Boeing has created an unmanned electric air vehicle prototype that it will use to test and evolve autonomous cargo delivery vehicles of the future.

Showcased at CES in Las Vegas last week, the "multi-copter" prototype is strong enough to transport cargo weighing up to 500 pounds (approximately 227 kilograms).

The prototype is powered by an environmentally-friendly electric propulsion system and is outfitted with eight counter-rotating blades, which allow for vertical flight.

Weighing 747 pounds (339 kilograms), the aircraft measures 15 feet long (4.57 metres), 18 feet wide (5.49 metres) and four feet tall (1.22 meters).

The project was led by Boeing HorizonX – a subdivision of the Chicago-based aerospace company that was set up to search the world for startups offering revolutionary ideas.

Working in collaboration with the technicians and engineers at Boeing Research & Technology, the electric vertical-takeoff-and-landing prototype was designed and developed in less than three months.

It has subsequently successfully completed initial flight tests at Boeing Research & Technology's Collaborative Autonomous Systems Laboratory in Missouri.

"This flying cargo air vehicle represents another major step in our Boeing eVTOL (electric vertical-takeoff-and-landing) strategy," said Boeing chief technology officer Greg Hyslop. "We have an opportunity to really change air travel and transport, and we'll look back on this day as a major step in that journey."

Boeing also notes that the prototype complements an eVTOL passenger air vehicle prototype aircraft which is in development by Aurora Flight Sciences – a company acquired by Boeing late last year.

"Our cargo air vehicle (CAV) prototype builds on Boeing's existing unmanned systems capabilities and presents new possibilities for autonomous cargo delivery, logistics and other transportation applications," said Steve Nordlund, Boeing HorizonX vice president.

"The safe integration of unmanned aerial systems is vital to unlocking their full potential. Boeing has an unmatched track record, regulatory know-how and systematic approach to deliver solutions that will shape the future of autonomous flight."

While Boeing isn't the first company to create vehicles for drone delivery, its prototype is much bigger and more powerful than designs already unveiled by the likes of Amazon, UPS, and Google.

The presentation of the UAV prototype at CES follows on from the unveiling of Boeing's stingray-like MQ-25 drone last month. Created as Boeing's entry to a US Navy competition, the MQ-25 will be used for refuelling fighter jets mid-air.

Other large-scale UAV prototypes to be developed in recent years include the world's first passenger-carrying drone, which was unveiled at CES 2016, and the world's smallest flying car, last year.