How Bats Almost Became America’s Strangest Secret Weapon

Warfare has produced plenty of strange inventions, but few ideas were as bizarre as America’s plan to turn bats into flying weapons. During World War II, the U.S. explored a proposal to attach tiny incendiary devices to bats and release them over enemy cities, where they would roost in buildings before the devices ignited.

The plan sounds like something out of fiction, but it was a real military experiment. It was also far from the only unusual weapon humans have tried to use in combat. From oddball firearms and awkward war machines to animal-based weapons and experimental bomb delivery systems, military history is filled with ideas that were clever, desperate, dangerous, or completely impractical.

To highlight some of the strangest examples, History Computer reviewed historical and military sources on unusual weapons of war. These entries show just how far nations have gone in search of an advantage, and why some weapons are remembered less for their success than for how unbelievable they seem today.

• Origin: United Kingdom
• Developed: 1943-1944

The Panjandrum, named after a whimsical term coined by British actor and playwright Samuel Foote in the mid-18th century, looked like something out of a cartoon. It had two large, 10-foot-diameter wooden wheels with metal treads, revolving around a steel drum packed with explosives. Cordite rockets attached to the wheels' inner rims were intended to propel the contraption into concrete fortifications, where the explosives would then create an opening wide enough for tanks to pass through. During tests, however, the rockets frequently detached and flew off unpredictably, making the entire device uncontrollable. In its final test, the Panjandrum veered dangerously towards observers, nearly hitting a photographer, before crashing, and falling apart. Consequently, the project was quickly canceled.

• Origin: Soviet Union
• Developed: 1941-1943

Dogs have been used in warfare since ancient times for various roles such as carrying messages, sounding alarms, tracking enemies, and even engaging in attacks. In 1930, the Soviets began training dogs for a different tactic: carrying explosives to be detonated remotely upon reaching their targets. These "anti-tank dogs" were first used in significant numbers in 1941 against German tanks. However, their effectiveness was limited, as they had been trained on stationary vehicles and were hesitant to confront moving tanks. By 1943, their use had mostly been discontinued, though reports suggest that anti-tank dogs were still being trained under the Russian Federation as late as 1996.

• Origin: United Kingdom
• Developed: 1941

Documents discovered in 1996 revealed that a covert U.K. government organization called the Special Operations Executive developed a wide array of deadly James Bond-style gadgets during WWII. One of their weirder inventions was the exploding rat. Real rats were collected (by an SOE officer pretending to need them for lab experiments), killed, skinned, filled with plastic explosives, and sewn up. The idea was that infiltrators would distribute the rats near boilers in industrial facilities, where workers would spot them and toss them into the fire – blowing the place up. The scheme failed, but had an unintended consequence: The Germans intercepted a shipment of prepared rats before they could be used, and the discovery unnerved them so much that they expended valuable resources on hunting for similar rats they feared might already have been distributed.

• Origin: Germany
• Developed: 1944

The Krummlauf ("crooked run") was a German attachment for the STG 44 assault rifle designed to allow soldiers to fire around corners using a periscope-like sight. The Krummlauf came with barrels bent at 30, 45, 60, and 90 degrees, though only the 30-degree version saw any significant production. Unfortunately, the Krummlauf-equipped rifles were largely ineffective. The pressure inside the curved barrel caused it to wear out after just a few hundred rounds, and bullets often shattered when they rounded the curve. Ultimately, the Krummlauf proved to be a costly and impractical endeavor for the Germans.

• Origin: U.S.A.
• Developed: 1942

In another chilling example of using animals for destructive purposes, the U.S. developed a plan involving bats. A large bomb was designed with numerous compartments, each containing a hibernating Mexican free-tailed bat equipped with a timed incendiary device. The bomb, released with a parachute, would open mid-air to release the bats, which were expected to find shelter in nearby buildings where they would ignite at a preset time. This method could have been particularly devastating in Japan, where many structures were made of wood and paper. However, after a test accidentally ignited an army airfield in New Mexico, the project was taken over by the Navy but was eventually canceled due to delays in its development.

• Origin: U.S.A.
• Developed: 1950s

Extensive secret U.S. studies of the possible effects on soldiers in the field of various drugs, including LSD, began in the mid-1950s at the Edgewood Arsenal in Maryland. One result of this research was the development of softball-sized artillery shells filled with a substance called 3-Quinuclidinyl benzilate – BZ for short – an odorless powder known to cause delirium and hallucinations. The idea was to disorient enemy soldiers so that they were incapable of fighting. The Army tested the shells, but their effects proved to be too unpredictable, and they gave up on the idea.

• Origin: Iraq
• Developed: 1988-1990

Big Babylon was a supergun developed at the behest of Saddam Hussein by a Canadian engineer named Gerald Bull. It was designed to shoot projectiles into space from which they could presumably be directed back to earth, aimed at targets in, for instance, Iran or Israel. It was impractical because it was immovable and its firing would have revealed its location to enemies. Work on the project ceased in 1990 after Bull was assassinated, perhaps by the Mossad.

• Origin: U.S.A.
• Developed: 1994

"Make love, not war" could have been the motto for a peculiar concept developed by a U.S. Air Force research lab. The proposal involved releasing sex pheromones over enemy troops from a mid-air bomb, with the hope that it would induce sexual attraction among soldiers, leading them to seek romance rather than engage in combat. This idea, informally called the "gay bomb," aimed to turn soldiers away from fighting. Other related concepts included dispersing substances that would cover combatants in various unpleasant odors, potentially disorienting them and making them easier to find. However, since no pheromone has ever been proven to directly influence sexual behavior, the "gay bomb" was never produced, and the other ideas didn't fare much better.

• Origin: United Kingdom
• Developed: 1940-1943

These were anti-tank explosive devices with a sticky exterior, meant to adhere them to their target vehicles. The grenades were widely used in the early years of World War II, with some success, but they didn't stick to surfaces coated with dirt or mud – as tank exteriors tended to be – and, worse, they sometimes got attached to the clothing of the soldier who was attempting to deploy them. By 1943, they had largely fallen out of use.

• Origin: Ancient Greece
• Developed: 213-212 B.C.

It might sound like something out of "Star Wars," but the great Sicilian-born Greek mathematician, scientist, and inventor Archimedes is said to have created a devastating heat ray by assembling a bank of mirrors that focused sunlight onto Roman ships during the Siege of Syracuse, causing them to burst into flame. Some modern scientists are skeptical, and attempts to reproduce the effect have had mixed results – though some did in fact start conflagrations on dummy ships. At the very least, historians agree, the mirrors would have blinded sailors and possibly disoriented them, giving the Greeks a tactical advantage.

• Origin: Japan
• Developed: 1944-1945

Developed by the Imperial Japanese Army's research institute, these were paper balloons filled with hydrogen gas and equipped with incendiary devices. Thousands were launched from Japan's western coast to travel via the Jet Stream towards the U.S., with even their creators estimating that only about 10% would successfully make the crossing. The intent was to ignite forest fires in heavily wooded areas, causing panic and demonstrating Japan's military reach. However, because they were launched in winter and early spring when the forests were damp, even the few that made it across had little effect. Remains of the balloons were found in 17 states, as far east as Michigan, and in the then-territories of Alaska and Hawaii, as well as in parts of Canada and Mexico. Tragically, one fire balloon claimed American lives when a minister, his pregnant wife, and five Sunday School students encountered an unexploded balloon in the forest near Bly, Oregon. It detonated, killing them all.

• Origin: Ancient Greece, etc.
• Developed: 3rd century B.C. and later

Perhaps the cruelest of all military uses of animals were pigs coated in resin or pitch, set aflame, and sent towards the enemy. The earliest account of their use comes during the siege of Megara, in Greece, in 266 B.C. The Macedonian forces attacking the town had an army of war elephants, and the approach of the burning pigs, squealing in pain and fear, terrorized the pachyderms, some of whom trampled Macedonian soldiers to death in their panic. Other Greeks and also the Romans reportedly used the technique with success in subsequent battles.

• Origin: U.S.A.
• Developed: 1863

In a latter-day tactic reminiscent of the heat ray perhaps devised by Archimedes in ancient times, Union forces besieging the Confederate-held Fort Wagner at the mouth of Charleston Harbor repurposed calcium floodlights, also known as limelights, from their use as stage lighting. The intense beam these lights throw were focused at the fort during the night, simultaneously illuminating it for the benefit of Union artillery and temporarily blinding the Rebels.

• Origin: U.S.A.
• Developed: 2005

A canine-looking military robot called BigDog was developed by America's Defense Advanced Research Projects Agency (which also came up with the ARPANET, the precursor of the internet). It wasn't a weapon strictly speaking but was meant to function as an automated pack animal, able to traverse uneven terrain while carrying weapons and other materiel. The problem was that it was powered by an internal combustion engine, which was judged to make too much noise for battlefield use, and BigDog was discontinued.

• Origin: Russian Empire
• Developed: 1914-1915

This bizarre armored vehicle, built for tsarist forces in pre-revolutionary Russia, didn't use treads like conventional tanks but instead ran on three wheels like a tricycle – the front two nearly 30 feet in diameter and the third only five feet high. Each of the larger wheels was powered by a Maybach engine taken from a captured German plane. Development of the tank halted in 1915 when it became stuck in soft ground during a test, and not even its powerful engines could free it. Two of the tank's creators were determined to fit it with a more powerful engine and continued to work on it even after the project was canceled. They never managed to free it, and after the Russian Revolution of 1917, it was forgotten and left to rust until 1923 when it was taken apart and sold for scrap.