Posted on 11/08/2023 10:46:48 AM PST by Red Badger
I think the problem will be them running into things, like other taxis, planes, power lines. Unless they use the present air control system, which would greatly slow down any adoption.
“The Hyperloop. A bus or a streetcar would be a hundred times more cost efficient.”
LA to SF
Bus: 6 hours
HyperLoop: 1 hour
Streetcar: ?
“I think the problem will be them running into things, like other taxis, planes, power lines. Unless they use the present air control system, which would greatly slow down any adoption.”
Same for existing helicopter taxis.
Wasn’t it for lifecycle cost equivalence?
Where did you see the refutation?
“Where did you see the refutation?”
On this site last week.
“Wasn’t it for lifecycle cost equivalence?”
You posted it and you don’t know what it means?
How many pigeon strikes will it take to bring one down?
“How many pigeon strikes will it take to bring one down?”
Bahir Dar, 1988. A flock of speckled pigeons were pulled into the engines of a Boeing 737 passenger airplane as it took off from the runway. One of its engines lost thrust instantly. The other engine failed shortly after during an emergency landing. The 737 crash landed and caught fire, killing 35 of 98 passengers.
https://www.abbynews.com/news/top-5-deadliest-bird-strike-aviation-disasters-in-history-1793113
Many articles here’s just one:
https://www.capitalone.com/cars/learn/managing-your-money-wisely/why-some-hyundai-and-kia-models-are-so-easy-to-steal/2135
The obvious solution is to require a full TCAS and ADB-B suite on every air taxi. ADB-B reports 3d positioning plus full vectors of flight path every one second broadcast to every aircraft in range plus the ground UHF surveillance network. TCAS integrated with ADSB-in is fully cooperative and automated collision avoidance/mitigation.
Both are mature already implemented technology at the commercial level not general aviation. Anyone with an IMC rating is also versed on TCAS its part of the check ride. With digital only flight plan filings which is becoming the FAA nexgen standard every one of these flights would have a flight plan plus ModeC transponder ident even in VMC. Below 500m you are in class E airspace outside the ModeC to ground around class B and above airports. I would expect that no flight plan will ever be granted in a ModeC ground area. It’s the same for helos with the exception of medivac flights.
Your points are entirely valid there is zero reason to go 100% battery electric all the advantages are in the electric drive train. Electric motors are now 10+ up to the pound in power to weight some axial flux are 20HP/Lb this is why you use them as generators are also in this power to weight class. Gas turbines the very best of internal combustion are 6 to 12 horsepower per lb of dry mass. Piston aengines are in the 1 to 2 range with high levels of turbo boost. A gas turbine powering a axial flux high voltage generator feeding multiple rotors is the answer. Add in a small high power but not high energy battery to smooth out the peaks and valleys of demand while running the turbine at its peak efficiency point. You get all the advantages of electric drive train with none of the extra mass of carrying batteries that have 30 times less energy density not power density. Electric drive trains are so light now the Toyota Camry hybrid weights less than the ICE version of it having had its transmission ,differential unit replaced with dual electric motor/gen and a single planetary gear unit. This also doubles the MPG of the vehicle in urban use. EDUs are mature technology.
“why not flying batteries to recharge flying electric taxis?”
That’s a novel thought, but it doesn’t pass the “quick smell test.” It takes ten to fifty times longer to recharge a battery as it does to recharge a liquid fuel tank. The shorter recharging times require huge amount of electricity delivery.
Where would you get such large amounts of electricity in a “battery tanker”? Either it would carry huge amounts of very heavy batteries or it would have an on-board charger. The “battery tanker” itself would probably be powered by JP4, so you would be burning up fossil fuels in the air to deliver a recharge to an in-flight electric airplane. Or the “battery tanker” could have an on-board engine/generator set producing power in the plane (perhaps tapping off one of the main engines on the wing). But what would be the energy source for that engine/generator? JP4, of course.
Sorry, it doesn’t pass the smell test.
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