Even as the Soviet Union’s terrified tank dogs were hiding from the Panzers, and just before B F Skinner’s poor pigeons were being made redundant, a new animal was emerging as a potentially more successful weapon. Dental surgeon Dr Lytle S Adams had just returned from a visit to the Carlsbad Caverns in New Mexico when he heard the shocking news of the attack on Pearl Harbor. With thoughts of bat-infested caves fresh in his mind, mixed with feelings of patriotism and retaliation, an idea began to take shape. And the more he thought about it, the more he realised what was missing from the US Army’s arsenal: the Bat Bomb.
Unsure of the specifics but convinced of its genius, Adams wasted no time in sharing his idea in a letter direct to the White House, imploring the Government to explore the possibilities of Bat Bombs. His letter reached the desk of the Commander-in-Chief. An encouraging if cryptic memo from President Roosevelt to his coordinator of information, William J Donovan followed: ‘This man is not a nut. It sounds like a perfectly wild idea, but is worth looking into.’ Praise indeed.
After being passed to the National Defence Research Committee (NDRC), the bare bones of the idea were fleshed out, and by 1942, the basic plan was as follows: to release very large numbers of bats, each carrying a small incendiary time-bomb, over an enemy city from high altitudes in the dead of night. The incendiary devices would be timed to ignite after the bats had descended to lower altitudes and taken shelter for the day in buildings, factories, and warehouses, spreading fire and havoc about the city. Nervous animal-lovers had their minds put at ease by the Chemical Warfare Service’s insistence that the bats, having reached their desired roosts, would ‘gnaw through the string and leave the bombs behind’.
The next step was to find the perfect bat. After the Mule-eared Bat and the strong Mastiff Bat had both been ruled out due rarity, Adams and his research team decided on the abundant, if puny, Mexican Free-tail Bat. Despite its tiny size, tests showed that the little bat could fly fairly well while carrying an 18 gram explosive.
Once captured, the bats were placed in refrigerated trays, as cooling them forced them into a state of hibernation in which they were docile and did not need to be fed. Initial problems began to surface when technicians experienced difficulty attaching bomb to bat. Often, when affixing the surgical clip and string to the loose, delicate skin on the bat’s chest, the skin would tear, too flimsy to carry the weight. From here, things only got worse. On 21 May 1943, those bats successfully laden with dummy bombs were packed into hollow cases and dropped from a height of 5,000ft. Sadly, at the critical moment, the chilled bats did not wake up and all fell comatose to their deaths.
Further secret tests from the new auxiliary airfield at Carlsbad followed with similarly disappointing results. When the bats did awaken, their cargo meant that they could not fly very far. Many, luckily only carrying dummy bombs, were later found underneath and in the roof of the building from which the tests were being conducted.
By this time, 6,000 bats had been used in the experiments, and time and money expenditure were rising. To quell mounting doubts, the developers released a report stating that a better time-delay fuse, a more effective parachute-guided container, and new clips had been designed for further tests. But after a particularly disastrous test under the sceptical watch of military top brass, involving escaping bats, the incineration of most buildings at the Carlsbad auxiliary airfield, and the destruction of a large portion of the test material, the army had had enough.
The navy had marginally more success with the idea in December 1943 with tests using improved bomb shells. However, when they discovered that a fruitless $2 million had already been spent on a project which would take until mid-1945 to complete, testing and development were cancelled. The crest-fallen but stubborn Adams later maintained,
‘Think of thousands of fires breaking out simultaneously over a circle of 40 miles in diameter for every bomb dropped. Japan could have been devastated, yet with small loss of life.’