Moller Skycar - Myth or Reality?

Factual Questions
1

We started hijacking another thread with a discussion of the Moller skycar ( http://www.moller.com ). This thing has been reasonably big news for a long time, especially in aviation circles. However, I’m of the opinion that the thing is basically snake oil.

Any opinions on this thing?
Dijon Warlock:

Sorry, but the M200X is not a skycar. It was a very different beast, that had 8 engines located around a circular frame, pointing straight down. It has flown in TETHERED flights, never free. And it’s never flown at any kind of speed - the test flights I’ve seen have shown it lifting off, climbing maybe 30 or 40 ft, and then moving left and right a bit before landing.

Still, that’s a fairly impressive trick, which is why I prefer to put Moller in the ‘Dreamer’ category rather than ‘fraud’. He has good engineering skills, and has done some reasonable work in VTOL technologies.

But it’s a HUGE gap from a vehicle with 8 fixed fans pointing straight down, to one with four nacelles that swivel around and provide enough forward thrust to go several hundred miles per hour.

Even so, I’ll be happy to stipulate that Moller’s M400 may one day fly. I can’t find anything specifically wrong with the concept that would prevent that. The problems with it are more operational than technical:

First, his speed and range numbers are completely out of whack, and imply a fuel consumption and drag coefficient that are not possible. Remember, this thing has EIGHT wankel rotary engines. Wankels are reasonably fuel efficient, but his numbers are nuts.

Second, he grossly underestimates the difficulty of getting it certified. Just certifying a simple engine/fan combination could take millions of dollars and years of tests. Trying to build an aircraft comprised of so many untested and uncertified components is a surefire formula for failure. Note that even NASA and the military prefer to do their innovations one piece at a time - innovative airframes like the Osprey or Raptor are almost always tied to off-the-shelf engines and avionics. Otherwise, the complexity of the problem gets out of control.

Third, he grossly underestimates the safety problem. Suck a bird into one of those fans at an altitude below 500 ft or so, and you will die. The front nacelles look like they are perfectly positioned to pick up foreign objects and spit them right into the rear fans.

Third, he is ignoring some serious engineering requirements. For example, the M400 is claimed to be able to fly with one engine shut down, but his fans are not featherable. He’s left that until later. Unfortunately, the problem of designing a light, effective, and reliable fan with feathering blades is monumental, and that alone will kill his entire project, IMO.

Then there’s the issue of training - flying VTOL aircraft is difficult, and very dangerous. Airports and runways are controlled environments - your backyard isn’t. Try to land a skycar on top of your kid’s forgotten bicycle on the lawn, and people could die.

The Harrier has a hideously high accident rate, and it’s maintained impeccably and flown by pilots with the best training in the world. Put a couple of million Harriers in the back yards of everyone, and pandemonium will ensue.

Finally, I have to point out that this guy has been saying that the M400 will be flying in ‘a couple of months’ ever since 1992. How does a respected engineer figure that something will take a couple of months when it actually takes more than 10 years? I think Dr. Moller has a serious problem with reality when it comes to his Skycar.

I’d sure love one if it were real. But don’t hold your breath.

2

There are plenty of questions here. I’ll only answer a couple.

Moller has been around for a long, long time. The flight of the M200X is only one of the final installments of a five-year program of fluff pieces that Popular Science has been floating since at least the early 1980s. I find it somewhat suspicious that the blood-red M400 model appears virtually unchanged from the articles released in 1992.

However, if the ideas presented over the years are to be believed, the basic system is pretty sound. There were originally planned to be eight Wankel-type motors sharing a universal powertrain, so that if any one motor shut down, power would be distributed evenly to all four nacelles. Anyone still bombing around in a Mazda RX-7 knows that the Wankel is a simple, durable, and quite good motor.

Comparatively early in the design phase, safety and idiot-proofing became the focus. Ballistic parachutes capable of deploying from below five hundred feet were considered essential. As the project has progressed, the concept of piloting the vehicle at all seems to have fallen by the wayside. That, no doubt, is part of the delay.

The figures quoted at the Moller website seem to border on the outlandish. Going back to the RX-7, fuel efficiency seems to be a major problem. 15 mpg, from four to eight motors running simultaneously, while remaining quiet and environmentally sane? I think not. Why…?

The greatest reason why I think the Moller is currently non-functional? The Japanese haven’t stolen the idea yet. I’m serious. The second that proof of such a vehicle performing as advertised is released, you’ll see corporations such as Honda and Toyota drop out of F1 racing and similar ventures for a couple of years and have an improved-upon design flying–and racing–before the first Moller gets delivered. Moller has spent a lifetime and perhaps a hundred million dollars without getting solid results (other than a lifetime of really cool work). Mitsubishi could duplicate those results in eighteen months, if they deemed it viable.

3

The whole concept of mass personal aircraft is flawed, whether it’s the Moller Skycar or the Moshier backpack-helicopter thing (which I think is Scam).

Aircraft simply can’t be placed close to each other in the air, even if they are computer guided. Turbulence, wind, lightning, you name it. And the consequences of two Skycars running into each other over a metropolitan area could be devastating. It’ll simply never happen.

Personal aircraft will never be a reliable mode of transportation, and I say that as a pilot who has owned and flown airplanes for 15 years. Hell, even big jets get grounded when the weather goes in dumper. Can you imagine 100,000 commuters being stuck all over a city when the weather goes bad? More frightening, can you imagine how many of those people will try to fly home anyway?

Back to the Moller M400 - There are just so many things about it that are highly questionable, if not downright dishonest. If you work back from the SFC of the Wankel rotary engines they are using, you’ll find that the fuel consumption and range numbers just don’t add up. They’re not even close. And how much lift do the engines have to contribute if the thing isn’t going at full speed? If a lot, then if you have to fly slow you’re still going to be producing a serious amount of power, and range will go through the floor, if it isn’t there already.

Then there is his top speed figure. I just don’t believe that that airframe with all the junk hanging off it and the number of intersections it has can achieve a flat plate area anywhere near small enough to get it going 350+ MPH.

4

I have just one thing to add to the already good points raised above, concerning the transition phase. The problem with designing and building VTOL aircraft isn’t so much the take off or the level flight, as it is the transition between them. Much of the effort in creating a functioning, operational VTOL aircraft centers on the transition phase. For comparison, the first serious VTOL projects were in the mid-50’s and the famous “Flying Bedstead” VTOL test bed was developed in 1954, but the first operational VTOL fixed-wing aircraft was the Harrier. It was 1962 before the Harrier was in operational use. The development of the Osprey has also seen a similar gestation, and is still experiencing teething problems. In fact, the Osprey accident in New Mexico was blamed in part on pilot error during the transition phase.

5

But…but…they said on Art Bell…:eek:

Posted by Sam Stone

Yeah, I know it’s not the “Batmobile” type that they are attributing all the high numbers to, but they do refer to it as a “skycar” on the website, so I was havin’ a bit o’ fun with your statement in the other thread:

Will the Red Monster ever do what they claim? It’s sounding more and more doubtful to me, too. Moller was a guest on Art Bell a few years ago (it was the middle of the night, I was awake; sue me), and he was saying they would be ready for production in a few years…which would be just about now, if memory serves. Accepting $5,000 deposits for those who wish to get the first ones off the assembly line. I wonder how much money he’s raised from that? None from me. I’d rather have a rowbike.

6

Here’s another pie-in-the-sky aircraft that you should avoid investing in: http://www.solotrek.com

7

WOW! Talk about efficiency through technology. The thing looks like a Cuisinart for mass murderers. Just swoop down on people and suck 'em through! Gives duck hunting a whole new angle, though. Instant pate! Feeds hundreds! :smiley:

8

Not all VTOL aircraft are dangerous and diffucult to fly. Just the ones that don’t have rotors. :smiley:

I was working at Edwards AFB when the Moller machines started to get a lot of publicity. One of my co-workers, a non-pilot, was drooling over the concept. I, a pilot with newly-minted wings, explained to him the same thing that Sam Stone mentions here. I told him, “The carnage would be glorious!”

Have you seen some of the cars on the road? Many, many people look at mechanical problems and say, “I’ll get it fixed later. Too many bills this month.” Oh, boy! A couple thousand ill-maintained aircraft! Although aircraft are supposed to be airworthy, there are still a few people who fly their airplanes with things that need to be fixed. Something like this “Jetson-mobile” would have to be meticulously maintained in order to be safe. Then there’s the congestion. People who could afford to buy and fly one would probably live in cities, and they’d all be using the same routes. How many “fender benders” did you hear about on the radio today? Training? They’d still have to be certified pilots. (The FARs include a section on “powered lift” aircraft.) Sam Stone mentions bad weather. Supposedly, the weather would not be a factor because the computer would do the flying and make corrections much faster than a human could. Call me old-fashioned, but I don’t want to fly in conditions that I could not fly out of if a computer failed. (Note: I am not instrument rated.) Besides, what if it used a Windows operating system? :wink: :eek:

Flying is a game of balances. We all know about lift, gravity, drag and thrust; but there are other balances: Payload, range, speed, maneuverability, money. I’m sure a Skycar could be built that performs as promised; but at what cost? Turbine engines ain’t cheap! Speed = money. A Cessna 152 will do, what? About 110 kts? You can buy a used one for $20,000 or less. The new Piper (I don’t recall the name) is almost twice as fast… and it costs over $1 million. You want performance? You have to pay for it!

So here’s my take: The technical problems are many and large. If they can be solved, the machine will be too expensive for 100,000 people to buy them. If the Skycar is successful (it flies, performs as advertised, and people buy them) then there’s the problem of thousands of them sharing the same airspace, with each other and with other fixed-and rotary-wing aircraft in the system. People who own them would have to be extremely fastidious about maintenance and not “let things go” as often happens with their cars. People on the ground will be killed; and since the idea of the Skycar os to fly into congested areas and the glide ratio will be poor, the potential is there for many people on the ground to be killed. As I said a decade and a half ago, “The carnage will be glorious!”

It’s a nice dream, but that’s all it is.

9
      • As I recall, Moller had a swoopy Jetsons-type vehicle planned, but built a UFO-round shaped one for proof of - , well, proof of something. The round one is the one I have seen photos of actually flying.
  • Rotary engines probably can’t deliver the efficiency needed for his MPG numbers. - MC