Although there are now a few different crop-spraying multicopter drones, fixed-wing drones are faster and have a longer battery range. That’s where the recently US-certified autonomous electric Pelican crop duster comes into the picture.
Developed by Oakland, California-based startup Pyka, the Pelican is claimed to be much cheaper and easier to use than combustion-engined, human-flown, fixed-wing crop-spraying aircraft. Additionally, because it is unpiloted, there’s no risk of a pilot being killed or injured in a crash.
The drone itself is 20 feet (6 m) long, has a 38-ft (11.6-m) wingspan, carries a spray payload of up to 625 lb (283 kg), and can take-off and land within a space of just 150 ft (45.7 m). Thrust is provided by three 20-kW electric motors – two on the wings, one in back – delivering a cruising speed of 90 mph (145 km/h). Those motors are powered by a lithium-polymer battery pack, a full charge of which is claimed to be good for a flight range of 70 miles (112 km).
Plans call for the final version of the Pelican to utilize its 3D mapping and path planning systems to establish the location and boundaries of the target field, and to identify obstacles in and around that area. This data (currently gathered by ground crews) is used to create a flightpath consisting of successive passes over the field, which the aircraft subsequently follows. It not only cruises autonomously but also takes off and lands on its own, reportedly never varying from its preprogrammed path by more than 1 meter (3.3 ft).
According to Pyka, the Pelican can spray up to 135 acres (54.6 hectares) of land per hour – that figure is based on a spray rate of 2 US gallons (7.6 l) per acre, and includes filling time, turn-arounds and battery swaps.
One of the company’s earlier prototype aircraft, the Egret, has already been tested on crops in New Zealand. On Oct. 1st, though, the Pelican was granted a special airworthiness certificate by the US Federal Aviation Administration. This will allow it to be demonstrated at American farms, where crews will be trained in its use.