Ranked 66th on the Fortune 500, the Walt Disney Company is among the largest corporations in the United States, and the second largest entertainment company in the world. Valued at over $148 billion, the company owns 5 of the 10 most valuable media franchises including Star Wars and the Marvel Cinematic Universe, operates 14 theme parks and resorts around the world, and owns more than 140 square kilometres of real estate – nearly three times the area of Manhattan. Given its sheer size and wealth, Disney has unsurprisingly exerted outsized influence in a wide variety of fields, from entertainment and transportation technology to city planning, copyright law, and politics. Yet despite building its empire around wholesome, family-friendly entertainment, during the Second World War the House of Mouse threw itself fully behind the war effort, producing a variety of propaganda and training films for the United States government. Less well remembered, however, is Disney’s unwitting contribution to the field of military technology, as one of its wartime films directly inspired a deadly weapon of war. This is the surprising story of the Disney Bomb.

During the Second World War, no nation poured more cubic metres of reinforced concrete than the Third Reich. The Nazi obsession with monumental fortifications extended from the bunkers of the Atlantic Wall stretching from Norway to Spain to the massive U-boat pens at Lorient and La Rochelle to the flak towers defending the skies over Berlin, Hamburg, and Vienna. Symbols of brutality as much as strength, many of these structures were constructed by the some 1.4 million forced labourers of the Nazi Party’s infamous Organisation Todt. In August 1943, Allied reconnaissance aircraft began spotting a number of strange new constructions across occupied France, the purpose of which was at first a mystery. These structures fell into three basic types. The first was a low bunker from which projected a long, shallow ramp supported on concrete pillars. Four of these installations were being built by the Germans at Siracourt, Desvres, Tamerville, and Couville. The second type was a giant concrete dome 71 metres in diameter being built into the side of a disused chalk quarry at Wizernes. A similarly-sized rectangular bunker was also under construction nearby at Éperlecques. The third and final installation was a complex of deep underground tunnels and angled shafts being built at Mimoyecques in the Pas-de-Calais, the closest point in France to the United Kingdom.

These strange installations, as the Allies would soon learn, were the launch sites for a new generation of high-tech weapons systems, which the Germans called vergelstungswaffe – or “vengeance weapons.”

The ramp sites were built to launch the Fieseler Fi-103 – better known as the V-1 or “buzz bomb” – an early cruise missile powered by a crude pulse-jet engine. The bunker was used to store and assemble the missiles while the ramp contained a steam-powered catapult used to accelerate the weapons towards their targets – in this case the Greater London area. Once launched, the V-1 would cruise across the English Channel at an altitude of 1000 metres until a wind-driven propeller in its nose reached a certain number of revolutions. The missile’s elevators would then spring downwards, sending the weapon and its 1-ton explosive warhead diving towards the ground.

The giant dome at Wizernes was designed to launch the more sophisticated V2, the world’s first operational ballistic missile. The V2 was fuelled by ethanol and liquid oxygen, the latter of which boiled off and had to be continuously manufactured. The Wizernes bunker thus incorporated a liquid oxygen plant and an underground workshop where missiles could be prepared and fuelled before being transported via narrow-gauge railway to open-air pads for launch. In this manner dozens of missiles could be launched against London every day. Unlike the V-1, whose distinctive high-pitched buzzing sound could be heard for miles around and which could be shot down by antiaircraft guns or sufficiently powerful fighter aircraft, the V-2 gave no warning of its approach and was essentially unstoppable, descending on its target from the edge of space at twice the speed of sound.

While impressive on paper, the Wizernes bunker was met with skepticism by many German Army officers, who saw fixed sites – however well-fortified – as inherently vulnerable to attack. These officers preferred mobile rocket batteries, which could fuel and launch a V-2 within hours before moving on to a new site, making them extremely difficult for marauding Allied aircraft to track down and destroy. However, all these critics were overruled by Adolf Hitler, who was obsessed with grandiose military constructions.

Finally, the underground fortress at Mimoyecques was built to house the V-3 cannon, a high-velocity gun that used multiple staggered propellant chambers to accelerate a special fin-stabilized shell fast enough to hit London from the coast of France. With a total of 25 gun barrels capable of firing 10 shots a minute, the battery as designed would have been able to bombard its target with up to 600 shells every hour.

Taken together, the Atlantic Wall, U-boat pens, and fortified V-weapons sites presented a formidable obstacle to the Allied war effort, being all but impervious to regular high-explosive bombs. Furthermore, many strategic targets such as railway tunnels and viaducts had proven too small to effectively attack via conventional means. As plans for the invasion of Europe picked up steam, the search began for new kinds of weapons with which to take out these specialized targets.

The solution came courtesy of legendary English engineer Barnes Wallis, who had famously designed the “bouncing bombs” used in Operation Chastise, the famous “dambusters” raid of May 16, 1943 against the three hydroelectric dams in the German Ruhr Valley. To solve the problem of attacking bunkers and other fortified targets, Wallis designed a truly massive bomb he called the “Tallboy”. 21 metres long and weighing five and a half tons, the Tallboy was so huge only one aircraft could carry it: the Avro Lancaster heavy bomber – and then only if two gun turrets and other components were removed to save weight. When dropped from an altitude of 6,500 metres, the streamlined Tallboy accelerated to a velocity of 750 kilometres per hour – nearly the speed of sound – before impacting the ground. This, along with the bomb’s thick, hardened steel casing, allowed it to penetrate up to 5 metres of reinforced concrete before detonating, making it more than a match for even the strongest German bunker. More ingenious still, the Tallboy was designed to be effective even if it missed its intended target. If dropped next to a bunker or railway viaduct, for example, the bomb would penetrate deep into the earth and create a large underground blast cavern or camouflet. The resulting shockwave or ‘earthquake’ effect would shake and undermine the entire structure, often resulting in greater damage than a direct hit.

In July 1943 Wallis designed an even larger earthquake bomb called the “Grand Slam,” which was a full two metres longer and twice as heavy as the Tallboy, with an even thicker casing and greater penetration ability. Like the Tallboy, the Grand Slam was filled by hand-filling the casing with molten Torpex explosive, which could take up to a month to cool and solidify. Due to the expensive, hand-built nature of the bombs, in an emergency crews were instructed to attempt a landing with the bomb still aboard rather than jettisoning it into the sea.

The first Earthquake Bomb attack was carried out on June 8, 1944 against the Saumur rail tunnel in France. Nineteen Royal Air Force Lancasters dropped Tallboys on the target, one of which penetrated the tunnel and detonated inside, knocking it out of action for the rest of the war. As part of Operation Crossbow, the overall Allied campaign against the German V-weapons, on June 19, 24, and 25 RAF Lancasters flew Tallboy raids against the V1 and V2 bunkers at Watten, Wizernes, and Siracourt. The Siracourt bunker received three direct hits while the Watten and Wizernes bunkers were completely undermined by near-misses. These and other Crossbow raids ultimately lead to the  abandonment of fixed V-weapons sites, with all further V1s and V2s being launched from mobile installations.

Later in 1944, Tallboy sorties were carried out against the German Battleship Tirpitz in its anchorage at Tromsofjord in Norway, where it had already survived multiple attacks by conventional bombers and midget submarines – and for more on this, please check out our previous video A Worthy Opponent: the Glorious Death of Hampton Gray. During the last of these attacks – Operation Catechism on November 12 – three Tallboys penetrated the Tirpitz’s deck and into its ammunition magazines, setting off a massive explosion that completely obliterated and capsized the ship.

Operations using the larger Grand Slam began in the spring of 1944, with notable successes including the destruction of the Bielefeld viaduct on March 14 and the Arbergen bridge on March 21, and a March 27 raid on the Valentin submarine pens in Bremen where two Grand Slams and twelve Tallboys penetrated the six-metre-thick reinforced concrete roof, knocking the U-boat factory inside out of commission.

The V-3 cannon bunker at Mimoyecques, however, proved a harder nut to crack, with multiple conventional bombing raids mounted between November 1943 and June 1944 inflicting only minor damage. On July 6, 1944, the RAF launched a Tallboy raid on the site, during which two bombs penetrated and collapsed large sections of underground tunnel, burying over 300 Germans and forced labourers alive. This, combined with the discovery of a serious design flaw in the V3 shells, led to the Germans abandoning the site. However, Allied Intelligence was not aware of this, and the search continued for a weapon capable of destroying the bunker. This culminated in Operation Aphrodite, a US Army Air Force project which involved converting B-17 and B-24 Liberator bombers into  radio-controlled drones, packing them with explosives, and crashing them into the target. The drone was flown most of the way by an onboard pilot and navigator, who bailed out when close to the target, allowing a radio operator in a nearby mothership to guide it the rest of the way. Two Aphrodite missions were flown against Mimoyecques, the first on August 4, 1944. Pilot Lt. Fain Pool and navigator Sgt. Philip Enterline successfully bailed out, but the radio control operator lost control of the drone and it spiralled into the ground short of the target. A second attempt was made on August 12, but shortly into the mission an electrical fault caused the drone’s explosives to detonate prematurely over the Blyth Estuary in England, killing Lieutenant Wilford Willy and Joseph P. Kennedy Jr, elder brother of future American President John. F. Kennedy. In total 14, Aphrodite raids were attempted against various targets, but most were failures, leading the USAAF to abandon the project. Attacks against Mimoyecques ended when Allied ground forces finally overran the site in September 1944.

While the Tallboy and Grand Slam bombs proved incredibly effective in combat, they suffered from a number of limitations. Their penetration ability, being directly tied to impact velocity, was limited by gravitational acceleration and the maximum altitude from which they could be accurately dropped. They were also extremely heavy, severely limiting the aircraft types that could carry them and the maximum speed and range of said aircraft. Strangely, an intriguing solution to these problems would come not from the mind of an engineer, but from the House of Mouse.

By late 1941, Walt Disney Animation Studios was well on its way to becoming an entertainment juggernaut. The four animated feature films the studio had produced up to this point – Snow White and the Seven Dwarfs, Pinocchio, Fantasia, and Dumbo – proved wildly popular with audiences and revolutionized the film industry. But this seemingly unstoppable momentum came to a screeching halt on December 7, 1941 when the Empire of Japan attacked Pearl Harbour and the United States entered the Second World War. An avowed patriot, Walt Disney halted all current film productions and effectively handed his studio over to the U.S. Government. Walt Disney studios would produce hundreds of short films in support of the war effort, including training films such as Stop That Tank and propaganda shorts such as Education for Death and Der Führer’s Face, the latter of which depicted Donald Duck as a beleaguered citizen of the Third Reich. Between 1941 and 1945, the studio released only four feature-length animated films: Bambi, which was already well into production before the war started; Saludos Amigos and The Three Caballeros, anthology films aimed at keeping Latin American nations on the side of the Allies; and perhaps the strangest entry in Disney’s animated canon: Victory Through Air Power. 

Released on July 17, 1943, Victory Through Air Power was based on the book of the same name by Russian-American aviator and aircraft designer Alexander de Seversky. The one-hour film featured a comedic animated retelling of the history of military aviation, intercut with live action segments of Seversky explaining his theories on strategic air power. While many of Seversky’s ideas would later be disproven – especially the notion that a well-armed bomber without fighter escort would always get through to its target – the film was nonetheless instrumental in convincing the U.S. Government to adopt a policy of long-range strategic daylight bombing against Germany and Japan.

Equally influential was a sequence in which aircraft are shown dropping bombs fitted with rocket motors, allowing them to accelerate faster than gravity and penetrate U-boat pens and other fortified targets. At the time, no such weapon actually existed, the concept being entirely the product of a Disney animator’s imagination. But for one Captain Edward Terrell of the Royal Navy Volunteer Reserve, such a weapon was just what the Allied air forces needed to defeat heavy German fortifications. In September 1943, Terrell began developing a weapon inspired by the fictional rocket bunker-buster, which soon became known as the “Disney Bomb” or “Disney Swish.” The weapon, officially designated the 4500 lb Concrete Piercing/Rocket Assisted Bomb, consisted of a 28cm diameter, 5-metre long hardened steel casing packed with 230 kilograms of high explosives and fitted with nineteen 3-inch cordite rocket motors. These motors would ignite around 30 seconds after release, burning for three seconds and accelerating the bomb to 1,590 km/hr or around 1.3 times the speed of sound. This allowed the Disney Bomb to penetrate up to 5 metres of reinforced concrete – roughly the same as the Tallboy and Grand Slam but for less than half the weight, allowing multiple Disney Bombs to be carried by a single aircraft.

Though designed by the British, the Disney Bomb was only ever used operationally by the USAAF, with B-17 bombers of the 92nd Bombardment Group being specially modified to carry it. Two bombs were carried per aircraft on racks slung under the wings, as they were too long to fit in the aircraft’s bomb bay. Initial testing was conducted near Southampton and on the captured V-2 bunker at Éperlecques in France. Of the four bombs dropped on the bunker, two hit their target, and the resultant damage was judged sufficient for the weapon to be approved for combat use.

However, the Disney Bomb saw only limited service before the war ended, with 158 being dropped on four combat missions against the torpedo boat pens at IJmuiden [Ee-mwee-den”] in the Netherlands, the Valentin U-boat pens near Bremen, and fortified targets around Hamburg. Further evaluation took place immediately after the war as part of Project Ruby, with Disney Bombs as well as Tallboys, Grand Slams, and Amazon bombs – American copies of the Grand Slam –  being dropped on various targets such as Heligoland Island, the Éperlecques Bunker, and the Valentin sub pens. Results of these tests were unfortunately mixed. While the Disney’s penetration ability was roughly on par with the Tallboy and Grand Slam, it carried a much smaller explosive charge, limiting the damage it could do after penetrating. This small charge also meant that unlike the larger earthquake bombs, the Disney Bomb needed to hit its target directly to be effective. This was a something of a problem given the bomb’s poor accuracy, the result of unreliable rocket motor ignition and limitations of 1940s bombsight technology. For these reasons, the Disney Bomb was judged to be of marginal usefulness and quickly removed from the Allied arsenal. The general concept, however, was not abandoned, and several modern air-dropped munitions such as the French Matra Durandal anti-runway bomb use rocket assistance to increase terminal velocity and penetration. Though an obscure and ultimately unsuccessful weapon, the Disney Bomb remains a curious and unique example of the inspirational power of film and of life imitating art.

If you liked this article, you might also enjoy our new popular podcast, The BrainFood Show (iTunes, Spotify, Google Play Music, Feed), as well as:

• A Brief History of the “Happiest Place on Earth”
• From Oswald the Rabbit to Mickey Mouse
• The Secret Club Inside Disneyland Where You Can Buy Booze
• What Happened to Huey, Dewey, and Louie’s Parents?