Defence

Newly established UK unmanned air vehicle manufacturer Dragonfly Air Systems is planning to fly a twin ducted-fan, short-range tactical unmanned air vehicle in late August and has begun constructing a prototype.

The company also hopes to roll out a tilt-wing tactical UAV - designated Highland Darter - later this year, and is separately working on a micro vertical take-off and landing system called Hawker that could be carried in a soldier's backpack.

The twin-ducted fan vehicle - designated Globe Skimmer - will probably make its debut flight at the ParcAberporth range in west Wales, says Dragonfly chief scientific officer Simon Scott.

Concept work on the Globe Skimmer design began three years ago, Scott says. Bournemouth, UK-based Dragonfly was set up last month to develop the concept and prepare it for production. A mock-up of the UAV was displayed at ParcAberporth.

The Globe Skimmer has an underslung vertical fuselage with two engines driving counter-rotating propellers. The engines and fans sit at the top of the fuselage, while the electro-optical/infrared pay­load is suspended at the base, allowing unobstructed 360° coverage.

The twin ducted fans project from the fuselage at right angles during flight, but fold for storage. Each duct is able to independently rotate from a horizontal position in hovering flight to a tilted position to provide forward motion.

The UAV would have an all-up weight of 20kg (44lb), with separate electric- and petrol-powered versions being planned. The electric version will have an endurance of up to 1h, says Scott, while the petrol version would be able to fly for 2h.

The Highland Darter will have a 2.05m (6.7ft) fuselage with an inverted V-tail and small canard near the nose. Wingspan is 2m long with deflected tips.

The propulsion system will comprise two wing-mounted counter-rotating propellers in ducts with additional folding pusher propellers at the rear of the mounts to support transition from hovering to forward flight. The UAV is expected to have a forward speed of 90kt (166km/h).