Original subtitles

If you were told that a company had just invented a robotic dragonfly and it was flying around

today, you might not be impressed. However, CIA developed this "Insectothopter" and

flew it in the 1970s! CIA had developed a miniature listening device that needed a delivery

system, so the Agency's scientists considered building a mechanical bumblebee to carry it.

However, they found that the bumblebee was erratic in flight and scrapped the idea. Then

an amateur entomologist on the project suggested a dragonfly, and this prototype was built.

Crafted by a watchmaker, Insectothopter had a miniature fluidic oscillator to propel the

wings up and down at the proper rate to provide both lift and thrust. A small amount of propellant

produced gas to drive the oscillator, and extra thrust came from the excess gas vented

out the rear. A laser beam provided guidance and acted as the data link for the audio sensor

payload. This is the first flight of the insect-sized unmanned aerial vehicle called Insectothopter.

Flight tests were impressive. Performance measures indicated a range of 200 meters and

flight time of 60 seconds with a 1-gram launch weight. But because control in even a slight

crosswind proved too difficult to overcome, Insectothopter never became operational.