Bats Over Tokyo
January 14, 2008
During this week in January 1942, President Franklin Delano Roosevelt received a proposal from a dentist in Pennsylvania that would launch one of the most bizarre adventures in the history of the United States Army and its air corps, Project X-Ray. In a letter dated January 12, Dr. Lytle S. Adams envisioned American airplanes over Japan unleashing a swarm of bats, each loaded with a small incendiary bomb. The miniature bombers and the fires they would set would terrorize the Japanese people and burn down their cities, though the "innocent could escape with their lives." Dr. Adams had political connections with the President's wife, and through her auspices, FDR penned a note to his advisers that literally read, "This man is not a nut. It sounds like a perfectly wild idea but is worth looking into."
Armed with that note, and his own unbridled enthusiasm, Dr. Adams overwhelmed scientific opposition to his scheme, and by the summer of 1942 the Army Air Forces and Chemical Warfare Service were fully engaged in its support. While Dr. Adams traveled around the American southwest in his battered Buick heading a team looking for a dependable supply of Mexican Free-tailed Bats, the National Defense Research Committee assigned Dr. Louis Feiser to develop an appropriate incendiary munition. Tests showed that the animals could carry up to eighteen grams of payload, more than their own weight. Feiser eventually came up with a 17.5 gram napalm device that could be sewed on a bat and ignited by a timer. When "Doc" Adams' searchers found a local expert on bat guano in Bandera, Texas, he led them to caves containing the world's largest known colony of the targeted species, with numbers in the millions.
The ingredients for Project X-Ray were in place. But some problems remained. For instance, the bats were not very cooperative about being loaded up with the incendiaries. The solution was to freeze them into hibernation, but then they did not thaw out in time when dropped from the aircraft. That difficulty was overcome with a special parachute delivery device. The hibernating bats were placed in layered containers resembling egg crates, which popped open as the large container floated down. As they awoke, they would fly away and roost. Tests showed that the system produced ten times more fires than an equivalent load of regular fire-bombs.
A photo opportunity gone awry at Carlsbad Auxiliary Army Airfield in 1943 also proved that the bats could start nasty fires. Some of the hibernating bombers on display for a training film woke up and burned down most of the buildings! That debacle, a high and a low for the program, led the Army to drop support for Project X-Ray, but the Navy then stepped in to assume responsibility. However, by the spring of 1944, they also decided to discontinue it, based on a large number of "uncertainties" about its utility. So we shall never know if these little raiders could have indeed changed the course of the war - or if the whole idea was simply batty!