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Terrafugia's flying car model has been approved for tests in US airspace

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Re: Terrafugia's flying car model has been approved for tests in US airspace

#11

Post by jobu »

geff82 wrote: post #7

"Flying Car" seems so cool, but really think about it. Would you drive your car-airplane around on the ground all the time? An airplane already costs lots of money to maintain when it is only flying and sitting at the airport. Now you also have to pay even more for it for the wear of driving on the streets. I mean, this is really only an option to drive from your home to the airport from time to time (not for every f…

Their promotional video shows this vehicle as a VTOL aircraft, so theoretically you could drive to a parking lot and go : https://www.youtube.com/watch?time_continue=188&v=wHJTZ7k0BX...

However, even if they do get the VTOL working successfully (many others have failed) there will likely be some regulatory hurdles for flying out of a neighborhood. That isn't unheard of though. There are suburban communities built around small airports with direct access to the runways (similar to golf course communities).

Re: Terrafugia's flying car model has been approved for tests in US airspace

#12

Post by Someone »

lukev wrote: post #6

I'm not an aeronautical engineer, but the fuselage/wing size ratio on that is way bigger than anything I've seen that actually flies. Is something that looks like that even a little bit possible?

Given enough power, a brick can 'fly'.

This more likely is a flying body (https://en.m.wikipedia.org/wiki/Lifting_body) or a blended wing body (https://en.m.wikipedia.org/wiki/Blended_wing_body), as 'give it an enormous engine' hurts economical feasibility.

But yes, it looks as if those wings are there only to have something to hang the engines from.

Re: Terrafugia's flying car model has been approved for tests in US airspace

#13

Post by jacquesm »

balabaster wrote: post #9
Xophmeister wrote: post #8

Why would anyone realistically -- i.e., outside the realm of pure fantasy -- want a flying car? People can barely handle one-and-a-bit dimensions at 70mph (i.e., a road with discrete lanes), how well do you think the general population would cope with this? Maybe autonomous flying vehicles would be more practical, but that still leaves the other two main problems wide open: 1. The energy required to keep the vehicle…

> People can barely handle one-and-a-bit dimensions at 70mph +1 just for this statement alone. So far, statistics say that flying is safer by orders of magnitude than driving your car... that statistic will likely plummet to many orders of magnitude in the opposite direction if flying cars become a thing. If we do end up with flying cars being the norm, I would hope they will be autonomous and not have people manuall…

Correction: statistics say that commercial air travel is safer by orders of magnitude than driving your car.

General aviation is already a lot worse than that today, and even pilot certification does not preclude accidents in general aviation. It is the whole process around safety put into practice at commercial airlines and numerous design details present in commercial aircraft that make flying with a commercial carrier as safe as it is.

Re: Terrafugia's flying car model has been approved for tests in US airspace

#14

Post by mtgx »

Xophmeister wrote: post #8

Why would anyone realistically -- i.e., outside the realm of pure fantasy -- want a flying car? People can barely handle one-and-a-bit dimensions at 70mph (i.e., a road with discrete lanes), how well do you think the general population would cope with this? Maybe autonomous flying vehicles would be more practical, but that still leaves the other two main problems wide open: 1. The energy required to keep the vehicle…

Which is why even before the whole "self-driving" car madness started, I was thinking flying cars will never work unless they are fully automated.

A flying car should only be required the destination as input.

Re: Terrafugia's flying car model has been approved for tests in US airspace

#15

Post by jobu »

lukev wrote: post #6

I'm not an aeronautical engineer, but the fuselage/wing size ratio on that is way bigger than anything I've seen that actually flies. Is something that looks like that even a little bit possible?

Not the most successful comparison, but it looks proportionally similar to the V-22 Osprey (also a VTOL aircraft).

Re: Terrafugia's flying car model has been approved for tests in US airspace

#16

Post by toyg »

Xophmeister wrote: post #8

Why would anyone realistically -- i.e., outside the realm of pure fantasy -- want a flying car? People can barely handle one-and-a-bit dimensions at 70mph (i.e., a road with discrete lanes), how well do you think the general population would cope with this? Maybe autonomous flying vehicles would be more practical, but that still leaves the other two main problems wide open: 1. The energy required to keep the vehicle…

There is a chance to do with flying cars what we couldn't do with regular cars: force them to be fully autonomous by default. No safe automation, no permit. This would likely mean forcing them to use some sort of target "airparks" for takeoff and landing, at least initially, but it would drastically reduce the chance of accidents.

Re: Terrafugia's flying car model has been approved for tests in US airspace

#17

Post by fit2rule »

Xophmeister wrote: post #8

Why would anyone realistically -- i.e., outside the realm of pure fantasy -- want a flying car? People can barely handle one-and-a-bit dimensions at 70mph (i.e., a road with discrete lanes), how well do you think the general population would cope with this? Maybe autonomous flying vehicles would be more practical, but that still leaves the other two main problems wide open: 1. The energy required to keep the vehicle…

I once drove a very nice car from Essen, Germany, to Cambridge, UK. On the way I had to take a ferry from the Netherlands .. I would have been much happier not having had to take that ferry. I think a flying-car would be the perfect application in that scenario ..

Re: Terrafugia's flying car model has been approved for tests in US airspace

#19

Post by jacquesm »

jobu wrote: post #15
lukev wrote: post #6

I'm not an aeronautical engineer, but the fuselage/wing size ratio on that is way bigger than anything I've seen that actually flies. Is something that looks like that even a little bit possible?

Not the most successful comparison, but it looks proportionally similar to the V-22 Osprey (also a VTOL aircraft).

Not really, the Osprey has much more horizontal wing surface relative to its size and it has a tail surface and double stabilizer as well. That's a completely different geometry much closer to a conventional aircraft than the subject of this thread. This new vehicle also has a ducted fan for more forward thrust (I suspect this is because mounting larger tilt rotors was impossible given the constraints on height of the vehicle).

It'll be a close race between this one and the Moller sky car which one will hit the dealerships first.

/sarcasm.

Re: Terrafugia's flying car model has been approved for tests in US airspace

#20

Post by billbail »

They claim "1 MW" of power is supplied to the motors with batteries and a 300bhp engine but since 1 bhp =(roughly) 0.75 KW the batteries would need to supply 775KW the power and the combustion engine would not be able to keep the batteries charged sufficiently.

I'm not an expert on car power systems but this doesn't appear to be feasible.

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