Flying fan is a spy in the sky

Micro Craft, an aerospace development company based in California, has successfully tested its vertical take off unmanned air vehicle (UAV), a small flying device consisting of a ducted fan that rotates inside a protective cylinder.

The device – which could be employed in a number of surveillance roles – measures 23 centimetres across and weighs in at 1.4 kilograms. The UAV takes off and lands vertically, but flies horizontally by pitching over and developing lift from its duct and optional wing.

The wing – which houses additional fuel reserves – is said to add minimal weight but improves the vehicle performance significantly at loiter conditions.

This, says Micro Craft, allows the UAV to take advantage of the propulsive efficiency of the ducted fan for take-off and landing and the aerodynamic efficiency of the wing during cruise.

A small two-stroke petrol engine drives the fan that provides enough lift to get the craft off the ground and allow it to hover and move from side to side.

To travel at top speed, the vehicle tilts sideways so that the fan points almost horizontally and the airfoil-shaped edges of the duct provides lift.

A remote controller operates the UAV and on-board electronics keep the craft flying, adjusting the speed of the fan and the angle of the control vanes.

The UAV involved in tests carried a video camera that transmitted images back to the ground. Micro Craft anticipate the UAV being employed to support communications relays, or even a laser that would ‘paint’ a target with light to guide in missiles from larger craft.