A Brief History of Unmanned Aircraft From bomb-bearing balloons
to the Global Hawk. - By Ed Darack - AirSpaceMag.com, May 18,
2011 NASM (SI 2003-6574) The first truly intercontinental weapon
system, Japan's “Fu-Go” balloons were designed to cause
widespread forest fires and damage to North American cities,
civilians, and croplands during World War II. The hydrogen-
filled balloons measured 30 feet in diameter. Each carried a
payload of 32 paper sandbags, two incendiary devices, one small
bomb, and an altitude regulation mechanism. Launched from Japan,
the balloons would rise to roughly 30,000 feet, where they would
hitch a ride on the jet stream and travel at speeds of up to 120
miles per hour eastward. As hydrogen leaked out slowly, the
balloon descended. At 25,000 feet, the altitude regulation
system would drop one of the sand bags, causing the balloon to
rise back to 35,000 feet. This continued until just the
incendiary devices and bomb remained; then they too were dropped
on the last dips to 25,000 feet. T