This is just objectively wrong.
Before taking wind into account, a Cessna 172 travels 120kts on a good day and at altitude and appropriately leaned can get down to 8 gallons an hour.
120 nautical miles in 140 miles (less, but benefit of the doubt and all). That's 17.5 miles per gallon. At cruise altitude. Leaned appropriately. You can tack on another few gallons for the climb, and you're going mixture rich on descent so you're back up to 10-11 gph for the last 20-30 miles of your trip. You're lucky to get 10mpg overall for a flight, and that's using gas that costs $5 a gallon.
There are a LOT of benefits to GA flight in order to get around. Fuel efficiency is definitely not one of them.
Also, it may be worth taking into account that airplanes travel in straighter lines.
I fly a Cherokee 140. One of the most common aircraft, as with the Skyhawk. My fuel consumption is 8.4gal/hr at 75% mixture and 5.6gal/hr at 50%. Assuming I'm doing an average ground track of 100mph (for easy math), that's 12-18mpg (not counting that I'm 100% rich at TO and LND).
I wouldn't exactly call it fuel efficient, but it isn't burning like an oil refinery on fire either. I also don't pay $5 for gas ($4.09 today, but it isn't uncommon to see it at $3.50). But you do have to consider speed and time to destination if we're going to compare to cars.
One thing to also consider is that avgas is still leaded. And for anyone interested, here is the POH for the Skyhawk[1] and Cherokee[2]. Note that fuel consumption will be in hours or gal/hr when discussing aircraft. Mpg doesn't make as much sense.
[1] https://www.flyingd.net/documents/N739EF_172N_POH_000.pdf
[2] http://wilgroveairport.net/files/Cherokee%20140%20POH.pdf
Disclaimer: Use the POH provided with your aircraft.
Really all depends where you fly.
If you exclude GA aircraft not designed in the mid-20th century, you exclude 90% of GA aircraft and 99% of certified GA aircraft. We can make that distinction if you want but it ignores reality.
That's been true up until now, but this vehicle doesn't need to do that.
Also, most e-planes have a small motor in the wheel for taxiing.
>I'm talking about overall miles traveled so I'm not sure the straight line thing matters. Yes for the same trip you will travel a shorter distance in a plane.
I think you just answered your own question.
81% of energy produced in NZ is renewable. Complex terrain would make such vehicle a saviour. Plus, in any terrain planes almost always travel less, so savings are intrinsic.
Finally, using "taxi" name here is awful. At the most it's going to be an entertainment device initially (tourism and extremely expensive attractions are insane in NZ), method of access remote places later.
Your conclusion that we must have different value systems only shows where you stopped thinking.
We differ in the timescale on which we consider the betterment of human lives.
And we differ in the subset of human lives we consider the betterment of.
If you remain convinced we have different value systems, then it's not about energy or the betterment of human lives (or straw lives), but about placing a low value on short-sightedness and egotism.
There's a popular perception that all aircraft burn energy like an oil refinery on fire. The reality is that small piston aircraft are approximately as fuel efficient as the vehicles around you on the highway (at least where I live) while getting you there a whole lot faster.
A Cirrus is a good comparison stand in for the KittyHawk aircraft because it has a similar design and construction style (ignoring the dodeca-props), four seats, and is the most common general aviation aircraft not designed in the 1950's. A Cirrus isn't even close to the most energy efficient aircraft - that would be more like 60 mpg, nor is it the most efficient in its class.