Ever since Jeff Bezos raised the idea of using drones to deliver Amazon packages, people have been wondering when they’ll see an airborne vehicle show up on their doorsteps. So far we’ve seen quite a number of companies working on delivering medical supplies, like Zipline, UPS and DHL. Most ordinary consumers, though, have yet to receive packages carried by drones.

In China, DHL is starting to experiment with commercial airborne deliveries.

Operating out of a DHL service center in Dongguan -- a tech manufacturing hub between Shenzhen and Guangzhou -- the project delivers cargo weighing up to 11 pounds within a distance of 5 miles. The mini aircraft are supplied by Ehang. The drone maker is perhaps best known for its elaborate drone light shows and its effort to build a self-flying vehicle carrying human passengers.

Dramatic lift-off. (Picture: DHL)

Ehang’s drones for DHL won’t actually land on people’s porches. Instead, they travel between smart outdoor lockers, picking up and dropping off packages that are then carried by DHL workers to their final destinations.

The approach, which seems to be more practical in areas where people live primarily in apartment buildings, was also adopted by Chinese food delivery app Ele.me last year.

(Abacus is a unit of the South China Morning Post, which is owned by Alibaba, owner of Ele.me.)

Advocates of drone deliveries claim they are faster and better for the environment compared with ground deliveries. DHL says it’s able to cut delivery time from 40 minutes to 8 minutes using drones, and it’s looking to identify new routes.

But while it’s one thing to operate drone deliveries on a short, predictable path, it’s another to scale these services up. That presents many more challenges.

One major challenge is that drones have an annoyingly short battery life. DJI’s latest Mavic 2 series, for instance, lasts only a little more than 30 minutes per charge. That means unless battery life improves, companies will have to cover the areas they serve with plenty of service stations.

The next challenge is safety. You don’t want a drone to fall on someone’s head. That might be easier to avoid in rural neighborhoods, but much harder in crowded urban areas packed with pedestrians, buildings and power lines.

Noise is another concern. As anyone who’s ever flown a drone knows, those propellers are loud.

Tracking a drone. (Picture: DHL)

DHL says their drone flights are automated and monitored in real time through GPS signals. And Ehang says the project has the blessing of China’s aviation authorities. The country updated its drone regulations last year, setting off a spate of drone delivery trials by Chinese giants like JD.com and S.F. Express.

Despite the challenges, China isn’t the only country encouraging drone delivery innovation for consumers.

Australia gave Google’s drone spinoff Wing the greenlight in April to launch an air delivery service in Canberra, starting with three suburbs. Local businesses like cafes and pharmacies can send products to customers, “straight to their doorstep.” In the US, Wing also received government approval to start delivering small packages in rural Virginia.

As for Amazon? Prime Air has already missed Bezos’ original plan to see the company’s drone delivery service launch by 2018. It has run a couple of demos over the years, though, and appears to be still be in development.