Driverless trucks won’t solve the real problem in last-mile logistics, because most of a driver’s time is not spent driving, but walking to drop off packages. For last-mile networks at least, autonomous delivery drones seem to solve a much bigger problem than self-driving trucks would.

But delivery drones suffer from a fundamental problem that will delay their widespread adoption: Their operation lacks the route density necessary to compete with standard delivery trucks. With each delivery, the drone has to return to its homebase at a warehouse many miles away to collect its next package. Compare that laborious round-trip with a FedEx or UPS truck on a “milk-run,” carrying hundreds of parcels, all going in the same direction.

Route density makes today’s last-mile delivery networks extremely efficient.  FedEx and UPS trucks enjoy a marginal cost for dropping off one more parcel as low as $2.00. Drones launching from faraway warehouses won’t be able to compete with this efficiency any time soon.

But do drones and delivery trucks even need to compete? After all, what is a delivery truck but a mobile warehouse? It’s the perfect launching platform for a swarm of delivery drones designed to go the “last-meter” stretch from the street to the customer’s door.

“Swarm” logistics

Releasing a swarm of drones in rapid succession would allow a delivery truck to deliver dozens of parcels in parallel, easily outpacing the output of a single driver plodding through a neighborhood one house at a time. It’s not a stretch to think that a truck releasing a swarm of 25 delivery drones could be up to 25 times more efficient than a driver making those same drops alone.

As an added bonus, this setup would make a residential delivery network so efficient that it could complete all deliveries in the evening hours when people are home, dramatically cutting back on redeliveries. Or better still, fly them into backyards, or into a specially designed chute for accepting package deliveries.

It’s a technology platform that can cut last-mile delivery costs by as much as 96% while improving service.

Perspective on trucking employment

It’s a rough time to be a truck driver. The self-driving truck will have a material impact on American employment—1% of the U.S. workforce currently works as a truck driver.

In addition, if delivery drones get here before fully operational self-driving trucks, they may accelerate the reality of automating driving jobs up to the last mile–an area most assumed would be the last to be affected.

Yet for a 25x efficiency gain in our last-mile logistics network, we’ll have no choice as a society but to consider these technologies.

Where would we be if we had refused the railroad because of its injurious effect on the stagecoach industry?

In the end, the consumer wins

Bold new possibilities emerge when humans are taken out of the logistics equation. We’re barreling headlong toward a world of fully automated delivery, with robots handling merchandise from factory dock to front door.

There are winners and losers in every technological revolution. And one winner here is sure to be the consumer, as delivery prices will drastically be cut. So expect some insanely cool new customer experiences, like Black Friday deals where retailers literally drive into your neighborhood to deliver swarms of hot new products right in your backyard.