World War II Weapons That Completely Failed

World War II is considered the deadliest and most destructive conflict in history. Not only were there an incredibly high amount of casualties, both civilian and military, but the physical and economic destruction was astronomical. The war began in 1939 but it wasn't until the attack on Pearl Harbor in 1941 that the United States declared their involvement, battling alongside the Allied Powers until the war ended in 1945.

The Second World War catapulted the United States from a midlevel global power to the leader of the free world, per the National World War II Museum. It was a period of rapid innovation, and industrial growth, and a time that saw the most economic growth in history. The war may have spurred revolutionary advances in fields like radar, propulsion, and nuclear energy that have shaped the postwar era, but the conflict also saw the development of several significant failures in weapons technology. 

Many failed weapons didn't account for the advancement of battle style from static trench warfare to the Blitzkrieg-style combined arms assaults that would characterize the conflict. Nothing illustrates this more than the Cultivator No. 6, designed to burrow toward an enemy line while boring a trench wide enough for a troop of soldiers to follow behind it. This demonstrated how certain weapons are often too bulky for combat use.

Then there was the French Maginot Line, a 300-mile series of fortifications along the eastern border of France, which failed to anticipate the all-terrain battery of bombers and armored vehicles that Germany would amass in the leadup to the war. It was ultimately penetrated in May 1940. Numerous weapons failed due to outdated design thinking, but others, like the Goliath, were too far ahead of their time. This remote control vehicle could carry bombs with up to 100 kg charge but was largely worthless in the field.

To compile a list of World War II weapons that completely failed, 24/7 Tempo reviewed WWII weapons object records from the Imperial War Museum. Weapons and weapons programs that are considered failures are ranked alphabetically. Although some weapons failed due to outdated design thinking, others were too far ahead of their time, like the Goliath, a remote control vehicle that could carry bombs with up to 100 kg charge. Tethered by wires easily cut, the Goliath was largely ineffective in the field, despite being the precursor to modern-day drones and other radio-controlled military vehicles. (Thankfully, not all equipment was a failure. Here are 33 iconic weapons of World War II.)

• Country: Great Britain
• Type of weapon: Two-seater fighter plane with four .303-inch machine guns situated behind the pilot

The Boulton Paul Defiant was designed to allow the gunner to attack enemy aircraft flying alongside or below the plane. While the unusual design allowed RAF pilots to combat dynamic formations of enemy bombers, the Defiant's lack of forward-firing weapons made it vulnerable to conventionally designed fighter planes. The plane's shortcomings were apparent during the Battle of Great Britain when two Defiant squadrons suffered heavy losses and had to be withdrawn.

• Country: Great Britain
• Type of weapon: Cruiser tank

Created in 1939 and designed to speed past gaps in enemy defense lines, the tank didn't have any glaring design flaws, but by the time the Covenanters were delivered in 1941, its 2-pounder gun and 30mm armor were already outclassed. Other defects like engine cooling problems were soon discovered. None of the 1,711 Covenanter tanks produced saw combat duty, but the British army used them for training.

• Country: Great Britain
• Type of weapon: Trench-digging machine

Nicknamed "White Rabbit" or "Nellie," this machine was based on an idea first proposed by Winston Churchill during World War I and was designed to burrow towards an enemy line, boring a trench wide enough for a troop of soldiers to follow behind it. The 130-ton machine proved ill-suited for the combined arms Blitzkrieg-style fighting characteristic of World War II and was retired after a few had been constructed.

• Country: Germany
• Type of weapon: Remote-control vehicle

The Leichte Ladungsträger, or Goliath, was designed to carry explosive devices into buildings, bunkers, and enemy troops and vehicles and then detonate them. The tracked vehicle could carry bombs with up to a 100 kg charge but moved relatively slowly and had long trailing control wires that were vulnerable to being cut. Some 2,650 vehicles were built between 1942 and 1944, but they were largely ineffective in the field.

• Country: Japan
• Type of weapon: Fu-Go Balloon Bomb

The United States was largely invulnerable to air attacks during World War II as they were separated from Axis countries by two oceans. However, this didn't prevent Japan from embarking on an experimental bombing campaign against the United States in the final stages of the war, sending unmanned balloons laden with explosive devices across the Pacific Ocean to release and detonate over American territory.

While 9,000 bombs were launched, few made landfall. The only casualties that resulted from the campaign were six picnickers who accidentally discovered a balloon device in the woods of Oregon in 1945 and made the mistake of trying to move it.

• Country: Japan
• Type of weapon: Pilot-guided explosive missiles

In response to the overwhelming approach of American forces in the final stages of World War II, Japan developed a new strategy of suicide attacks amidst heavy losses. These were known as Kamikazes, pilots used to guide various types of craft – airplanes, motorboats, and crewed torpedos – equipped with bombs as improvised missiles.

Kamikaze warfare resulted in the deaths of about 7,000 allied personnel – and 3,800 Japanese pilots – but the suicide attacks failed to stay the American military's advance, leading historians to question the campaign's efficacy.

• Country: Germany
• Type of weapon: Weapon attachment

The Krummlauf (literally "curved barrel") was developed during World War II, intending to allow the Sturmgewehr 44 assault rifle to fire around corners. However, the intense pressure from firing rounds caused the attachment to distort and wear out rapidly and the bullets frequently shattered upon leaving the Krummlauf. Despite its failure during the war, the concept of a weapon that can fire around corners has been revisited in the design of some modern firearms.

• Country: Germany
• Type of weapon: Heavy bomber

While Germany had been developing a fleet of heavy bombers for strategic bombing, efforts were halted in 1936 after the Luftwaffe's chief of staff, Lt. Gen. Walther Wever, and project head, ironically died in a plane crash. By the time the Luftwaffe was able to deploy a long-range heavy bomber in 1942 to match British and Soviet airpower, Germany had already suffered significant consequences from its lack of a strategic bomber force.

• Country: France
• Type of weapon: Underground fortifications

In the runup to World War II, while Germany was still observing the terms of the Treaty of Versailles – banning the nation from possessing tanks, airplanes, and heavy artillery – France built a 300-mile series of underground fortifications along its eastern border to prevent a surprise attack from Germany as well as a cross-border assault and to defend its territories of Alsace and Lorraine, which lay next to the German border.

The Maginot Line successfully deterred WWI-style ground attacks and would have been a success if it had been used during the First World War where trench warfare was the norm. But by WWII the German army had adopted a strategy of mechanized warfare, with bombers and armored vehicles that could advance on difficult terrain. The Germans crossed into France at a weak point in the Maginot Line in May 1940 and forced a French surrender within six weeks.

• Country: Germany
• Type of weapon: Super-heavy tank

The Panzerkampfwagen VIII Maus was a super-heavy tank designed by Ferdinand Porsche and embodied Hitler's aspiration for an indestructible armored fighting vehicle. First proposed in 1942, development of the tank was slow. While a Daimler-Benz aircraft engine powered the Maus, its 200-ton weight dragged it down, allowing it to reach a top speed of just 12 miles per hour.

Development of the tank was slow and although it was first proposed in 1942, trials didn't start until 1943. It was plagued with consistent mechanical issues, particularly with the drivetrain and even though five Maus tanks were ordered, only two were ever built.

• Country: Germany
• Type of weapon: Small rocket-powered plane

The Messerschmitt Me 163 Komet was powered by a liquid fuel comprised of two volatile substances that would ignite when mixed. Designed to intercept American bombers flying over Germany, the Komet's highly reactive fuel allowed the tiny fighter to reach an altitude of 39,000 feet in just 3.5 minutes and a top speed of over 550 miles per hour. However, it had a flight time of only seven minutes, was difficult to pilot, and accidents caused by mishandling the volatile fuel were common. Numerous pilots were killed during testing and training flights.

• Country: Great Britain
• Type of weapon: Rocket-propelled wheels

According to the Imperial War Museum, the Panjandrum was considered the ultimate invasion weapon and was named after 18th-century nonsense prose. Devised by the British Admiralty's experimental Directorate of Miscellaneous Weapons Development, it was a weapon intended for use against the beach defenses of Hitler's Atlantic Wall.

The mechanism, comprised of two 10-foot rocket-propelled wheels linked by a cylinder filled with explosives, was designed to be launched from a landing craft, speed up the beach, and blast a hole in the sea wall or other concrete barriers. During testing, the wheels frequently malfunctioned or detached, causing the Panjandrum to veer off in random directions, which resulted in it never being deployed.

• Country: Germany
• Type of weapon: Mounted gun

In the build-up to World War II, France fortified its eastern border with the now infamous Maginot Line to prevent an attack from Germany, while Germany devised ways to bypass French defenses. One concept that saw fruition was the Schwerer Gustav, a 1,350-ton, 80cm gun mounted on a railroad car that could launch a 7-tonne shell 29 miles.

Completed after Germany invaded France in 1940, it was used in 1942 against the Soviet city of Sevastopol, making it the largest-caliber rifled weapon ever used in combat. The barrel wore out during the attack and a second Schwerer Gustav gun was produced but never used.

• Country: Great Britain
• Type of weapon: Anti-tank gun

The Smith Gun was designed for the British Home Guard, widely known as the "Dad's Army", a citizen militia stationed within the U.K. It was intended to be a last line of defense against a Nazi invasion and was a weapon that had to be tipped on its side to fire its 3-inch mortar rounds. It was only accurate to about 200 yards and although it went into production in 1941, the weapon developed a reputation for killing those who tried to man it and was never used in combat.

• Country: Great Britain
• Type of weapon: Heavy tank

Designed by the Special Vehicle Development Committee, also known as "The Old Gang," the TOG 1 was long and heavily armored, able to cross trenches and shell-laden terrain, advantages more relevant to the First World War than the second. The committee designed a second prototype, the TOG 2, with more modern weapon attachments like a revolving turret, but the outdated design made the TOG too bulky to be used in war.

• Country: Germany
• Type of weapon: Rocket

The world's first long-range guided ballistic missile carried a one-ton warhead and would ascend to the Kármán line – the edge of space – before descending vertically on its target. Although the V-2 was a technically advanced weapon, it was a wastefully expensive ballistic missile, and even with the successful bombings of London and Antwerp, the total payload delivered by the missile was relatively low in comparison to what a heavy bomber could carry. While 9,000 people were killed in V-2 attacks, more than twice as many slave workers died building the weapons.

• Country: Germany
• Type of weapon: supergun

The Vergeltungswaffe 3 was designed to bombard and destroy London at a rate of 600 shells an hour from an underground complex 100 miles away. The V-3 gun incorporated multiple chambers, whereby secondary gas charges firing along the main barrel gave the shell the extra velocity it needed to reach its target. While 25 gun tubes were positioned and aimed toward London, the V-3 was ultimately destroyed by a 1944 raid before any rounds had been fired.

• Country: Soviet Union
• Type of weapon: Dogs used as anti-tank weapons

Although dogs were used during World War II as messengers or for mine detection from 1941 to 1942, the Soviet Union attempted to use them as anti-tank weapons as well, training them to run toward enemy tanks with explosives strapped to their backs. Many dogs became confused and ran back towards their handlers, blowing them up, or were shot on sight by German soldiers. The Soviet Army quickly abandoned the war dogs program.

• Country: Germany
• Type of weapon: anti-aircraft weapon

The Winkanone, or Wind Cannon, was composed of a large barrel bent upwards, through which a jet of dense, compressed air was shot to damage low-flying aircraft. Trials showed that blasts of high-velocity air could damage ground structures but a wind cannon installed on a bridge over the River Elbe in 1945 had no success.