. The members of Squad 2 who remained at Canne eventually captured 121 Belgian prisoners, but as Wenzel recalls, “Before the squad would release the prisoners [to the German guards] they asked for a receipt, so they could prove what they had done.”33

Squad 3, led by Sergeant Arendt, was assigned to destroy casemate 12. The glider containing the squad released itself from the tow plane and made a perfect approach. As the glider breezed over the fort, the Belgians opened fire. The tracers were high and the pilot landed the DFS 230 just thirty yards east of the objective. Arendt and his men hurried from the glider and charged the casemate. To their surprise, no Belgians inside the massive 75mm gun turret attempted to stop them. When they reached the casemate the squad had trouble affixing the 50-kilogram shaped charge to the gun, so they elected to place the smaller 12.5-kilogram charge at the rotating base. They pulled the fuse and ran. As it turned out, there were several Belgian soldiers inside. They were completely unaware of the Germans’ presence.

The results of the explosion were similar to Squad 1’s. The blast tore the gun from its mount, crushing a Belgian soldier and wounding several others. Smoke and fire, fueled by propellent stacked inside, engulfed the chamber. The Germans fired their machine pistols through the opening, then cautiously proceeded into the interior. Some of the wounded Belgians had been evacuated by their comrades, but Arendt found three soldiers left behind. These men were pulled to the surface.

Arendt continued to move further into the recesses of the fort. Following voices that led to an elevator shaft, he dropped a 3-kilogram charge down the shaft and either severely wounded or killed those Belgians below. Arendt proceeded down a nearby stairwell until he arrived at another level. A steel door prevented his incursion into the center of the fort, so he returned to the surface. Squad 3 remained topside, ensuring that no Belgians attempted to break out. Belgian after-action reports showed that only one of the twelve-man gun crew had survived the assault uninjured.

Squad 4 was led by Sergeant Wenzel and was assigned casemate 19. The casemate was cut into the side of a hill with four gun openings on the face of the casemate pointing toward the northwest. On top of the casemate (and flush with the ground) was a steel observation cupola. As soon as the glider landed, it was taken under machine-gun fire by the Belgians in the cupola. The squad attacked the Belgians, forcing the machine gunners inside to close the steel observation doors from which they were firing. Wenzel dropped a 3-kilogram charge down the observation periscope that protruded from the cupola. The explosion rocked the cupola, but the Belgians continued firing. Wenzel then placed a 50-kilogram charge on top of the cupola, but the explosive did not fully detonate and failed to penetrate the six-inch steel dome. Nevertheless the explosion did render the cupola inoperable and forced the Belgians to retreat into the lower level. Wenzel moved down from the top of the hill until he was even with the gun openings. He placed another 50-kilogram charge on the casemate. This time it blew a large hole through the concrete and killed or wounded everyone inside. Wenzel elected to position his men beside the now abandoned casemate and await further orders. It had been fifteen minutes since Squad 4 had landed.

Squad 5, led by Sergeant Haug, landed and immediately assaulted cupola 23. The charge dislodged the gun mounts and reduced the rate of fire, but it failed to prevent the gun from firing altogether. Haug and his men subsequently attacked casemate 30, although this was not part of the plan. The explosion killed at least two Belgians but again failed to completely neutralize the guns. Throughout Squad 5’s assaults, the men received heavy fire from a storage shed located between casemate 30 and cupola 24.*

At the same time that Haug was assaulting his objectives, he noticed Squad 8 was receiving effective fire from the storage shed and casemate 31. Haug and some of Squad 8’s men attacked the shed but were repelled and lost two dead and several wounded. About that time Belgian artillery fire from a nearby battery began to rain in on the fort. Haug and his squad took cover in a nearby ditch. Several times they attempted to withdraw to a safer position but were immediately taken under fire. Squad 5 remained in the ditch until later that evening when they slipped out under cover of darkness.

The glider carrying Sergeant Harlos’s Squad 6 was hit several times by antiaircraft fire. The pilot was forced to land in a field of concertina wire which brought the airplane to a jarring stop. The squad had difficulty exiting the glider and breaking into open ground owing to the thick barbed wire the Belgians had placed around the northern end of the fort. When they reached their objective, cupola 14, they found another squad had already destroyed it. As it turned out, the objective was a false cupola. Where the cupola had been, however, there was a machine-gun emplacement dug into the earth. Harlos decided to place a 50-kilogram charge in the hole and detonate. The resulting explosion blew a hole into the inner fortress, causing a cave-in of concrete and earth. His task complete, Harlos established a machine-gun position to prevent reinforcements from coming across either the canal or the moat. During the remainder of the day Squad 6 engaged several Belgian troop movements and kept the north end secure.

Sergeant Heineman’s Squad 7 was tasked with destroying cupola 16 at the north end of the fortress. It was not until they arrived and placed their explosive on the cupola that they realized it was a dummy emplacement. Nonetheless the task was completed in a matter of minutes.

The glider carrying Squad 8 had made a harrowing approach to the fort. In an effort to avoid the antiaircraft fire, the pilot had come in below the east wall next to the canal and pulled up at the last minute to settle down just thirty yards from casemate 31. Led by Sergeant Unger, the squad came under immediate small-arms fire from the storage shed and casemate 31. Part of the squad, with help from Squad 5, attacked the shed while Unger and two men ran to the casemate and placed their 50-kilogram charge. After pulling the fuse, Unger placed a 12.5-kilogram charge on a nearby fortress exit, destroying the steel doors and sealing the Belgians’ escape route to the surface.

Although the Belgians at casemate 31 were warned of the attack thirty minutes before Unger landed, they were unable to get the guns ready for action. The door to the ammunition locker was locked and no one could find the keys. After the locker was opened, the elevator that carried the ammo to the gun failed to function, so only a limited amount of 75mm rounds could be carried to the breech. As the chief of the section loaded the first round in the chamber, Unger’s 50-kilogram charge detonated, killing two Belgians and wounding several others.

Next Unger moved to destroy the cupola on top of the casemate. The 50-kilogam charge appeared to do little damage to the steel dome, but in actuality the penetrating force of the explosion completely destroyed the inner workings of the 75mm guns and rendered them totally inoperable. The squad was then directed to move north to Wenzel’s position. As they attempted to extract from their position, they received heavy machine-gun and incoming artillery fire. Unger was killed, and only three men managed to reach Wenzel’s position.

The glider carrying Squad 9 received substantial antiaircraft fire and flak but still managed to land within sixty yards of their objective at casemate 13. Like Squad 6 they also landed in a jungle of barbed wire and began receiving ineffective fire from the hangar. Germans from the other squads managed to subdue the Belgians in the hangar, allowing Squad 9 to exit their glider and move to casemate 13. Led by Sergeant Neuhaus, the squad assaulted the target, using flamethrowers to push back the Belgians manning the machine guns inside the casemate. After an unsuccessful attempt to place a 12.5-kilogram charge over the machine guns, Neuhaus placed a 50-kilogram charge on the steel door leading to the interior of the casemate. The resulting explosion blew the door inward and destroyed the supporting wall. Neuhaus stepped in and found the Belgians on the floor in shock. His task completed, he set up a defensive position and sent a runner to find Witzig and report their results. (None of the squads knew that Witzig’s glider had failed to reach the fortress.)

Squad 10, led by Sergeant Huebel, had originally been assigned as a reserve force. After landing, Huebel received orders from Wenzel to attack casemate 26. This had been Squad 2’s target, but their glider never arrived at Eben Emael. Huebel and one other squad member assaulted the observation dome, placing a 12.5-kilogram charge on top. The resulting explosion either killed or wounded the crew manning the gun, for no further firing occurred for the remainder of the operation.

By this time all the squads had completed their missions. Wenzel stated later, “Our main objective was to take out the guns that could destroy the bridges, and that mission was accomplished in the first fifteen minutes.”34 Now all that remained was to ensure the Belgians did not mount a counterattack before infantry from the German 4th Armored Division arrived.

Wenzel contacted Captain Koch via radio and informed him the fort was under German control. Preplanned bomber support began to arrive almost as soon as the glidermen had completed their missions. “We didn’t have radio contact with any of the other groups, only with Captain Koch. So we laid panels on top of the cupolas to let the [Stuka] pilots know we had them.”35

With the German positions marked by panels, the Stukas began dropping bombs against some of the Belgians still putting up resistance. Also within the hour, more ammunition was air-dropped to Wenzel and his men.

With Witzig still stranded in Germany, command of the detachment was supposed to fall to the next senior officer, Lieutenant Delica. Delica however was a Luftwaffe communications officer with no ground experience. He had been assigned to the detachment to coordinate air support from the Stuka divebombers.36 Consequently, the major tactical decisions implemented in the first two hours were all the work of Wenzel.

At approximately 0630, two hours after the assault had begun, Witzig arrived, landing near casemate 19. He had managed to requisition another tow plane to get his glider airborne. He arrived late, but much to the delight of his detachment. The initial plan called for the glidermen to hold the fort for approximately four hours until the infantry arrived. By noon, however, it was apparent the commandos would have to defend their position for longer than planned.

Throughout the remainder of the day the Belgians called in artillery from a nearby fort, hoping to force the Germans off the exterior of Eben Emael. Some of the squads remained inside the bombed-out casemates, protecting themselves from incoming rounds and trying to ensure that the Belgians did not gain access to the top of the fort through the openings in the casemates. Other Germans took up defensive positions on the outside, periodically engaging Belgian troops that had managed to surface or that had been in the topside storage shed and barracks. Squad 3 under Sergeant Arendt pursued the Belgians into the fort, destroying exterior access routes as they went. The Belgians attempted several counterattacks, but a lack of infantry weapons (grenades, assault rifles, and squad machine guns) and infantry tactics (all the Belgians were artillerymen) caused them to be no match for the Germans. An infantry unit of forty men from a nearby post (commanded by Captain Wagemans) was called in at 1030 to attempt to evict the Germans. The Stukas curtailed the Belgians’ enthusiasm by bombing the infantrymen at each attempted attack. By 1300 the Belgians had repaired casemate 4 and begun to open fire on the glidermen. Witzig ordered Sergeant Harlos’s squad to silence the guns by placing a 12.5-kilogram charge against the embrasure. The tactic proved effective, and casemate 4 stopped firing.

In the meantime the commander of Eben Emael, Major Jottrand, contacted another infantry post at Wonck, approximately three miles away. He ordered a force of 233 men led by Lieutenant Levaque to attack the Germans. However, every time the Belgians began their march from Wonck to Eben Emael, they were bombed by Stukas. Consequently, by the time the troops reached the fort they were in no condition to fight, having sustained over 50 percent casualties. The infantry force already at the fort was never able to link up with Levaque. At 1745 Levaque attempted to take a small force of eight men and attack casemate 12. The glidermen spotted the force attempting to reach the casemate and pinned them down with machine-gun fire. Soon afterward, the Stukas began pounding the Belgian position, and after an hour Levaque retreated back to the fort’s entrance.

At 2000, Major Jottrand decided to mount a counterattack of his own. He mustered sixty men and planned to sneak to the surface through an emergency exit. Unbeknownst to the Belgians, the Germans had already discovered the exit, and just as Jottrand’s men were approaching the surface the Germans detonated another charge. The blast left a gaping hole in the fort. Jottrand, realizing he had lost the element of surprise, elected to stay inside and fortify his position to prevent German incursion into the interior.

Throughout the remainder of the early evening the Germans came under constant but ineffective fire from various Belgian positions. Witzig decided to consolidate his position. “I pulled my forces back in anticipation of a counterattack on the north end.”37 It was then that Witzig realized that casemate 17, which was positioned alongside the Albert Canal, could still engage advancing German infantry.* Although the glidermen tried three times to destroy the guns, they were unsuccessful each time. Wenzel said later, “We tried to lower charges down on a rope, but the gun kept firing.”38

At 2030 Jottrand issued defensive orders for the fort. Throughout the night incoming artillery from both Belgian and German batteries, along with periodic explosions from Witzig’s men, kept the defenders of Eben Emael in a constant state of fear. The men inside the fort were afraid that the Germans would breach the makeshift defenses they had erected. The interior of the fort was a shambles. The explosions had cut off power to many areas. There was minimal lighting and no air-conditioning or heat, and smoke permeated the majority of the spaces. All of these conditions added to the Belgians’ apprehensions. Additionally, “the Belgians didn’t know how many Germans there were [on the surface of the fort].”39

Throughout the night, Witzig’s men continued to assault those casemates and cupolas that were still harassing the Germans. By morning the fort was virtually out of commission, although Stukas continued to bomb the heavy guns until approximately 1200. At 0830 Witzig was officially relieved by elements of the 151st Infantry Regiment. He buried his six dead and departed Eben Emael at approximately 0930. At 1215 Major Jottrand sent Captain Vamecq to meet with the Germans and arrange a surrender of the fort. Before Vamecq could discuss details of the surrender, Belgians from inside Eben Emael came pouring out with their arms raised in defeat. At exactly 1227, Jottrand officially surrendered the fortress at Eben Emael. The Belgians had lost twenty-five killed and sixty-three wounded, and the Germans had destroyed ten of the seventeen casemates and cupolas. Before they surrendered, the Belgians destroyed casemate 33 and the 120mm guns, leaving only five operational defenses.



There is little debate that the assault on Eben Emael was one of the most decisive victories in the history of special operations. Sixty-nine German glidermen engaged and soundly defeated a Belgian force ten times their size protected by the largest fort of its day. It is the best example in modern times of a well-defined plan thoroughly rehearsed and flawlessly executed.

Were the objectives worth the risk? Hitler felt it was absolutely necessary to check the Anglo-French forces in Belgium and northern France by convincing them that the main German attack was coming through Holland, across the Albert Canal, and down from the north. In order for this deception to work, the Germans had to get two corps (Schmidt’s 39th Panzer and Hoepner’s 16th Panzer) into Belgium as soon as possible. The failure to check the Anglo-French forces would allow those units to reinforce the French Ninth and Second Armies, which were guarding the axis of the real main assault coming through the Ardennes. The only access into Belgium was across the Albert Canal. Securing the three bridges guarded by the fortress at Eben Emael was the key to German success in that region. Had the bridges fallen and Eben Emael survived the glider-men’s attack, the Belgians could have delayed the German advance long enough for the Anglo-French forces in the north to be redeployed to the south. Consequently, there should be no question that destroying the fort was necessary and the risks worth the effort.

Was the plan developed to maximize superiority over the enemy and minimize the risk to the assault force? In the case of Eben Emael it is reasonable to ask if the Luftwaffe alone could have rendered the fort inoperable, thereby minimizing the risk to ground forces. Discounting the three bridges, which had to be seized quickly by ground forces to defuse the explosives, could Stuka divebombers have destroyed the fort’s guns, which threatened the German armored advance? As the case study shows, the Stukas were very successful at deterring the Belgian infantry from reinforcing and counterattacking the glidermen. However, they had little effect on the steel and reinforced concrete casemates and cupolas. The defenses had been designed to withstand aerial bombing both in the way they were built and in where they were positioned. Casemate 33 withstood more than twenty-four hours of constant bombing before the guns eventually failed. It was the introduction of the shaped charges, which were able to penetrate the hardened gun positions, that made the fort vulnerable. Additionally, speed in destroying the guns was essential. Had the glidermen failed to render the guns inoperable within the first half hour, the Belgians could have fired on their own bridges to halt the German advance.* No other force offered the advantages of surprise, speed, and destructive capability that the glidermen did.

Was the mission executed according to plan, and if not, what unforeseen circumstances dictated the outcome? The plan to seize Eben Emael did not change much from its original conception. It was rehearsed in various forms from November 1939 to May 1940, and with a few notable exceptions it was executed exactly as planned. As mentioned, neither Lieutenant Witzig nor Sergeant Maier’s squad arrived with the other elements. However, the plan had foreseen such contingencies. Witzig’s role was command and control. When he failed to arrive, Wenzel ably took over. Later Wenzel remarked, “The officers had trained all of the men so well that the officers were expendable.”40The plan also called for one squad in reserve. When Maier’s squad failed to arrive, Wenzel ordered Sergeant Huebel to attack casemate 26. Resupply and close air support were both coordinated ahead of time and were instrumental in allowing the glidermen to sustain their positions and prevent Belgian counterattacks.

The raid appears to have been executed as planned and within the scope of possible contingencies. The only shortfalls were the squads’ failure to destroy casemate 17 and the apparent lack of coordination on the glider launch. Although casemate 17 had been targeted as a secondary objective for Squad 6, the casemate was not in a position to destroy the bridges; it could only harass the German infantry. Therefore, failing to render it inoperable did not impinge on the initial success of the mission. Nonetheless it was a target, and no viable plan was devised to render it inoperable.

A full-scale rehearsal of the glider launch was never conducted for fear of compromising the operation. Had Koch been able to secure a discreet landing field he should have conducted at least one launch sequence involving all gliders and accompanying tow planes.

What modifications could have improved the outcome? Considering the magnitude of the problem and the fact that all the primary objectives were destroyed within twenty minutes, it is doubtful that any modifications to the plan would have improved upon success.

Relative Superiority

The assault on Eben Emael may be the best representation of relative superiority in modern-day special operations. The attacking force was numerically inferior—outnumbered ten to one. The fortifications surrounding Eben Emael were some of the finest of their day. And yet a small, lightly equipped force destroyed the fort’s main batteries in twenty minutes and eventually compelled the fort’s commander to surrender the entire garrison. Figure 2-4shows that the attacking force became vulnerable as they began their final approach to the fort. The machine guns tasked with antiaircraft duty actually hit six of the nine gliders as they descended. The Germans’ vulnerability was minimized by surprise, and the probability of mission completion curve rose sharply as each glider made its landing. With all the gliders on the ground, relative superiority was achieved, that is, a condition existed where the Germans had a decisive advantage over the Belgians. The Germans’ probability of mission completion strongly outweighed their probability of failure. On the graph this is shown as a significant rise above the relative superiority line. The Belgians didn’t realize the precarious position they were in; they viewed the fortress as invulnerable to infantry attack. Even with no one manning the casemates, it would have been difficult for a conventional force to destroy the thick concrete bunkers. With the 50-kilogram shaped charges, however, all the German glider-men had to do was place the charges, pull the nine-second fuses, and stand back. Clearly the glidermen were vulnerable between achieving relative superiority and mission completion. However, by using prerehearsed tactics and moving quickly, they were able to subdue the machine gunners in the casemates and place their charges. Within fifteen minutes of landing, all the primary casemates that threatened the three bridges were destroyed.

Even if we define mission completion as the surrender of the fortress and extend the graph out twenty-four hours, the additional area of vulnerability would be negligible owing to the close air support provided by the Stukas and the bombers’ ability to suppress any Belgian counterattack.

Fig. 2–4. Relative Superiority Graph for the Assault on Eben Emael

Could a large conventional force have achieved the same results? No. The fort was designed to repel ground forces, both armored and infantry. Had the Germans attempted a conventional assault they may have been able to destroy the fortress, but not before the Belgian guns destroyed the bridges. A parachute assault would not have been possible for a large force for the same reasons it was discounted for a small force: the parachutists would be too widely dispersed, and they couldn’t carry enough ordnance. And, although the surface of Eben Emael was sufficient to handle nine gliders, a large gliderborne force would not have had enough room to land.

In the end, relative superiority was achieved because the attacking force had superior technology, national-level intelligence, excellent security, realistic and detailed training, and highly motivated troops. These factors reduced the frictions of war to a manageable level and provided the Germans a decisive advantage over the entrenched Belgians. In the next section we will see how adhering to the principles of special operations allowed the Germans to gain relative superiority and sustain it until mission completion.

Principles of Special Operation

Simplicity. Although Hitler is often criticized for his lack of strategic and tactical acumen, his plan for seizing the fort at Eben Emael was brilliant both in its strategic vision and in its tactical simplicity. Prior to the assault no one would have believed that Eben Emael could be taken at all—much less by so small a force. In 1938, Lt. Albert Torreele toured the fortress, and later, as the Belgian attaché to the United States, he stated:

An officer member of the garrison of the fort led us to many of the outer defences and showed what each was intended for. We went to the walls and looked over countless rows of barbed wire. He led us to the only door on the surface set deep in concrete. It appeared like the heavy steel door of a bank vault. From here infantry in reserve would issue to repel any enemy fortunate enough to get by the tough ground defences. He took us deep into the interior and we trudged many miles to the end of the tunnels, visiting the crews and the guns of emplacements we had seen on the surface … I got the impression of tremendous power and first rate efficiency. I was convinced nothing could happen.41

The problem of seizing the fort seemed insurmountable. But by limiting the objectives, using good intelligence, and devising innovative tactics and technology, the Germans were able to simplify the problem significantly.

Witzig, who developed the specifics of the plan, knew that only certain casemates or cupolas had guns capable of reaching and destroying the three bridges, and this was Hitler’s main concern.42 Other casemates could still lob 75mm rounds on the advancing infantry regiment and panzer division; but by attempting to destroy all nineteen casemates and cupolas, Witzig would have had to either increase the size of his assault force or give each squad multiple targets. The assault on Eben Emael already required Witzig’s entire engineer platoon. Consequently, additional forces would have had to come from outside the platoon; and to break unit integrity on a mission this critical was considered unacceptable. Giving each squad an additional target would also have significantly complicated the operation. As it was, each squad of seven or eight men carried two 50-kilogram shaped charges, two 12.5-kilogram shaped charges, three bangalore torpedoes, a flamethrower, and a host of other ordnance and assault equipment—all for one casemate or cupola.* Adding one more target to each squad would have complicated the command and control, required additional fire and movement training, and increased the number of gliders to handle the added weight of twice the ordnance. After consultation with Koch, Witzig chose to forgo some of the smaller casemates and concentrate on the real threat.

Intelligence for the operation helped simplify the plan by reducing the number of unknown factors. Witzig knew exactly how many casemates and cupolas there were and where they were located. He knew the dimensions of the landing area and what surface obstacles could impede a glider assault. He had blueprints that showed the inside of the fortress and the emergency exits used for conducting a counterattack. All of this intelligence allowed Witzig to plan his training around a realistic scenario: the demolition training was against casemates that resembled Eben Emael’s bunkers, the gliders learned to land in an area comparable to the surface of the fort, and even the physical training (running the exact distances, climbing the casemate walls) was based on intelligence provided to Witzig.

Innovation played a major role in simplifying the plan to assault Eben Emael. Although the surface of Eben Emael had a large enough drop zone for a small number of parachute troops, the Germans, after conducting several test drops, concluded that the platoon would be too widely dispersed to be effective. Additionally, parachutists could not carry enough ordnance, and the sound of propeller-driven jump aircraft would have prevented surprise.

Although gliders had been around for quite some time, they had never been used in actual combat. Their unique capability to land troops and their equipment within fifteen to thirty yards of the target was an undeniable advantage owed to new technology. The DFS 230 was newly designed and modified specifically to meet the demands of landing on a grassy strip. Even today there are very few air insertion techniques that can deliver ten men and their equipment with that level of accuracy.

The most significant technological innovation was, of course, the shaped charge. This was the first time this explosive device had ever been used in combat. The shaped charge’s ability to penetrate both the six-inch-thick steel cupolas and the reinforced concrete of the casemates was unquestionably the single most important factor in the success of the mission. Within the first twenty minutes the glidermen had destroyed casemates 18, 12, 19, 13, and 26, and partially immobilized casemate 30. Additionally, they destroyed cupolas 14, 16 (false cupolas), 23, and 31. The Belgians were so stunned by the swiftness with which their defenses were incapacitated that they never recovered. The glidermen continued to inflict severe damage on additional cupolas and machine-gun embrasures with both the 50-kilogram and 12.5-kilogram shaped charges.

The more difficult a plan is the longer it will take to execute, and consequently the greater will be the area of vulnerability. By limiting the objectives and using good intelligence and innovation to overcome the obstacles, a plan can be reduced to its simplest terms. And a simple plan is the base upon which rests the remainder of the operation.

Security. The Germans’ operational security throughout the planning and preparation for the assault on Eben Emael was extensive but not overbearing. From the time Koch received his orders until the day of the attack, only the assault element leaders (the officers) were told the exact name and location of the objectives. Security was considered paramount to achieving surprise. Assault Force Granite changed its name each time it moved to a new location. The troops were given cover stories and cover names. Guards were assigned to each unit to ensure no “inadvertent” information was divulged. Letters were censored by Captain Koch’s staff. In the last days prior to the assault, all personnel were restricted to the base and, when necessary, transported in covered furniture vans to hide their presence. An operational deception plan placed phoney news stories in local papers to conceal the glidermen’s activities, and special units set off smoke makers to hide the force from aerial observation. But even with all these measures, the operational security never inhibited proper preparation. With only one exception, a full-scale launch of all gliders, all phases of the mission were rehearsed again and again.

It is important for security personnel to understand what aspects of the mission absolutely have to be concealed. This allows operational security to be more effective and less restrictive overall. Even with all the Germans’ operational security, the Belgians at Eben Emael were prepared to halt an attack, even a gliderborne attack.

The “Phoney War” had been brewing since 1939, with anticipation of a German full-scale attack into Belgium and Holland. On the days preceding 10 May, the fort at Eben Emael had several false alarms and all the soldiers in the fort were recalled to their stations. The Belgians realized that the Germans might attack at any moment. They just were not worried because the fort seemed indestructible, particularly to an airborne assault. The surface of the fort had barbed wire, antiaircraft guns, a tank moat, and infantry fighting positions. Had the Germans attempted a parachute drop, the parachutists would have been cut to pieces. So it was important for operational security to hide the glider insertion method and to conceal the time of the assault. Although it was important to conceal the name of the unit, the personnel involved, and the demolition training on the casemates, it is doubtful it would have dramatically affected the outcome of the mission had any of this information leaked out. Even if the Belgians had found out about the glider training, it is arguable whether they would have altered the surface defenses of the fort. Why should they have? What could glider-borne infantry forces expect to achieve against concrete casemates and steel cupolas surrounded by machine guns and barbed wire? Even if the Belgians had learned about the shaped charges, it is doubtful that they could have developed countermeasures to protect the casemates. It was the timing of the mission that was most crucial to conceal. Had the Belgians known the time of the attack, they could easily have prevented the Germans from succeeding, even with their ineffective surface defenses. A couple of well-manned machine guns could have held the glidermen at bay and prevented them from ever gaining relative superiority. Consequently, operational security must take into account the nature of a special operations mission; it is the method of insertion and the timing that are the most crucial. The fact that a mission is pending should be concealed, but not at the expense of proper preparation.

Repetition. Sergeant Wenzel remarked during our interview that “at first the plan to assault Eben Emael didn’t look good. I thought, ‘we’ve really gotten ourselves into it this time.’ But as we practiced more and more on the bunkers, it became apparent it would work.”43 This comment speaks volumes about the importance of realistic rehearsals.

On 3 November 1939, Koch received his mission orders. From November until May, Storm Detachment Koch, which included Witzig’s Granite Force, prepared for the assault on Eben Emael. Although some of this time was spent recruiting glider pilots and sending Witzig’s engineers to advanced demolition school, at least four months’ time was used in direct preparation for the attack. Witzig was known as a detail man, and during the planning and preparation phase he ensured no detail was left unaddressed. The glider pilots, both the Luftwaffe and the more skilled civilians, flew dozens of flight profiles that corresponded to the landing on Eben Emael. At first these flights were done without full loads, but eventually all Witzig’s engineers and their equipment were placed in the DFS 230 and “flown many, many times.”44 Before 10 May, every pilot could take off at night, fly the profile, and land on a grassy surface within fifteen to thirty yards of his target. Witzig even ensured that all the glider pilots were capable of using the weapons and shaped charges carried by the engineers.

While the pilots were flying, the engineers were conducting mock drills: first in a large field with nothing but markers to signify the casemates, and then on actual casemates and cupolas on the Czech and Polish borders. Witzig’s men conducted hundreds of partial drills and at least two full-dress rehearsals with the gliders and full equipment. As previously noted, the only aspect of the mission the Germans didn’t conduct was a full glider launch of the entire Storm Detachment Koch. Unfortunately, since they had practiced only in individual elements, the logistic problem only became clear when it came time to orchestrate the entire launch sequence. Although Witzig’s group launched without difficulty, the remaining gliders were several minutes late taking off when the tow planes and gliders began to stack up. This time delay cost precious minutes and was responsible for the failure of Assault Force Iron to gain surprise at Canne, which resulted in the bridge’s destruction and the loss of several German lives.* Repetition as manifested in realistic rehearsals is the litmus test of simplicity. Concepts that seem easy on paper may in fact be difficult in practice. Consequently, it is imperative that all facets of an operation be rehearsed prior to the mission.

Surprise. Most historians view the raid on Eben Emael as a classic example of employing surprise to gain a tactical advantage over the enemy. They cite Belgian unpreparedness to defend against a glider assault as the main reason for the fort’s demise. It is interesting to note just how prepared the Belgians were and what the element of surprise really contributed to the Germans’ success.

On 10 May at 0030, the local Belgian command headquarters at Liège notified the fort at Eben Emael of German movement across the Dutch border. This was the third alert that month, and it received an unenthusiastic response from the troops stationed in the nearby town. Nonetheless most of the available Belgian defenders were at their posts by 0300. At 0315, one hour before the gliders appeared in the sky, Lieutenant Longdoz reported that his crews were manning the four pairs of multiple-mount antiaircraft guns. At approximately 0400 Belgian outposts reported inbound aircraft at an altitude of four to five thousand feet.

When the gliders cast off from the tow planes at 0415, many of the Belgian gun crews stood dumbfounded as the silent aircraft descended on the fort. There was a momentary delay before the antiaircraft and light machine guns began firing; nevertheless six of the nine gliders were hit by gunfire, although none were seriously damaged. As the gliders landed, most were immediately taken under fire by machine guns from the cupolas or the nearby storage shed. Although there were no built-in defenses against glider assault (like the triangular steel obstacles that protected against tanks), the surface of the fort was ringed with barbed wire (which many of the gliders landed in) and fighting positions to counter enemy infantry troops. There is no doubt that the Belgians were surprised by the glider assault, and I would argue that they were unprepared to deal with the situation.

The real surprise, however, was not the manner in which the Germans inserted; it was the swift employment of the 50-kilogram shaped charges that caught the Belgians completely unprepared. Although the casemates were constructed to withstand both enemy artillery and aerial bombardment, the shaped charge was new technology, and there were no countermeasures available. To the Belgian defenders, the gliders and their German commandos presented an insignificant threat provided that the Belgians could retreat into the safety of the hardened fortress. From their steel cupolas, they could employ overlapping fields of fire to decimate any infantry on the surface of the fort. The Belgians were prepared to deal with both air and ground assaults. What they were not prepared to deal with was the sudden and complete destruction of their fortified casemates and cupolas. This was the real surprise.

Speed. It was 0425 when the first glider landed atop the fortress at Eben Emael. Within the first twenty minutes all squads had reported back to Wenzel that their missions were complete, well before the allotted sixty minutes. Had the glidermen extracted from the fort at that moment, they still would have achieved their major objective of destroying the main guns covering the bridges at Canne, Vroenhoven, and Veldwezelt. The special operations aspect of the mission was complete. However, the original plan called for Witzig to hold the fort for four hours until he was relieved by the engineer battalion of the 151st Infantry Regiment. Consequently, he was prepared to “go conventional” immediately following the accomplishment of the main objective. His men, under the guidance of Wenzel, dug in and positioned themselves to repel Belgian counterattacks. Even with preparations for an extended stay, problems began to arise as the glidermen were forced to hold the fort longer than planned.

Special operations forces, by virtue of their insertion methods, are generally unable to sustain operations for an extended period. Whether they insert by glider, parachute, or C-130 aircraft, commandos are limited in their firepower by what they can carry. Speed is essential to minimize time on target and maximize available resources. Witzig’s company had the advantage of being within range of continuous air support, a luxury not normally available to behind-the-lines operations. Nevertheless, as time passed, several counterattacks were attempted, first by Captain Wagemans and his forty Belgians, then by Lieutenant Levaque and his reinforced company from Wonck. Additionally, Major Jottrand tried several times to oust the glidermen from the surface of his fort. Without Luftwaffe support, Witzig would not have been able to receive ammunition resupply nor the fire support he clearly needed to accomplish the holding action.

Even with this prolonged action there can be little doubt that the first several minutes dictated the outcome of the entire mission. Witzig spent six months of training to ensure every aspect of the initial phase, from exiting the glider to assembling the shaped charge to reporting the results, was completed as quickly as possible. Unfortunately for the Belgians his training paid off.

Purpose. How important is being personally committed to a mission? Corporal Alefs of Squad 7 remarked after the battle, “We had been cooped up for months and had been transformed into killers. Everything we had done was in preparation for this hour … There was unyielding determination in each man’s eyes. Those who are our friends, are our strong loyal friends; those who are our enemies will find us unyielding enemies. With this feeling we could search out the devil in hell!”45

The principle of purpose is always viewed from two directions: the purpose of the mission as stated in the operation order and the sense of purpose or personal commitment that each soldier brings to the battle. First, the individual soldier must understand the purpose of the mission so that, if required, he can react without supervision, knowing that his actions are consistent with the mission directive. As Wenzel said later, “They [the troops] must be able to recognize the situation and act accordingly.”46 This ability to “act accordingly” requires the plan to be clearly articulated to the troops. In the case of Eben Emael the individual soldier had a simple task: exit the glider, place the charge on the casemate, pull the fuse, extract, and then survive until relief arrives—that was it! Understanding the purpose of his individual mission was easy. However, understanding the overall picture while being counterattacked by the Belgians also needed to be simple. Fortunately, it was. When Witzig failed to arrive to control the actions at the objective, Wenzel quickly took command. He knew exactly what had to be done. He notified Koch that the casemates were destroyed and then consolidated his forces and set up defensive positions. Wenzel had a clear understanding of where all the squads were, even though he could not see them from his position. When it became apparent that Max Maier’s squad had not arrived, Wenzel quickly redirected an available squad to destroy Maier’s assigned target. Wenzel could also visualize the Belgians’ situation and was prepared to counter their efforts, which he did successfully several times. Although Wenzel became the “hero of Eben Emael,” the purpose of the mission was so clearly understood by most if not all of the participants that any of them probably could have commanded the actions at the fort.

There are countless reasons to be personally committed to a mission. Whether the commitment is for God, country, or self, a sense of purpose must be instilled into each soldier. It may never be needed if the operation goes according to plan, but when the frictions of war are at their peak, and the enemy is threatening to repel the attack, a sense of purpose is absolutely necessary. There are several examples of this sense of purpose during the assault on Eben Emael. To Rudolf Witzig, a sense of purpose was instilled through the knowledge that Hitler had personally planned and directed the operation and that Witzig, as the mission commander, was responsible for its outcome. Witzig was so committed to the purpose that even though his glider was forced to land short of the fortress, he managed to arrive at Eben Emael three hours later, in the middle of the battle. Wenzel, although shot in the head by a sniper (causing a scar that he still bears today), continued to direct his portion of the operation. After destroying casemate 12, Sergeant Arendt, leader of Squad 3, seized upon the opportunity to enter the fortress. Without regard for his own life, he proceeded deep into the fort, dropping 3-kilogram charges as he went. This act of boldness frightened the Belgians so badly that they reconsidered any attempts to counterattack through that opening. The Germans were “merciless” in their attack,47 while, according to Witzig, “[the Belgians] didn’t have the fighting courage.”48 Without a sense of purpose it will be difficult to overcome the “stronger form of warfare.” In the case of the assault on Eben Emael the Germans had purpose, and the Belgians apparently did not.


1. Charles E. Kirkpatrick, “Simple Deceptions Pay Off,” World War II (July 1991): 44.

2. Anthony Farrar-Hockley, Student (New York: Ballantine, 1973), 66.

3. “Student and the Capture of Crete,” in John Westwood, Patrick Jennings, and Judith Steeh, Strategy and Tactics of the Great Commanders of World War II and Their Battles (New York: Gallery, 1990), 43.

4. Rudolf Witzig, interview by author, trans. Colin J. Kilrain, tape recording, Munich, Germany, 26 June 1992.

5. Helmut Wenzel, interview by author, trans. Colin J. Kilrain, tape recording, Celle, Germany, 24 June 1992.

6. James E. Mrazek, The Fall of Eben Emael (Novato, Calif.: Presidio, 1991), 49.

7. Wenzel, interview.

8. Witzig, interview.

9. Ibid.

10. Ibid.

11. James Lucas, Storming Eagles: German Airborne Forces in World War Two (London: Arms & Armour, 1988), 20. Lucas alludes to the fact that the landing area of Eben Emael was “very small” and therefore required exceptional pilots. Although the area is relatively small compared to a conventional glider landing strip, it was well within the capabilities of the average pilot. Compared to the landing area atop Gran Sasso, where Mussolini was rescued, Eben Emael was massive.

12. Witzig, interview.

13. Ibid.

14. Ibid.

15. Ibid.

16. Wenzel, interview.

17. Witzig, interview.

18. Kirkpatrick, “Simple Deceptions,” 47.

19. Witzig, interview.

20. Mrazek, Eben Emael, 54.

21. Ibid., 60.

22. Witzig, interview.

23. Russell Miller, “The Storming of Eben Emael,” in The Commandos, World War II (Alexandria, Va.: Time-Life, 1981), 10.

24. Witzig, interview.

25. Ibid.

26. Ibid.

27. Ibid.

28. James Lucas, Kommando (New York: St. Martins, 1986), 56.

29. Witzig, interview.

30. Ibid.

31. Mrazek, Eben Emael, 83.

32. Lucas, Kommando, 64.

33. Wenzel, interview.

34. Ibid.

35. Witzig, interview.

36. Lucas, Kommando, 23. Lucas reports that Lieutenant Delica had communications with the Stukas and was directing the air strikes on the Belgians.

37. Witzig, interview.

38. Wenzel, interview.

39. Witzig, interview.

40. Mrazek, Eben Emael, 111.

41. Ibid., 31–32.

42. Witzig, interview.

43. Wenzel, interview.

44. Ibid.

45. Mrazek, Eben Emael, 65.

46. Wenzel, interview.

47. Ibid.

48. Witzig, interview.

*In an effort to conceal the existence of the airborne forces, the 7th Air Division was assigned to the Wehrmacht but was controlled by the Luftwaffe. All the forces that participated in the assault were German air force.

*Information in a letter from Dr. Gunther Reibhorn of Salzburg to Col. James Mrazek, author of The Fall of Eben Emael. Dr. Reibhorn’s father was part of the map-making team that produced the models and maps for the attack on Eben Emael. Dr. Reibhorn reported that Witzig’s assault element was apparently never aware of the supersized model and only relied on the table model for planning. My interview with Colonel Witzig later confirmed this fact.

*The glider assault on Eben Emael was the first event during Operation Yellow (Fall Gelb), the blitzkrieg into Belgium. Roger Edwards, German Airborne Troops (New York: Doubleday, 1974), 71, states that the Germans also used Fallschirmpuppen, or paratrooper dummies, to distract the Belgians as the offensive began.

*Witzig said later that the small structure was visible on the aerial photos, but it was not determined until after the assault that it was just a wooden storage shed.

*Casemate 17 wasn’t a primary objective because it couldn’t destroy the bridges, but it could fire in the general direction of the advancing troops, so Witzig wanted the casemate silenced.

*Although not well documented, cupola 23 fired upon and destroyed a lesser-known bridge at Lanaye.

*Sergeant Harlos and Squad 4 were the only ones who had two targets: cupola 14, which turned out to be a false target, and casemate 17, which was positioned along the Albert Canal.

During an interview, Helmut Wenzel stated that some of the DFS 230 gliders were over their maximum takeoff weight of 4,630 pounds. This he concluded was “why later some of the tow ropes broke.”

*Assault Force Iron, under the command of Lieutenant Schaechter, was tasked with capturing the Canne bridge intact. The Belgians had wired the bridge with explosives, and when Schaechter’s assault force failed to gain surprise and then had difficulty exiting the gliders, the Belgians destroyed the bridge. Assault Force Iron lost four dead and six seriously wounded.