Silent witness

Later this month the West Midlands Fire Service will take delivery of a battery-powered, unmanned spy drone that can hover quietly, perform a tight turn and take off from an area the size of a dustbin lid.

The service plans to use the diminutive vertical take-off and landing (VTOL) craft, the MD4-200, to get a bird’s eye view of buildings that are on fire and help co-ordinate the response to major incidents, such as motorway accidents. The Environment Agency, as well as police forces including Hertfordshire, Dorset, Cheshire and the Met, are also said to be interested in trialling the device.

The aircraft is the brainchild of German engineer Udo Juerss, a former Ford development engineer who left the car giant to set up his own company, Microdrones, four years ago.

Made entirely from carbon fibre reinforced plastics, the vehicle weighs 900g and can carry a payload — usually a digital camera — of up to 200g. Able to fly for 20 minutes at a speed of around 10m/s, the craft has flown at altitudes of almost 6,000ft (1,800m). However, civil aviation regulations are likely to limit its operating altitudes to around 800ft.

The vehicle’s rotors are driven by four synchronised, brushless motors, which give the drone performance characteristics comparable with a helicopter. During operation, an array of onboard accelerometers, gyroscopes, and sensors measure air pressure, humidity, and temperature and feed back valuable flight information to a base station on the ground.

Juerss said the system is so easy to use that it can be taken out of the box and flown by a novice within a few minutes. He added that the vehicle’s light weight also makes it exceptionally safe, and if a user’s finger happens to get in the way of one of the 7g flexible rotor blades it is highly unlikely to cause any injury.

To operate the craft users can choose from three different guidance modes. At its simplest level it can be operated by radio control, with GPS holding it in position if the user does nothing. It can also receive its commands from a computer via a base station on the ground. But perhaps most excitingly, and this is where it really begins to compete with the considerably pricier military UAV systems, it is also capable of autonomous navigation via waypoint.