New Mars Forums

kbd512

Administrator

Registered: 2015-01-02

Posts: 7,852

Re: Flying Car

tahanson43206,

1.  I'll bet it was tested- by a very experienced test pilot, probably an ATP-certified guy or gal with thousands of light hours and a CFI rating.  For that particular man or woman, I'll bet it wasn't a problem at all.  Doctors think competence in medicine transfers over to flying high-performance complex aircraft like a Beechcraft Bonanza once per month or per year, and they call those otherwise excellent aircraft "forked-tail doctor killers" for that reason.  Whenever you're testing a new aircraft, everyone knows it's common practice to put an inexperienced pilot behind the controls- NOT!

2. The short answer is yes, but if you need stability control in your personal aircraft, then how would that not be construed as a sign that your design requires more training and experience to use without potentially painting yourself into a corner with your lack of skill and experience about what you're doing?  I'm not claiming their design is "wrong" or "bad" if their design goal was to create an aircraft that could also drive on the highway, but at that point is this still something you're going to allow a novice pilot to use?  Probably not.

We're building a flying car that can hover and go 300mph.  It's "so easy to use", because it has augmented stability control.  Now we're going to hand over this complex high-performance machine over to a pilot with lots of money but maybe 100 hours to his or her name.  What could possibly go wrong?

Read Kathryn's Report if you want an answer to that question.  It's pretty graphic, but should also sober up people with more enthusiasm than personal knowledge and experience.  Things can and do go wrong a lot faster than many of the people at the controls can handle them.  Note the number of highly experienced pilots who were seriously injured or killed in their high performance personal flying machines.

3. Yes, pilots opt for different runways or go-arounds on missed approaches if crosswinds or turbulence are causing problems.  Experienced pilots, especially ATP-rated ones, know that firewalling the throttle and going around is the correct way to clean up after a bad approach, but do less experienced ones know this?

Throttle in, gear up, don't touch the flap lever, lower the nose, fly the speed (the one that keeps you in the air, if that part needs to be said).

4. No.  You need actual experience landing in crosswinds.  Simulators are not a replacement for the immersive experience of flying.  That's why you only get a handful of "flight hours" added to your logbook by doing training in a simulator.  The rest have to be behind the controls of a real aircraft.  The sorts of simulators found in most flight schools are not the same quality as commercial aircraft simulators that move on hydraulics, make noise, and cost millions of dollars- more expensive than all of the flight school's training aircraft sitting on the tarmac.

These are probably not the answers you want, but they still represent the unpopular truth, nonetheless.  A "flying car" is a DOA proposition for me.  It's either a poor car or a poor aircraft, or it's mediocre at both driving and flying.  Calliban already told you why.  I'm merely providing more specifics as to the underlying reasons, and yes, it relates back to meeting opposing design requirements.  I also think battery-powered cars are still a much better proposition than flying cars, if that tells you anything, and you know quite well what I think of those.

Mars_B4_Moon

Member

Registered: 2006-03-23

Posts: 9,776

Re: Flying Car

Not a car and very expensive

Xturismo: Japan Launches The World's First Flying Bike
https://yodoozy.com/worlds-first-flying-bike-is-here/

tahanson43206

Moderator

Registered: 2018-04-27

Posts: 19,365

Re: Flying Car

https://www.msn.com/en-us/travel/news/t … 77b37&ei=7

The link above is to an announcement of an all-electric flying car winning FAA approval for testing.

Shipments are planned for 2025. Air range is 115 miles and road range is (about) 200 miles.

These might appeal to Wall Street bankers wanting to commute to homes in the suburbs.

(th)

kbd512

Administrator

Registered: 2015-01-02

Posts: 7,852

Re: Flying Car

A Wall Street banker will take the elevator to the rooftop of his / her place of work, hop into a real helicopter crewed by a pair of professional helicopter pilots, and land on their front lawn.  For any motoring that they care to do, they already have a Rolls Royce and chauffeur.

How many people who have $300,000 of disposable income, also want a functionally useless helicopter-car gadget that will never pass a NHTSA crash test and glides like a brick if it ever loses power?

Is this Jim Dukhovny character Stockton Rush's long lost brother from another mother?

If electric VTOL is such a great idea, then why not simply build an electric helicopter and be done with the entire electric gimmick?

Why must there be an endless cycle of pointless novelty to something that could otherwise be a modestly functional flying machine?

They're solutions in search of a problem to solve.

tahanson43206

Moderator

Registered: 2018-04-27

Posts: 19,365

Re: Flying Car

The video at the link below shows a type of rotor lift system that is new to me ... perhaps other members and readers might find it interesting...

https://www.msn.com/en-us/autos/news/ne … 9efd&ei=32

The device definitely appears to be able to lift itself, but whether it can do anything beyond that is a question.

(th)

kbd512

Administrator

Registered: 2015-01-02

Posts: 7,852

Re: Flying Car

tahanson43206,

This looks like a Voith-Schneider propeller, but enclosed on both ends instead of just one.  IIRC, these devices require continuous control over unsteady state aerodynamic or hydrodynamic forces.  I don't know enough about them to know if they provide significant advantages over more traditional types of propulsion, apart from the ability to rapidly change direction, but I suspect there are some fairly substantial tradeoffs at play.  As near as I can tell, you're in a helicopter with no auto-rotation capability.  It the machine loses power, you're going down at a non-survivable vertical velocity.  This may not matter for something like a combat drone, but a serious issue for a helicopter carrying humans.  I don't think this is fundamentally new technology, though.  IIRC, the cyclorotor was a Russian design from around the dawn of powered flight.

It's intriguing, but mastering this sort of propulsion system is non-trivial.  It could be used on a more conventional aircraft to provide both thrust and blown wings or flaps for additional lift.  I need to read some more to figure out where the limits are.  I suspect it's limited by the reliability of the control system, the longevity of bearing surfaces, and the strength of the blade materials.

tahanson43206

Moderator

Registered: 2018-04-27

Posts: 19,365

Re: Flying Car

Following up on the tip by kbd512 in post #31, I asked Google for help finding a bit more about the type of fan used in the experimental car at the link in post #30...

Google seems to ** think ** this might be an "axial" fan ...

Axial fans are a line of industrial fans commonly used today. The propeller structure is mounted parallel to the direction of the fan shaft, creating a suction and blowing direction parallel to the fan axis. In the HVAC system, industrial axial fans are used for cooling, ventilation, and air conditioning.Nov 8, 2022

What I learned is that this is ** not ** a "drum" fan ... that description is given to ducted traditional propeller fans.

(th)

Mars_B4_Moon

Member

Registered: 2006-03-23

Posts: 9,776

Re: Flying Car

Are Flying Cars Finally Here?
https://www.newyorker.com/magazine/2024 … nally-here

China's flying cars ready for liftoff with EV technology
https://asia.nikkei.com/cms/Business/Tr … technology
XPeng AeroHT, a subsidiary of the electric vehicle startup, aims to sell a dual-mode electric vertical take-off and landing

Flying cars: The future of personal mobility
https://www.bbc.com/reel/video/p0hq2hhy … l-mobility

Ingenuity's Flight Map
https://www.youtube.com/watch?v=U7DFnNimSfw

There is still debate how much a flying vehicle can lift on Mars, some say a school bag, maybe something the size of a cat, a bag of grain and seeds, some bottles of medicine or a few guinea pig hamsters.

There was also a time when some very educated people with experience in physics and engineering said nothing would ever fly on Mars

tahanson43206

Moderator

Registered: 2018-04-27

Posts: 19,365

Re: Flying Car

For Mars_B4_Moon re #33

The sentiment you have reported in the quote below is well documented to have happened on Earth.

I suspect you might have projected the experience documented on Earth on to Mars.

I would be quite surprised if you are able to find a quote from anyone with a degree in engineering or physics who would have made such as prediction for Mars. The science of flight has advanced significantly since 1903. 

As a challenge, please see if you can find ** any ** such prediction by a person with a reputation at stake.

There was also a time when some very educated people with experience in physics and engineering said nothing would ever fly on Mars

What I think you ** may ** find are predictions (by knowledgeable people) that flight on Mars will be very difficult.

A prediction that something will be difficult is ** not ** the same as a prediction that it is impossible.

Per Google...

New York Times about difficulty of air flight

1956 Astronomer Royal of Britain about space flight

(th)

Mars_B4_Moon

Member

Registered: 2006-03-23

Posts: 9,776

Re: Flying Car

As a challenge, please see if you can find ** any ** such prediction by a person with a reputation at stake.

(th)

Lots of Anonymous chatter out there, you find people on quora or medium or stackexchange or twitter or slashdot or facebooks or substack for example, those who have made their private info public I will not ruin a reputation by mocking them, they can ruin their own reputations making bad prediction.

and here also Twenty years back 2004,

this guy an old forum member was quiet knowledgeable at times, he was a well educated man by the way he wrote and from his style of writing had some engineer experience. I never got much public info on him but he claimed to have worked in some indirect way with industry or even 'Nuclear Energy' at times he seemed obsessed with Nuclear gas-core-reactor rockets and thought they would be the solution to Mars colonization, he registered in 2003 and stopped posting in 2008.

2004 quote

A neat idea, but i'm going to have to weigh in against, I don't see the idea as having enough merit. Short-term (<1 martian day) scouting with an airplane that is too light to hold much useful equipment and too light to carry a good communications system to transmit it isn't worth it.

There might be a reason some people who do have experience but talk online quietly with no personal info out there, have not put too much reputation in public and communicate by anonymous user name or anonymous twitter avatars, we had less advances in material sciences and technology has moved on
2004 was also a time when people were still plugged out of 'The Matrix' lets say and somewhat off the grid, before all the facebooks, video gamers and online educators and youtubes and every other social media
maybe science has moved forward and some of the older experts did not see where it would go

with the success of Ingenuity in 2021, nicknamed Ginny we can see a type of aircraft can hold 'useful equipment' and can indeed hold communication systems to transmit

Last edited by Mars_B4_Moon (2024-05-18 05:50:26)

Mars_B4_Moon

Member

Registered: 2006-03-23

Posts: 9,776

Re: Flying Car

staying on the flying car topic

'Volocopter becomes world’s first eVTOL Approved Training Organisation'
https://www.jpl.nasa.gov/news/nasas-ing … ye-for-now

and back to the Mars Helicopter

'NASA’s Ingenuity Mars Helicopter Team Says Goodbye … for Now'

https://www.jpl.nasa.gov/news/nasas-ing … ye-for-now

Mars_B4_Moon

Member

Registered: 2006-03-23

Posts: 9,776

Re: Flying Car

'Flying car' makes Tokyo debut at international tech event

https://japantoday.com/category/tech/fl … tech-event

kbd512

Administrator

Registered: 2015-01-02

Posts: 7,852

Re: Flying Car

This thing has 18 motors and propellers- all that ridiculous nonsense to avoid building an electric helicopter.  It boggles my mind how people can make something which should be simpler than a gas turbine helicopter, inordinately more expensive and more complex.  It's neither a good car, nor a good helicopter.  If it ever loses power, if falls out of the sky like a brick, because it has zero auto-rotation capability.  Sometimes I wonder how much the people peddling this nonsense get paid.

kbd512

Administrator

Registered: 2015-01-02

Posts: 7,852

Re: Flying Car

If all the time and money squandered designing these silly eVTOL "not helicopter" helicopters was instead used to build an actual battery operated helicopter capable of transporting humans, we would quickly reach the conclusion that they were not very practical on account of the battery limiting the range- something about 0.25kWh/kg vs 12kWh/kg for kerosene, not substantially less noisy since the rotor blades make most of the noise, and not substantially less dangerous to fly than any other rotary wing aircraft, on account of the simple fact that maintaining the rotor blades and gearboxes, combined with their general inefficiency, are what make helicopters more expensive to fly than regular fixed wing aircraft, regardless of power source.

Instead, we "dazzle them we BS", by using 18 scooter motors and the cheapest Chinese LiPo batteries money can buy.  Oddly enough, not a single one of these machines is FAA type certificated, because they are more expensive than regular helicopters for what you get, they don't perform like real helicopters or real cars, and present battery technology is what prevents them from ever doing so.

Someone needs to design a 6kWh/kg battery first, assuming the battery is 50% more efficient than a kerosene burning gas turbine engine, and then we can pursue eVTOL helicopters or "not helicopter" helicopters.  Until then, this stuff is a waste of time and money, the market for such battery operated devices is exceptionally limited given that most of our EV crazies aren't kamikazes, and none of these battery operated flying devices are any lighter or cheaper than actual helicopters for the range provided, which is what makes them more expensive than combustion powered flying vehicles.

Whenever the spell finally breaks, a lot of investors and "early adopters" who are not outright killed by these dumb toys, are going to need to look for new ways to blow mad money on things that fundamentally don't work and probably never will.

SpaceNut

Administrator

From: New Hampshire

Registered: 2004-07-22

Posts: 29,431

Re: Flying Car

Tech startup announces flying motorcycle prototype with impressive airborne features — here's how it works

tahanson43206

Moderator

Registered: 2018-04-27

Posts: 19,365

Re: Flying Car

For SpaceNut re #40

Thanks for the link to this impressive achievement!

What I like about this is that a group of funders were willing to invest in the development of this advanced technology, despite the naysayers and Debbie Downers who pop up from time to time. 

The vehicle itself can only fly for 25 minutes or so, and in fine weather, but at 141 miles per hour (or even just 100 miles per hour) it might be able to carry a bold individual from a suburban home to a downtown office.

I hope the company is able to find buyers for this product.

The prototype is unique in its development to generate 430 horsepower with "hummingbird-like" agility, as New Atlas detailed. Built as fully electric with four fan units that move independently, there is less of a strain on the batteries that power the aircraft to provide a longer range of flight.

Since the prototype was announced, the company has noted areas for improvement. While the Airwolf is built with speed and agility in mind, it is limited to 25 minutes of flight time. To fly the prototype in the United States, drivers are required to attend 20 hours of flight training to receive a sports pilot license. Customers would have to dig deeply into their wallets as well to cover the $320,000 purchase cost, according to Captain Electro. 

According to a publication by ScienceDirect, the benefits of the technology behind evTOLs include a reduction in traffic congestion from traditional vehicles, zero direct pollution as they use electric propulsion systems, and a decrease in noise levels for urban areas compared to standard vehicles. This leads to safer travel and cleaner air for communities.

This would seem to be a strong candidate for microwave power service from the ground, along a line of travel.

(th)