The next time a small bird perches on a ledge outside your window, beware; it could be a surveillance device! David Cylinder, a researcher at New Jersey’s Princeton Plasma Physics Laboratory (PPPL), is creating innovative, bird-like airframes for micro-aircraft vehicles that could carry sensors for intelligence gathering and radar jamming. Cylinder’s creation is part of his work with the Naval Research Laboratory to develop autonomous vehicle systems for use in various military applications.

The aircraft would range from bug- to bird-size, weigh less than a pound, and have wingspans of less than a foot. The Navy and the Marines would ultimately use the aircraft to carry electronic, acoustical, magnetic, nuclear, chemical, motion, and other types of micro sensors and secure transmitters. For surveillance purposes, the vehicles could resemble an insect or a bird.

Cylinder designed one model, Samara, which looks like two winged seeds that counter-rotate. The name hails from the samara seed—such as that of a maple tree—which has a wing like a single-bladed rotor. His inspiration for the Samara model? Hummingbirds.

"I thought about the Samara design while I was in the backyard watching a hummingbird. When they hover, they flap their wings like reversing propellers because without a rotary joint, the wings cannot go all the way around like a helicopter. The Samara's wings rotate slightly off kilter, so that they can go all the way around. One wing just passes over the top of the other," he noted.

Cylinder, who has a lifelong passion for birds and model planes, observed, "Nature has the perfect flying system—birds. They have every piece of apparatus to survive and still can fly thousands of miles without refueling. We are nowhere near duplicating this…but maybe we can learn to design better small aircraft from the birds."

Cylinder's models, made from balsawood reinforced with carbon fiber and a smattering of plastic, are extremely delicate. Fashioned from his designs, he fabricates them with off-the-shelf parts and raw materials. Powered by rubber bands or small electric motors, the models can actually fly. Cylinder's initial tiny demonstration model has a 6-inch wingspan. The next remote-controlled prototype will be more practical, with a 14-inch wingspan. "In the future, we will be able to build whatever size to fit the need," said Cylinder.

For more information, contact Patti Wieser at (609) 243-2757, pwieser@pppl.gov.