Terrafugia CEO Responds To "Flying Car" Criticism

waderoush writes "The majority of the comments on last week's Slashdot post It's Not a Flying Car — It's A Drivable Airplane were critical, even dismissive, of Terrafugia's work to build a two-passenger airplane with folding wings that's also certified for highway driving. We boiled down these criticisms to the dozen most commonly expressed points, and today we've published responses from Terrafugia CEO Carl Dietrich. While hybrid airplane-automobiles are an old (some would say laughable) idea, Dietrich argues that current materials and avionics technologies finally make the concept feasible."

Comments

solves the hangar space problem

[wreave]

Great response from Xconomy. The need for an aircraft that can be used for limited driving is real. Some GA (general aviation) airports have very limited and/or very expensive hangar space. In fact, some airports have no available hangar space, in part because companies lease hangar space and use it for business operations rather than aircraft storage. In CA a few years ago, small aircraft were forced out of a hangar so it could be leased to a company that used it for business operations. That's still not right, but at least with the ability to park their airplanes at home and drive to the airport, small aircraft pilots still have options. At the other end, if you're traveling point-to-point, the ability to skip car rental and use your airplane might be an option as well. Obviously, a driveable airplane would be designed for short-distance driving. It's not a car replacement by any stretch of the imagination. (Yes, I am a certificated pilot.)

Re:Just another energy-wasting toy for the rich

[pimpimpim]

I earn my living trying to add my little contribution to advance society through material science, and I, for one, welcome our selfish rich people overlords.

I welcome the rich pensioners that bought Mercedes cars with airbags in the 80's, so that development by Mercedes could be financed and now you get life-saving airbag in even the smallest cars.

I welcome the yuppies that bought the first aluminum bikes, costing probably several thousand dollars back then, but now anyone can have a bike that is light and doesn't rust.

I welcome the showoffs that wanted a mobile phone in the early 90s, so now wireless technology is cheap enough to be used in third world countries, and get people connected.

Should I go on? Advances, especially in materials, are often sustainable because of some marginal hobbies of rich people. They want the lightest and strongest, even when it is actually not needed for their cause (do fishing rods really need to be made out of carbon-fiber?). But the amount of money that they want to invest can keep small innovative companies alive. In the end, we all win.

Re:Just another energy-wasting toy for the rich

[dgatwood]

From http://www.audiouk.com/vintage/telephone.htm

Bell's "speaking telephone" was not universally welcomed. Some people dismissed it as a scientific toy of little value. Others saw it as an invasion of privacy. However, the telephone began to make its way into society, catching the public imagination.

From http://www.evancarmichael.com/Famous-Entrepreneurs/559/Lesson-1-Stick-With-It.html

"Failure is only the opportunity more intelligently to being again," said Ford. "One who fears the future, who fears failure, limits his activities." Even before Ford founded his own motor company, his numerous experiments often led him down the path of failure. Working in a small wooden shack next to his farmhouse, Ford spent years attempting to perfect his automobile design. In one such case, Ford built a steam car that did successfully propel itself, but its kerosene-heated boiler proved too dangerous for it to be driven. "But, I did not give up the idea of a horseless carriage," he said, which at first was considered "merely a freak notion and many wise people explained with particularity why it could never be more than a toy."

Next clueless AC response?

Re:I predicted the demise of Tesla in 3 years

[ScentCone]

The U. S. has collapsed economically ...

I'm sorry, but you're confusing what you want with the actual state of affairs. Why you want it to be that way is a little mysterious, but your ability to confuse it with reality suggests just the sort of disconnect that might drive you to want to see a failed economy, the better to justify your world view.

... and Slashdot covers flying cars.

I'll have to check, but I assume you make the same exact complaint when Slashdot talks about new video boards, hair-splitting differences between Linux distros, the space program, squabbles over pirated movies and music, 4D rubik's cubes, what China does with web filtering, sailing robots, and whether or not Google is obscuring people's faces in Street View? Nah, I won't check, because I'm sure you did.

Re:frost piss

[YrWrstNtmr]

There was that design of two propellers turning in opposite directions with opposed angles, so as to create a blowing air column that takes the "flying saucer" off the ground.

Two words. Gas mileage. Show me any verticle fan craft, carrying 4 adults, that gets anywhere near the gas mileage of any normal car on the road.
Using engine power to hold the craft up is the antithesis of obtaining reasonable mileage.

Now add a gyroscope to that and a second safety thing and a third, so it's impossible to get it upside-down

Hand-waving those hard parts away doesn't make it any easier.
For any type of non-airport ops, we need 6" precision in a heavy crosswind. Why 6"? That's what you do in your car in a parking lot. Not getting upside down is only part of the problem. You have to come down sometime.

Maintenance. A LOT of cars on the road are spectacularly badly maintained. Do you want those same clowns flying overhead, ready to break down?

Thanks for the response

[AeroIllini]

I'd like to take the opportunity to thank Carl for his well thought-out response. It's not every day that busy entrepreneurial CEOs take time out of their schedules to address the unwashed internet masses.

I think this project has a lot of potential. I'm always surprised at the attitude people have that "well, I wouldn't buy it, therefore it's not a good product." News flash, folks: there are market segments you are not a part of. Just because not everyone would buy something doesn't mean no one will. Judging from the number of preorders this has gotten (and knowing many general aviation pilots who would leap at an opportunity to own something like this), I would say it has been very well received.

And he's right about the timing. While carbon fiber technology has existed for a long time now, it is just now gaining traction in general-purpose manufacturing, and the economies of scale are bringing the price down to the point where products can be built with it for roughly the same cost as some other materials. The convergence of affordable composite manufacturing and a new type of sport-plane license have finally made this type of vehicle possible.

The licensing programs for general aviation are much more strict than they are for automobiles. If this vehicle inspires regular car drivers to get their VFR licenses, I suspect the training will also make them better drivers.

However, I don't envy the cost of Terrafugia's product certification program. This vehicle needs to be certified to both FAA and NHTSA standards, which aircraft and automobile companies spend many millions on separately, just for the paperwork alone. Godspeed to the certification team!

Re:Well...

[element-o.p.]

A "drivable airplane" makes sense.
I'm not entirely sure I agree (and yes, I am a pilot). In town, the drag of a car isn't a real big issue; at speeds of less than 30MPH, wind resistance is pretty minimal. At highway speeds of ~60MPH you've quadrupled the drag, and at typical general aviation aircraft speeds of 120MPH, you have 16 times more drag for a given shape and area than at commuter speeds. Consequently, a six foot wide car in town doesn't matter; at flight speeds, the drag of a six foot wide vehicle is pretty significant. That's why the Cessna 152 (a small trainer) is only something like 39 inches wide -- the narrower the fuselage, the less drag. A Cessna 172, a step up from the 152, is only about three inches wider than a 152, and most light single engine airplanes don't get *much* wider than that (I don't recall off-hand how wide a Cessna 206 or 207 -- the biggest single-engine piston airplanes Cessna makes -- are).

What does this have to do with how much sense a drivable airplane makes? Well, the drawings of Terrafugia's design show a vehicle with a cross-section much like a car. It's rather wide, presumably for road stability and passenger comfort. Unfortunately, this makes a poor aircraft design because of the much greater speeds at which even a light sport airplane flies. Terrafugia is claiming some pretty impressive fuel economy numbers for their car, but I'm skeptical. I own a two-place tandem airplane (http://www.gecko-ak.org/N600LW/); it's about as skinny as an airplane can get, meaning its flat-plate area is pretty minimal, and therefore it's drag should be pretty minimal as well. I burn about 4.5 gallons per hour at 60 MPH. That works out to 13 miles per gallon -- better than my Nissan Frontier, but not by much. I sincerely doubt Terrafugia will get 26-27 mpg, as they claim, in a wider vehicle, at twice the speed of my airplane.

Re:Well...

[cecil_turtle]

I'm a pilot as well, if that somehow qualifies one to speak in this discussion. Anyway, you seem hung up specifically on mileage / air resistance. So let me point out a few things:

1) A Cessna 152 (a 30+ year old plane) burns ~6 GPH at 111 knots (Vno), which is about double the fuel mileage of your plane and is quite in line with Terrafugia's numbers. It would seem that your plane just gets poor mileage.

2) Yes, air resistance is exponential, it's relative to the square of the speed - your math is correct. But drag at 30 mph is VERY low, so just saying "16 times that" doesn't mean much. Secondly, to get actual drag you also need to consider drag coefficient and frontal surface area. Frontal surface area is two dimensions - you seem only focused on narrowness. The plane in the article is wide - but it's also a lower profile than "normal" planes. We'd have to have more specific dimensions to know if the overall frontal surface area is more or less than an equivalent plane. Third, as I mentioned above the drag coefficient comes into play. Aerodynamics have come a long way since Cessna's were designed and since your Falcon was designed (20+ years). If you can sufficiently reduce the coefficient, you can increase surface area and end up with the same amount of drag or even less.

Re:I predicted the demise of Tesla in 3 years

[Gavagai80]

You may as well be complaining about the cost of diamonds and moaning that since a hard working Amercian can only afford a few three foot diamonds these days the economy is clearly collapsing.

most people would be happy to trade cars, just they don't have the cash to

Heh, right. Lots of $1000 cars will get 35MPG, your ego just refuses to be seen in them -- you want the trendy status symbol Prius. The same way you refuse to live within 100 miles of where you work, and then complain about gas prices, as though they're the problem.

I'd love to see $8/gallon gas. I spend about $20/month on gas, even on my small income doubling that is a non-issue.

Cars themselves are luxury items, of course, and you're perfectly capable of living in a city and using public transit like most of the world.

Re:I predicted the demise of Tesla in 3 years

[i_b_don]

Wow... talk about negative.

first off, there are plenty of solutions to the "energy crisis". What type of make believe fiticious crap world are we living in where if economics force us to change it's the End Of The World.

1. Solution #1 - switch to an alternate form of energy. There are a ton of options. The last time I checked the sun was still shining and we can still get power from it. Be it solar, wind, or nuclear, there are a ton of options. Why don't we do this? Because the economics don't say we should. Oil is still cheap, but The *second* oil becomes too expensive, there will be a ton of alternate energy sources available to tap. The only reason we don't do it is becuase oil is STILL too cheap.

2. We can also *gasp* change the way we live. Shit, I know i waste plenty of energy. Heating air conditioning... hot water in the mornings, driving to work, pure wastage. How can I get away with wasting energy? Simple, it's cheap. it's less than 5% of my total income so I don't give a crap. I pay roughly 6x that on mortgage. Before the world falls apart, I'm sure we can adjust the way we live at least a tiny bit. But OMG, you may have to sell you SUV and buy a geo metro. Truely the end of the world.

BTW, I'd love to see soemthing backing up that statement about you needing more energy to create a solar panel than all the energy you will ever get out of it. Smells like slanted anti-alternative-energy BS to me, but if you got it from another article or source I'd be interested hearing their twisted logic OR I could even learn something and find out I'm wrong, but i highly doubt it on this issue. Perhaps you're thinking of Ethonal. Either way, source please.

The mortgage crisis.. I guess I don't give a shit. There aren't any losers here. You have gready companies who sold a lot of mortgages when times were good never considering that things may turn south because that might impact their current earnings portfolio. If some of them go belly up its no big shakes to me. I frankly think a few of them SHOULD be put out of business becuase if there was anyone in this mess who was at fault, it was them.

Then you have greedy homeowners who took crazy ass loans or "no paperwork required" loans. Look, buying a house is easily the single biggest investment of your life. If you don't run a few numbers through excel and say "does this make sense" then I don't really feel a lot of pity for you when you can't afford your house. It most likely means you overbought when you got the house (which most people do). But now you've lost your gamble so you have to declare bankruptcy and have to wait 7 years before you buy another house. It's not the end of the world. It sucks, but you took a gamble because housing prices were going up and up and everybody but you was getting rich but you... and now the bubble's burst.

The US is a strong country and we can survive all of these things. The world is not coming to an end. The sky is not falling.

Thank you, but I'll save my pity for a bunch of children who died when their school's clasped after the earthquake in China or other people who actually deserve it.

don