For package delivery, the “last mile” has always been the most complicated and expensive to complete. Now with companies large and small pursuing drone deliveries, the last few feet of the parcel delivery will become the sticking point.

A recent decision by the Federal Aviation Administration brings the possibility closer to reality, but don’t expect a fleet of package-bearing drones to ever darken the sky.

The delivery idea is attractive as drones become more common.

But for package delivery, the hurdles are both technical and strategic. The safe hand-off from a flying machine the size of a push lawnmower with rotors whirling at high speed is an obvious one. Another is weather. And drone delivery of a single package defies any economy of scale.

Still, package delivery by drone has received much hype, but this use always stretched the technology and requires new regulations. To unleash the delivery potential, the FAA would have to allow drones to fly beyond the line of sight of an operator with the faith that the technology would keep them from crashing into something or someone.

The FAA took a step toward this reality last week when it granted so-called type certification to a delivery drone built by Matternet, a startup in Mountain View, Calif. This certification marks the first nonmilitary drone that the FAA has deemed safe to fly over people and will be able to fly everywhere regulations allow the aircraft. This process took four years, so the technology is being rolled out methodically.

The FAA currently gives exemptions to companies for long-distance flights on specific routes without an eyes-on monitor. Wing Aviation LLC, Amazon.com Inc. and a United Parcel Service Inc. unit have delivered packages by drone under this certification. The agency plans to replace its current practice with general rules for flying beyond visual line of sight, and when that happens, drones like those made by Matternet will be unleashed. This will allow long-distance flights for inspecting pipelines or railroad tracks or delivering packages.

Matternet is one of the more advanced drone delivery companies and underscores how the technology can work in a niche setting. It has been shuttling health care items for years between hospitals that are 3 miles apart in Zurich. The startup is setting up a citywide medical drone network in Abu Dhabi. In the U.S., the company has worked with UPS to make deliveries of laboratory-type items on hospital campuses in the U.S. and parcels from a CVS pharmacy to a Florida retirement community.

Health care is a unique market because there’s urgency for some deliveries, which command a price premium for speed. Deliveries of lab results can fetch $20 to $40 for each item, even over short distances. These deliveries usually follow specific routes, say between laboratories at two separate hospitals. For these deliveries, Matternet has designed a large pod that the drone can land on without getting near people. The packages are left and picked up at the pods, and the drone can even autonomously swap out a spent battery for a charged one.

This won’t be the case for e-commerce. People have become accustomed to finding their packages close to their doorsteps or building entrances. The FAA isn’t keen on these vehicles taking off and landing by themselves near people.

Companies pursuing drone deliveries, including Amazon and Walmart Inc., are trying different solutions to drop packages at homes.

The biggest hurdle is that drones will be making point-to-point deliveries, which is the quickest but most inefficient way to take packages to homes or businesses. The drone will travel out and back from a warehouse to deliver one item. This may create a premium market for emergency deliveries, but it would take a small army of drones to service the 150 to 200 packages that just one truck normally takes on a route.

While drone technology has improved and the aircraft can detect and avoid objects in the air, they can’t fly in heavy wind or rain nor icy conditions. UPS doesn’t stop delivering when the weather is bad.

Then there is the reaction from consumers. Do they want drones buzzing around their neighborhoods?

There is a place for delivery by drone. Despite the hype in the e-commerce market, it’s unlikely the sky will be studded with packages coming in for a landing on doorsteps.

Distributed by Tribune Content Agency, LLC.