[XorNot]

Aircraft are more energy efficient then cars[1] at scale. But even a light plane like a Cessna 172 does 13L/100KM[2] depending on flight speed. Certainly more then my Prius, but it can take a much more direct route too.

There's also the simple practical issue: self-driving cars can't navigate a complex crowded environment, whereas self-flying planes navigate a much simpler environment with many more regulatory controls on behavior.

[1] https://www.sustainablebusiness.com/2014/02/surprisingly-air...

[2] https://www.flyouts.com/vliegtuig/cessna-172

[two_handfuls]

I lost confidence at the very beginning of the article:

> In fact, unless you drive a car that gets 33.8 gallons per mile (or carry more than one passenger), new airplanes coming off the assembly line are more fuel-efficient

Cars typically get about 0.03 gallons per mile, so it’s not even close.

[deely3]

> Aircraft are more energy efficient then cars[1] at scale.

Some aircraft and definitely not drons for now.

[krisoft]

What is a drone to you? If you are only thinking about multicopters when you hear that word then yes, those are not efficient and probably never will be.

But the term commonly refers to all unmanned aerial vehicles.

For example a Global Hawk unmanned aircraft can fly 14,000 nautical miles and remain aloft for 42 hours. They are by definition very efficient. That is a drone.

On the other end of the spectrum The Spirit of Butts' Farm crossed the atlantic with 118 US fluid ounces (3.5 L) of fuel. It was flying for ~39 hour and 1,881.6 mi (3,028.1 km). That is about 2045 mile per gallon if I count it right. That is very efficient, and of course since the aircraft was unmanned it is a drone.

[misnome]

> For example a Global Hawk unmanned aircraft can fly 14,000 nautical miles and remain aloft for 42 hours. They are by definition very efficient. That is a drone.

Wow - this is what they are planning to use to deliver packages?

[hef19898]

If so, unit economics will never work, regardless of cargo.

[itishappy]

They use fixed wing aircraft, yes.

[dwighttk]

Do not want what global hawk is delivering

[abtinf]

These are representative of the kinds of drones and aircraft relevant to the context of this post?

[itishappy]

Moreso than the quadcopter you probably have in mind.

[madacol]

zipline's "platform 1" is an airplane, and "platform 2" is a quadcopter shaped like an airplane. https://www.flyzipline.com/technology

So they should have much better efficiency than typical quadcopters

[baq]

Depends on perspective. You could say it's a glider with a quadcopter bolted underneath for VTOL capabilities.

[cma]

If Prius was adapted to run optimally on extremely high octane leaded fuel what could it get?

[bombcar]

High octane does NOT increase total available power, in fact it reduces it.

It enables higher compression so you can get more power per unit of engine weight, but the fuel efficiency per gallon is lower.

And the lead is for the valves.

You can get more efficient planes but you can’t overcome the need to fight gravity at some point.

[cma]

I thought higher octane improved efficiency by avoiding premature combustion, but that may have only been relevant before electronic fuel injection.

[baq]

The Prius doesn’t fly, so let’s not repeat the leaded fuel mistake.