if you are a soldier then better do not ignore birdlike flying devices while waiting in ambush. These tiny flying machines may be enemy's tool to locate your hiding place. And ultimately you may land up in their captive. Researchers in the us are developing tiny robot-controlled aircraft that would mainly be spurred by military interest. These devices would be so small that they could fit into the palm of a person's hand.

The intelligence-gathering planes are expected to provide small military units direct access to explore data that could help them in battling any enemy just over a hill or one engaging them in street-to-street fighting in a city.

These microflyers can also find diverse applications in fields such as guiding fire and rescue operations, monitoring traffic, surveying forests and wildlife, and keeping watch in border areas. Engineers say that designing such devices are not that easy. According to William Davis, manager of the microflyer program at the Massachusetts Institute of Technology's Lincoln Laboratory, usa , if such small planes are developed, all the rules change and everything becomes challenging.

For such small planes, normal aerodynamic rules do not apply. The tiny aircraft will have to operate in an environment more common to small birds and large insects than that of large aircraft. As these devices have small wings, they will have reduced lift and decreased propeller efficiency, say engineers.