Which makes sense. Most general aviation aircraft engines can run on petrol-pump fuel. Some pilots will land on dirt runways next to consumer gas stations. Petrol is cheaper than avgas. You can find videos of bush plane pilots getting a lot of confused on-lookers taking pictures of the airplane crossing the highway and pulling up to a gas pump. [1][2] Many of the experimental bush planes are using car and snow mobile engines Yamaha, Honda, etc... Car engines while not certified for aircraft are generally more fuel efficient, have longer time between rebuilds and operate better at higher altitudes, support higher RPM and have higher output power. The Zenith uses a Honda Accord car engine. [3]

Instead of a fancy flying car, I personally would just get something like Steve Henry's Highlander [4]. It has the Yamaha EPEX modified snowmobile engine and can take off and land in just a little more space than a helicopter. The wings can be removed by one person in 20 minutes.

[1] - https://youtu.be/PUSKBy3flAs?t=927

[2] - https://youtu.be/kSDJJn9lrkg?t=201

[3] - https://www.experimentalaircraft.info/homebuilt-aircraft/vik...

[4] - https://www.youtube.com/watch?v=zk4teJwQ6FI

I was talking about fuel consumption. Most small aircraft run on normal gasoline, but they usually get the equivalent of 10-15 mpg. The Cessna 172, for instance, gets the equivalent of 13 miles per gallon. This vehicle will be worse than that.

I can see why that would be unclear from what I wrote.

"Its creator, Prof Stefan Klein, said it could fly about 1,000km (600 miles), at a height of 8,200ft (2,500m), and had clocked up 40 hours in the air so far."

That sounds like pretty good mileage? Depending on the size of the tank, 1000km is pretty good range for an automobile.

I guarantee you the tank is yuge compared to what you'd find in a normal car. All airplanes have big tanks.

Well no way will a 12,000 gallon tank fit in the car pictured. That's the size of a semi truck trailer.

So to cruise 1000km it has to get way better than 12kpg or whatever.

Something tells me modern BMW engine will be more efficient than 80 year old design powering that Cessna.

The world records for efficiency are here:

https://www.fai.org/records?f%5B0%5D=field_type_of_record%3A...

The world record for the 1000-1750kg weight class is about 16 miles per gallon. That is burning jet fuel rather than ordinary gasoline. 1000 kg is light for a modern car.

There are no aircraft that can compete with a Prius for transporting small numbers of people. There are few that can compete with a Hummer.

(Note that I'm not sure how the records are calculated. There are a lot of relevant variables, most importantly how fast the plane is flying. And I'm not an aeronautical engineer, just a hobbyist.)

EDIT: More information on that record can be found here: https://lift.erau.edu/for-the-record/

I get a slightly different figure of 17-ish mpg. Still pretty bad.