Almost all of us have wished at one time or another to be a fly on the wall-but nobody wants to get swatted. A safer option might be to command a fleet of intelligent flies that could seek out and report critical information while we stay safely removed from danger. With that idea in mind, engineers at MIT's Lincoln Laboratory are now developing a micro air vehicle-a semi-autonomous spy plane small enough to hold in the palm of your hand.

The idea of producing the world's first miniature intelligence-gathering plane was proposed three years ago at Lincoln Lab, where researchers sought a way to provide direct access to reconnaissance data for soldiers serving in small military units, such as those deployed in urban settings. They envisioned a portable surveillance system that could quickly inform soldiers of imminent, unseen dangers. In urban areas, for instance, such a system could enable soldiers to "see over the hill and around the corner," says William R. Davis, who manages the Lincoln Lab micro-air-vehicle program. Advanced versions might sniff out nuclear, biological, and chemical weapons in hostile terrain, assess battle damage, or monitor hostage crises or Waco-style standoffs.

Based largely on concepts outlined at Lincoln Lab, the Defense Advanced Research Projects Agency (DARPA) launched a $35 million program this year to develop prototype micro air vehicles, soliciting preliminary proposals from industry and academia. Organizations competing for funding include university laboratories such as Georgia Tech Research Institute (GTRI), aerospace companies, and small businesses.

At the same time, DARPA has provided initial funding to Lincoln Lab to develop a fully functioning prototype, which researchers expect to complete within three years. Weighing two ounces and measuring less than six inches in length and width, the prototype vehicle will fly at 20 to 30 miles per hour, operate within a radius of up to 3 miles (the limit relates to the expected range of the vehicle's communication system), and remain airborne for up to an hour. It must also have reconnaissance and navigational capabilities.