I think this study jumps to many unsubstantiated conclusions in their estimates.

> We assume that operating costs for personnel, loading, and monitoring will be approximately the same per package for truck as for drone delivery.

but at least they included

> There are additional drone costs such as: setting-up and running the drone delivery stations, the investment in research and development, and lobbying the FAA. Other costs include: buildings and land associated with the drone stations, computers and monitoring software systems for drone flights, computer technicians and drone monitors on site, robotics engineers for maintenance and upgrades to drones on site, utility costs of running the building, logistics management team to oversee operations, potential insurance and legal fees associated with drones, and potential air and/or radio frequency rights for drones, etc. There is also the potential for legal costs in some of the following situations: drones are found operating in unauthorized airspace, drones are shot down by civilians, a drone lands in an unauthorized space, etc

There's also mention that the drones can only deliver up to 5lb packages.

Also, I prefer my packages delivered to my door on the porch, not the middle of the yard.

That's a big reason why the hand-wavy stuff is nonsense. The limitless number of exceptions will add a ton of cost, and instead of grunts in trucks you'll need an army of analysts and developers.

I don't have a yard and I share my porch with other people.

Nothing stopping a drone from delivering a package to your porch.

My porch roof and rail and that huge ass rhododendron do. I'd have trouble landing a drone there myself without a 1" box attached

For durable packages there's no technical reason the drone can't sling it between the roof and rail and it's not like delivery drivers don't routinely lob small packages not marked as fragile. Considering how fun to test that one would be I doubt the team responsible is gonna let that feature request ticket sit around collecting Jira dust for long.

Oh theres lots of things stopping a drone delivering a package to my porch, including but not limited to me, I dont want Amazon's drone blowing junk all over the place on my front porch, messing up door decorations, flower pots, whatever it is. Getting caught on a branch, a gust of wind blowing it into a column and causing property damage, my dog grabbing it (my dogs catch birds in the yard, they will certainly hunt this thing). I know the ideal scenario from drone delivery is magical but reality is had, same with autonomous vehicles.

Does this include the externality of drones being way too loud to use frequently in a residential area?

If we're including externalities- how about all of the traffic, noise, and pollution associated with driving delivery vehicles all day long

A drone is way more loud than the various electric delivery vehicles used in Netherlands. Aside from how loud a drone/quad copter is, the noise is also high pitches (more annoying). Traffic is/can also regulated somewhat by limiting the hours that these can operate (at least in NL; though that's usually to businesses). Some of the delivery vehicles have an optimized design, minimizing the space they take (e.g. the ones used for an online supermarket called Picnic).

Aside from electric vehicles some companies (DHL, Coolblue) also use electric bikes.

What a joke of a paper. I could poke a million holes in their assumptions, not to mention their ridiculously simplistic and completely erroneous cost model. There is no way either of them have more than a breath's worth of experience in parcel logistics.