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Boeing Working on Fuel Cell Aircraft

samzenpus posted more than 7 years ago | from the 12,000-AA-batteries-not-included dept.

Power 163

"Boeing is working with development partners on a fuel cell-based small aircraft. It seems like a logical use of the technology. Now if they can come up with a quiet, personal-sized VTOL craft a la Paul Moller's Skycar (which is anything but quiet), we'll really have something." From the article "A Boeing research director was quoted as saying, "While Boeing does not envision that fuel cells will provide primary power for future commercial passenger airplanes, demonstrations like this help pave the way for potentially using this technology in small manned and unmanned air vehicles."

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Better hurry up... (3, Funny)

kmac06 (608921) | more than 7 years ago | (#18523101)

I want my flying car by 2015 [wikipedia.org] .

Re:Better hurry up... (2, Funny)

$RANDOMLUSER (804576) | more than 7 years ago | (#18523163)

I realized that Popular Science had been lying to me about flying cars when the diesel powered typewriter they predicted never materialized.

Re:Better hurry up... (1)

kmac06 (608921) | more than 7 years ago | (#18523331)

Hook up a diesel-powered UPS to a computer!

Re:Better hurry up... (1)

El Torico (732160) | more than 7 years ago | (#18523293)

I have horrible visions of the skies over Naples, Italy if that happens.

Re:Better hurry up... (1)

peragrin (659227) | more than 7 years ago | (#18523499)

I have horrible visions of a 2000 car flying pile up.

Re:Better hurry up... (0)

Anonymous Coward | more than 7 years ago | (#18523687)

Air routes have a way of being "self-cleaning" unlike a freeway. You collide with another plane, and you won't be in the way of traffic for much longer. The most damage you could have is maybe 2-4 flying vehicles, and some unlucky building on the ground. That said, the psychological impact on the public of a collision between two flying vehicles would far exceed that of a 2000 car pileup.

Re:Better hurry up... (1)

Solra Bizna (716281) | more than 7 years ago | (#18526053)

the psychological impact on the public of a collision between two flying vehicles would far exceed that of a 2000 car pileup.

Not to mention the physical impact. (How likely am I to survive crashing into another car and then falling 60 or more meters to the ground?)

-:sigma.SB

Re:Better hurry up... (4, Funny)

GFree (853379) | more than 7 years ago | (#18523515)

I'm sure in 2015 plutonium is available at every corner drugstore, but in 2007 it's a little hard to come by.

Skycar (5, Funny)

Anonymous Coward | more than 7 years ago | (#18523109)

The Skycar is vaporware. It has been for the last 30 years. Please don't use the Skycar as a benchmark for anything but hype and failure.

Re:Skycar (0)

Anonymous Coward | more than 7 years ago | (#18523323)

Amen! I remember reading about the Skycar in "Popular Mechanics" in the library way back in middle school... WAAAAY back. Let's not pretend any longer that we'll all one day be flying about in our own personal jets. Most people have enough trouble controlling a vehicle with two degrees of freedom. There's a very good reason why getting a pilot's license is much harder and more costly than getting a driver's license.

Re:Skycar (1, Interesting)

kmac06 (608921) | more than 7 years ago | (#18523367)

Of course not everyone should be allowed to pilot/drive a flying car. But that doesn't mean there will never be a cheap (~$30,000) flying car/plane that will require a pilot's license to operate.

Re:Skycar (0)

Anonymous Coward | more than 7 years ago | (#18523513)

You can already buy a Cessna C172 for $30,000. They might be older but they still fly. What is really needed is airplanes which require lower maintenance fees and I don't think you'll get that by stuffing ever more expensive tech into them.

Re:Skycar (1)

YrWrstNtmr (564987) | more than 7 years ago | (#18523595)

What is really needed is airplanes which require lower maintenance fees

A&P certified mechanics are expensive.

Re:Skycar (2, Insightful)

QuantumG (50515) | more than 7 years ago | (#18523601)

No, what's needed is vertical take off and landing vehicles for that price which don't make insane amounts of noise or vent extremely hot gases in a way that is dangerous to third parties. Without that, you can't replace a car with a plane, assuming that's what you want.. I know it's what I want.

Re:Skycar (2, Insightful)

YrWrstNtmr (564987) | more than 7 years ago | (#18523647)

No, what's needed is vertical take off and landing vehicles for that price which don't make insane amounts of noise or vent extremely hot gases in a way that is dangerous to third parties.

And to do that we just need to suspend the laws of physics. Unless you know of another way of lifting 2,000 lbs straight up in the air.

giant rubber bands (3, Interesting)

Quadraginta (902985) | more than 7 years ago | (#18523759)

...or some kind of powered trampoline.

This isn't totally humorous, incidentally. Think of aircraft carriers. You can achieve very short take-off distances without putting the giant (noisy) vertical-flight machinery on your aircraft -- because you can just leave it on the ground behind you. But you must then accept the fact that you can only launch in certain places.

Still, I'd bet there's a market for a cheap skycar that can only launch at certain public facilities but can land nearly anywhere.

Re:giant rubber bands (1)

YrWrstNtmr (564987) | more than 7 years ago | (#18523841)

But you must then accept the fact that you can only launch in certain places.

If you have the launch facility, you also have the landing facility. So we're back to the standard (cheap) Cessna.
Landing 'anywhere' = vertical landing. Loud, dangerous (crosswinds) and expensive on fuel.
Without some uber propulsion type (not fans pushing air), I don't see it happening any time soon.

Re:giant rubber bands (3, Funny)

Calinous (985536) | more than 7 years ago | (#18526049)

Ships and submarines have launching facilities for cruise missiles. They miss landing facilities for them, however.

Re:Skycar (1, Funny)

QuantumG (50515) | more than 7 years ago | (#18524213)

Unless you know of another way of lifting 2,000 lbs straight up in the air.
Step 1: ask the 3 american passengers to hop out.

Re:Skycar (1)

nothing now (1062628) | more than 7 years ago | (#18524579)

heyy... we're not all fat!
  I'll have you know I only wheigh 250 lbs or 113.4 kg and I'm 6ft 1 inch or 1.85 meters abouts.
so sod off! , only lazy suburbanites and welfare families are that fat.

Re:Skycar (1)

QuantumG (50515) | more than 7 years ago | (#18524691)

Unnecessarily tall. :)

Re:Skycar (0)

Anonymous Coward | more than 7 years ago | (#18525117)

OK, I know this is probably a joke (sod off? Who the fuck in the US says that?), but 6'1 250lbs is a fat fucking fuck. I'm 6'4, if I weighed 250 I would cry every day of the week. It's a BMI of 33, which is pretty firmly in the "obese" category.

Re:Skycar (1)

geobeck (924637) | more than 7 years ago | (#18524765)

Step 1: ask the 3 american passengers to hop out.

Conveniently enough, that will also take care of much of the noise and venting of hot gases.

:

Re:Skycar (1)

TooMuchToDo (882796) | more than 7 years ago | (#18525455)

How about dropping the vertical takeoff and landing requirement, and simply using general aviation airports? According to Wikipedia, there are 5,288 GA airports in the US.

Re:Skycar (1)

micknz (813240) | more than 7 years ago | (#18526043)

And to do that we just need to suspend the laws of physics. Unless you know of another way of lifting 2,000 lbs straight up in the air. Sylar can do it, why can't we?

Re:Skycar (1)

mpe (36238) | more than 7 years ago | (#18526255)

No, what's needed is vertical take off and landing vehicles for that price which don't make insane amounts of noise or vent extremely hot gases in a way that is dangerous to third parties.

The only way you get vehicle capable to taking of vertically is by having a thrust to weight ratio of greater than 1. Ideally thrust significently greater than the weight of the vehicle (including pilot, passengers and luggage). The only easy way to do this is by moving a large amount of air.

Cheap aircraft (1)

wasted (94866) | more than 7 years ago | (#18524437)

You can get everything to build a Bradley Aerobat [vortechonline.com] (very similar to a Teenie Two,) for less than $20,000, and since you build it yourself, you are qualified as your own mechanic. There are/were some on eBay for less than $10,000, [ebay.com] but that is a non-turbo version.

Re:Skycar (1)

MobyDisk (75490) | more than 7 years ago | (#18523711)

You can buy a Used Cessna [aso.com] for well under $30,000 US dollars. Up your price to $40,000 and there are a lot more. A Hummer H3 runs between $30,000 and $40,000.

Re:Skycar (1)

zippthorne (748122) | more than 7 years ago | (#18523657)

Yes, but one reason is Moller's sticking to a flawed plan IMO. He states that he wants *everyone* to be able to have one, and he makes the appropriate design choice for that goal, but it's not an appropriate choice for a product that will be sold within even 10 years. He wants the plane to fly itself. (He also requires what amounts to a complete revamp of the ATC system, but NASA and others are already researching something similar to his needs in that arena)

As long as that's a requirement, the plane will never be ready. If he's willing to sell it as a toy for rich playboys with nothing better to do, it might one day take off, (heck, even if I had the money, I wouldn't buy the Fischer Price version anyway), but it doesn't look like he'll take the pragmatic route.

Re:Skycar (1)

shmlco (594907) | more than 7 years ago | (#18524813)

"As long as that's a requirement, the plane will never be ready."

Never be ready? I've been following the thing with interest for years, and as far as I know no one's ever seen the thing fly at all. Computerized or not.

Re:Skycar (1)

zippthorne (748122) | more than 7 years ago | (#18524873)

He claims tethered flight of the M200, (or an alleged M400 that looks suspiciously like a M200 to me...)

I don't know about the concept: a flying wing four feet wide, eight feet long, and only 400 mph seems a bit ambitious to me, but if the math supports it...

Though working model in hover mode seems more plausible to me.

I did not mean to imply that it was finished except for the control system. Although it does seem to me that the control system is significantly holding it back.

Re:Skycar (2, Insightful)

onescomplement (998675) | more than 7 years ago | (#18524057)

If I were their director of marketing:

"The Skycar remains perfectly positioned for the expected invention of antigravity."

Those Damn horseless carriages! (1)

ethicalBob (1023525) | more than 7 years ago | (#18524419)

Yeah, and those "horseless carriages" will never happen either! Communicating over WIRES? unHEARD of!

Unmanned, most likely (1)

stratjakt (596332) | more than 7 years ago | (#18523147)

I know fuel cells don't make a whole lot of power, ie; you're unlikely to ever see them power big rigs.

Anyone got any good data on the power they do make?

Re:Unmanned, most likely (1)

Timbotronic (717458) | more than 7 years ago | (#18523837)

TFA doesn't mention the power of the fuel cell but it does say it's not sufficient for takeoff and climb - just maintaining cruise. In order to climb, the motor needs additional power from a Li-Ion battery pack. I figure there'd be some potential safety issues with that. If you used up all your "climb power" you'd essentially have to rely on a glide approach for landing or maintain cruise until the fuel cell could recharge the battery enough for a "go round".

It'd be good to know what kind of power delivery would be required to eliminate the battery completely. I guess weight is the major obstacle at the moment.

Re:Unmanned, most likely (2, Interesting)

jdray (645332) | more than 7 years ago | (#18524593)

I guess weight is the major obstacle at the moment.

It is. Current (pardon the pun) PEM fuel cell technology typically uses platinum, AFAIK. Stacks are heavy. The Ballard Mark 1030 [ballard.com] provides about 78 Watts per liter of unit volume and 66 Watts per kilogram. The Ballard Mark 902 [ballard.com] , which is used in several fuel cell cars and buses, is much more powerful at 1133 Watts per liter of unit volume and 885 Watts per kilogram, but it's heavy (96 kilos, over 211 pounds). Note that neither of these devices weights include the power conditioning and management systems, fuel handling, etc. The entire integrated stack is much heavier when you're considering a "hydrogen in, electricity out" system. Furthermore, if you're not supplying fuel from a bottle of anhydrous hydrogen (a strange phrase if I've ever heard one), you've got a fuel reformer to take into account, which is one more package of weight and one more power draw on the system.

Having said all that, I think this is a great idea and hope it succeeds. From what I know (or think I know), so-called "ultracapacitors" are much lighter and more responsive than Lithium Ion batteries, and other slow-and-steady power generation systems, such as zinc-air batteries, might be able to back them up with better success.

Sony (0, Offtopic)

Anonymous III (1052122) | more than 7 years ago | (#18523177)

Cool as long as Sony aint involved, Hehe BOOM!

Skycar (1)

BigHungryJoe (737554) | more than 7 years ago | (#18523219)

Has anyone ever seen a Moller Skycar in operation anywhere? Outside of air shows and conventions?

Re:Skycar (1)

WED Fan (911325) | more than 7 years ago | (#18523471)

Have you ever noticed that you never see David Copperfield in the same place as the creator of the Moller Skycar?

The guy is either one of the most deluded inventors, financially incompetent, or a huckster. Or, all of the above.

Re:Skycar (1)

maxume (22995) | more than 7 years ago | (#18523875)

It's important to point out that you have never seen me in the same place as David Copperfield either.

Re:Skycar (0)

Anonymous Coward | more than 7 years ago | (#18524659)

Are you implying that you invented the Moller Skycar?

Ratios (1)

El Torico (732160) | more than 7 years ago | (#18523261)

Are the power to weight ratios comparable to current internal combustion engines? If so, great! If not, what about fuel cell powered dirigibles?

ha ha (3, Informative)

Quadraginta (902985) | more than 7 years ago | (#18523683)

Are the power to weight ratios comparable to current internal combustion engines?

You probably mean the external combustion engine, also known as the jet engine. Only small airplanes use pistons and such. And the answer is: of course not. This is yet another PR stunt aimed at the Gasoline Is Eeeeeeevil ninnies of the world who failed freshman chemistry.

If not, what about fuel cell powered dirigibles?

I don't think the problem with dirigibles is how to power them. I think the problem is that there's just about zero demand for a transport service that's about as slow as a ship or train but neither as efficient nor as reliable.

A big cargo ship carrying 70,000 tons of cargo can cruise at 15 knots with its 50,000 HP engines running at 80%. The EPA helpfully estimates [epa.gov] big marine engine fuel consumption as about 250 grams per kilowatt-hour, which lets you work out that a cargo ship consumes about 4 grams of fuel per ton of cargo per kilometer traveled.

Four locomotives pulling a hundred-car freight train at 60-80 MPH, with each car carrying 100 tons of cargo, will burn about 7.5 gallons [bts.gov] each per mile. That works out to 7 grams of fuel per ton of cargo per kilometer traveled.

There's no way any vehicle that flies can ever come close to that kind of fuel efficiency. So who would want cargo delivery that's just as slow, but much more expensive?

Re:ha ha (1)

modecx (130548) | more than 7 years ago | (#18523779)

You probably mean the external combustion engine, also known as the jet engine. Only small airplanes use pistons and such. And the answer is: of course not. This is yet another PR stunt aimed at the Gasoline Is Eeeeeeevil ninnies of the world who failed freshman chemistry.

In what way, exactly, is a jet engine not an internal combustion engine?

Sounds like someone failed basic understanding-of-how-things-work class. Grandma, is that you? I thought I told you stop trolling slashdot, damnit!

time to educate the masses again... (4, Funny)

Quadraginta (902985) | more than 7 years ago | (#18523817)

Go here [wikipedia.org] and look at the nice picture on the right-hand side. Notice that the combustion takes place in the exhaust stream, heading out of the engine. Not inside a cylinder.

Sounds like someone failed basic understanding-of-how-things-work class.

Oh I agree, definitely.

Re:time to educate the masses again... (3, Informative)

Captain Nitpick (16515) | more than 7 years ago | (#18523931)

Go here [wikipedia.org] and look at the nice picture on the right-hand side. Notice that the combustion takes place in the exhaust stream, heading out of the engine. Not inside a cylinder.

Sounds like someone failed basic understanding-of-how-things-work class.

Oh I agree, definitely.

Somebody failed looking at pictures class. The combustion chamber in a jet engine is quite definitely in the middle of the engine. Combustion takes place inside the engine, between the compressor and the turbine.

Not all ICEs have pistons, nor are all piston engines ICEs.

Re:time to educate the masses again... (1)

modecx (130548) | more than 7 years ago | (#18524469)

Notice that the combustion takes place in the exhaust stream, heading out of the engine.

Oh, so you mean jet engines are continuous flow internal combustion engines?

here's a clue, boy'o: which fluid is the working fluid in an internal combustion engine?

Answer(ROT13): Gur bar jurer pbzohfgvba gnxrf cynpr, qhzzl!

Re:time to educate the masses again... (1)

Nasarius (593729) | more than 7 years ago | (#18524753)

Wow, arrogant and stupid.

jet engine
any of a class of internal-combustion engines that propel aircraft by means of the rearward discharge of a jet of fluid, usually hot exhaust gases generated by burning fuel with air drawn in from the atmosphere.
http://search.eb.com/eb/article-9106039 [eb.com]

You fail it.

Re:ha ha (1)

acramon1 (226153) | more than 7 years ago | (#18524309)

There's no way any vehicle that flies can ever come close to that kind of fuel efficiency. So who would want cargo delivery that's just as slow, but much more expensive?
How about people who need to deliver cargo over terrain lacking waterways and railroads?

The nice thing about flight is that it doesn't require as much infrastructure. As long as there's a place to take-off and land (which, granted, may not be there), flight is a viable, and sometimes cost-effective, method.

Re:ha ha (1)

khallow (566160) | more than 7 years ago | (#18525309)

Wikipedia claims the Hindenburg could reach 135 km per hour, which is comparable with modern cargo trains at full speed and substantially faster than cargo ships. I imagine a modern version could go quite fast compared to the above transportation modes. So it appears to me that there is a niche there that isn't covered by current shipping modes.

More kinetic energy is bad (1)

dsanfte (443781) | more than 7 years ago | (#18523291)

Unless we're looking at some kind of computer-only piloting, a personal "skycar" would be a very bad idea. That's way too much kinetic energy in the hands of John Q. Public. You think car accidents are bad now? Wait for a midair collision that takes out a whole apartment block.

Re:More kinetic energy is bad (2, Interesting)

retro128 (318602) | more than 7 years ago | (#18523339)

That's way too much kinetic energy in the hands of John Q. Public.

I believe that's what they said about the automobile 100 years ago.

Re:More kinetic energy is bad (4, Insightful)

Loke the Dog (1054294) | more than 7 years ago | (#18523415)

And automobile accidents is actually a big deal today, so I guess they were right too.

Re:More kinetic energy is bad (0)

Anonymous Coward | more than 7 years ago | (#18523617)

a 2000lb aircraft isn't taking out an apartment block anymore than a 2000lb truck would.

I would go so far as to say that most of the kenetic energy in a midair is lost before the aircraft hit the ground. It would depend on how the aircraft come into contact. Usually the 2 airframes become tangled, and they fall straight down.

Re:More kinetic energy is bad (2, Informative)

dsanfte (443781) | more than 7 years ago | (#18523713)

That 2000lb aircraft is going to have two or three times the horizontal velocity of that truck, and an additional vertical velocity component when it impacts the ground.

Given the relation p = m v, you do the math on that, and couple it with the fact that no non-military building I know of is built to withstand impacts from above. Anyone in a home or apartment that's hit by a falling, fast-moving aircraft is dead meat.

Re:More kinetic energy is bad (2, Insightful)

mgv (198488) | more than 7 years ago | (#18523939)

And automobile accidents is actually a big deal today, so I guess they were right too.

Considering that 3000 people die per day from car accidents around the world, what we have is a disaster of the proportion of september 11, done daily.

Generally speaking, most countries seek to blame the individual driver. Most airlines seek to fix the system. And when you look at what they have had to do to make planes safe, its pretty clear that few of us really have a right to lift a few tons of metal into the air over any place that people are.

The real question that society needs to ask is how much it can justify letting so many people drive cars right now.

Just some food for thought. Wont really matter too much anyway, the oil will probably get too expensive before many people can afford this sort of technology. We will need what is left to fly the efficient, big planes.

And no, I would be bitterly opposed to people having flying cars, even if the technology made it possible.

My 2c

Michael

Re:More kinetic energy is bad (1, Interesting)

QuantumG (50515) | more than 7 years ago | (#18524401)

Maybe, just maybe, 3000 dying a day is acceptable because of the massive public good of swift personal transportation. But you're probably one of those people who thinks nothing can justify accidental deaths, let alone willful killing.

Re:More kinetic energy is bad (1)

macshit (157376) | more than 7 years ago | (#18524697)

Maybe, just maybe, 3000 dying a day is acceptable because of the massive public good of swift personal transportation.

Well the thing is that "swift personal transportation" as embodied by current automobiles really isn't much of a "public good" in many cases. Automobiles are well suited to sparsely populated rural environments, and very poorly suited to densely populated urban ones. The fact that they nonetheless are the standard transportation method in many large US cities is largely due to lack of forethought, blind herd instinct, and the power of fashion. I'm not sure those things are worth many deaths...

Re:More kinetic energy is bad (1)

mgv (198488) | more than 7 years ago | (#18524829)

Maybe, just maybe, 3000 dying a day is acceptable because of the massive public good of swift personal transportation. But you're probably one of those people who thinks nothing can justify accidental deaths, let alone willful killing.

Before you make too many assumptions about me, let me reflect this back on you:

Do you think that the mass good of air travel justifies the occasional deaths of 3000 people when a few planes fly into buildings?

If that isn't acceptable, then why should this occuring on a daily basis be ok with cars?

Anyway, before you assume that this means that I hate motor cars:

My wife and I share a car. Its a wagon. I ride a bicycle to work most days. The wagon lets me throw my bicycle into the car easily when it rains or whatever.

I love being able to drive places and the freedom that this brings. However, when you look at the carnage that cars produce, I find it impossible to say that this level of death is justifiable.

Now there are two solutions to this problem, and one of them is to stop driving. The other is to look at the whole system of driving. Just like the aeroplane industry did 20-30 years ago, when planes killed alot more people than they do now. I'm really glad that action was taken back then, it produces the safety that we have today. We have done this to a great degree with cars also, but have not gone anywhere near the safety levels of flight. Much more needs to be done. To oppose this is to say that its ok to have thousands of people die daily because you can't be bothered to fix the problem.

When thousands of people die from other causes, it gets much more interest.

So, yes, I like cars, at least in theory.

In practice they are killing alot of people, and consuming huge amounts of non-renewable resources to keep them running. At least the latter is probably fixable, and I look forward to the day I can buy a true electric car. The former is a really hard problem, but to ignore it is also crazy.

Does that put my position in perspective?

Michael

Re:More kinetic energy is bad (1, Interesting)

QuantumG (50515) | more than 7 years ago | (#18524863)

Yes.. in fact, I think it takes a lot more than 3000 deaths to justify the insanity that we have to go through whenever we want to fly. I think the grand total number of deaths due to flying is woefully inadequate to justify the massive concern for "safety" that the airlines are required to exhibit. I think that flying would be more routine and a hell of a lot cheaper if it was more dangerous and people would willingly pay for such a service if only their governments would butt out.

Re:More kinetic energy is bad (1)

mgv (198488) | more than 7 years ago | (#18525271)


Yes.. in fact, I think it takes a lot more than 3000 deaths to justify the insanity that we have to go through whenever we want to fly. I think the grand total number of deaths due to flying is woefully inadequate to justify the massive concern for "safety" that the airlines are required to exhibit. I think that flying would be more routine and a hell of a lot cheaper if it was more dangerous and people would willingly pay for such a service if only their governments would butt out.


Well, at least you are consistent.

Call me when a car (or plane) injures you or kills a family member, and explain to me then why you think its ok for your family members to suffer because someone else wanted a cheap air ticket or joy ride.

Personal freedom is fine, until (for example) I want the personal freedom to injure you.

Unless you think that is ok too...

Michael

Probably just feeding the trolls here now.

Re:More kinetic energy is bad (1)

QuantumG (50515) | more than 7 years ago | (#18525327)

People know the risks of living in the modern world. If they can't hack it, go live in the freakin' woods or something.

Making emotional arguments like that really doesn't befriend you to a geek audience.

Re:More kinetic energy is bad (1)

TooMuchToDo (882796) | more than 7 years ago | (#18525485)

Hey there chief, you are aware a private pilot's license only requires 40 hours of in-flight time, correct? I myself am training for my private license, have 12 hours of flight time, and have already solo'd (flying minus the instructor). General aviation has an accident rate of about 1 fatality per 100,000 flight hours (much safer then driving) although I agree that the barrier to fly is much higher then driving (which helps the accident rate).

Re:More kinetic energy is bad (1)

mgv (198488) | more than 7 years ago | (#18525865)

Hey there chief, you are aware a private pilot's license only requires 40 hours of in-flight time, correct? I myself am training for my private license, have 12 hours of flight time, and have already solo'd (flying minus the instructor). General aviation has an accident rate of about 1 fatality per 100,000 flight hours (much safer then driving) although I agree that the barrier to fly is much higher then driving (which helps the accident rate).

Of course, if everyone was flying around up there, there would be alot more collisions...

I'm pretty sure its more than 40 hours in Australia...

But I'd generally agree with you - flying is safer than driving.

Its the damage to society that cars do that troubles me - I've seen too much road carnage to ignore the down side of driving. Too many people in wheelchairs, or having lost limbs, or had their brains injured. Or worse.

Much less problems with flying, other than how to keep planes in the air as fossil fuels run low...

Michael

Re:More kinetic energy is bad (0)

QuantumG (50515) | more than 7 years ago | (#18523569)

Here's an idea, how about you making decisions about what you want to buy and leave me to make decisions about what I want to buy.

Re:More kinetic energy is bad (1, Interesting)

Anonymous Coward | more than 7 years ago | (#18525705)

> Here's an idea, how about you making decisions about what you want to buy and leave me to make decisions about what I want to buy.

When the thing you wish to buy can endanger public safety and security it is the community who decides. Your freedom does not cover the right to hurt others' freedoms and security (e.g. their right to live). If the aircar proses a real accident or terror hazard than the govt has right to ban it outright or mandate stringent skills and allegiance tests for drivers.

Just like the gov't can and does ban full-auto weapon trade from citizens due to massive destructive power, there can be limit on the kind of aircars available to laymen.

Re:More kinetic energy is bad (1)

stratjakt (596332) | more than 7 years ago | (#18523815)

How would two of todays light aircraft colliding take out a whole apartment block?

kinetic energy.. heh, your science teacher getting to physics?

Besides computers do all the flying these days.

Re:More kinetic energy is bad (1)

Asmandeus (640419) | more than 7 years ago | (#18523879)

Yeah... ever since I was young and heard the promises (and lies!) of near future sky cars I thought to myself that it'll never work until our buildings are made of something way harder and durable enough to withstand everyday "wear" of average people flying around.

I can just imagine people escalating the occasional "car drives into house" by entering through the roof.

Re:More kinetic energy is bad (0)

Anonymous Coward | more than 7 years ago | (#18524535)

Wait for a midair collision that takes out a whole apartment block.
You mean like that idiot of a baseball player who crashed his high-performance small airplane into a New York apartment building and did nothing but start a small fire and get himself killed?

Light airplanes are marginally more dangerous than automobiles for the occupants. For everyone else, they are unequivocally safer by a large margin. There's no reason to expect a "skycar" to be different, except to become even safer for the occupants as well in order to survive product liability litigation.

Reliability? (4, Interesting)

mcrbids (148650) | more than 7 years ago | (#18523333)

One of the biggest problems with smaller aircraft is reliability. Simply put, piston engines are not as reliable as jet engines. They must be rebuilt every 2,000 hours of flight under the best circumstances. And, with smaller planes at slower speeds, jets just don't make sense.

Turboprop engines are a good middle ground for mid-sized planes starting at the 12-seat size or so, but are very expensive for the smallest aircraft. (2 and 4 seaters)

Electric motors, other the other hand, can be incredibly reliable. If designed for it, they have just a single moving part, and can run continuously, 24x7x365 for many years without issues. This kind of reliability in a small plane would be just incredible!

Re:Reliability? (1)

YrWrstNtmr (564987) | more than 7 years ago | (#18523559)

This kind of reliability in a small plane would be just incredible!

Just as with cars, power density is the sticking point. And even more than cars, weight is an issue. Taking the standard Cessna 172:
Fuel capacity of 42 USG.
Range 790 miles.

Assuming the gas and electric engines weigh the same, and assuming 6lb per gal for Avgas....can we build a battery pack good enough for 790 mile range, with NO loss of power over that range, that weighs 250lbs?
(The Prius battery pack weighs about 1/2 that - 45kg))

Re:Reliability? (3, Interesting)

ppanon (16583) | more than 7 years ago | (#18523957)

can we build a battery pack good enough for 790 mile range, with NO loss of power over that range, that weighs 250lbs?

No, but that may be why they're looking at fuel cells which have different performance characteristics than battery packs.

My guess is that they really want to use it for military/police UAVs where getting rid of the noise from a combustion engine will seriously improve stealth operation modes. Smaller surveillance-oriented versions could perhaps be dropped from a mother ship and have smaller range requirements than you indicate.

Re:Reliability? (2, Informative)

CustomDesigned (250089) | more than 7 years ago | (#18523625)

The Moller Skycar uses rotary (Wankel) engines. One main moving part (rotor) each. It uses 8 of them, 2 in each of 4 rotating pods. It can lose at least 3 engines and still maintain stable flight (after that it depends on which you lose). There is also a parachute for the entire vehicle as a last resort.

The Wankel engines are much smaller and lighter for the same horsepower than piston engines. Their drawback for automobiles is similar to turbines - they don't like low RPMS (the rotor seals leak at low RPMS causing wasted fuel, seal wear, and pollution). This is not a drawback for aviation.

Of course, this design requires fly by wire computer control for everything, and you don't want your computer to fail (although the parachute could be manually deployed).

Re:Reliability? (0)

Anonymous Coward | more than 7 years ago | (#18524587)

The Moller Skycar uses rotary (Wankel) engines. One main moving part (rotor) each. It uses 8 of them, 2 in each of 4 rotating pods. It can lose at least 3 engines and still maintain stable flight (after that it depends on which you lose).
As far as I am aware, the Moller Skycar has never demonstrated any kind of untethered flight at all, much less stable flight, and certainly not stable flight with three engines out. How can you possibly claim that this machine can maintain stable flight under these extreme conditions when there is nothing remotely resembling proof?

Re:Reliability? (0)

Anonymous Coward | more than 7 years ago | (#18524331)

Reliabilty is not really a problem with piston engines. I own and fly a C182. I routinely get 2000 hours between overhauls. In fact my last time around I got 2400 hours before oil analysis showed traces of bearing material. Since I cruise at 160 MPH, that's 384,000 miles between overhauls. You would be hard pressed to find an automobile that gets that kind of mileage without major engine work.

Even turbine based engines such as the PT6-60A's on our King Air's rarely go 3000 hours. Those extra 1000 hours you get on a turbine, come at a great cost. Our last PT6 overhaul cost a shade over $325k. By comparison, I paid about 18k for my last overhaul.

Re:Reliability? (1)

mcrbids (148650) | more than 7 years ago | (#18525243)

Compare that to 43,800 hours that you could easily get with an electric motor with the capacity to run for just 5 years 24x7.

Yeah, you're happy. But airplanes are too expensive to be available to the common man. Few people have the $18,000 to rebuild your 182, let alone the $325,000 to rebuild your King Air. Result? Your beloved 182 costs something like 5x the cost per hour to operate as an average car, and has a safety record that's considerably worse. Statistically, single-engine piston planes are somewhere between a car and a motorcycle in safety per hour, somewhat closer to a car in safety per mile of travel due to the higher travel speed.

Anything that improves this mediocre record is a good thing.

Full Disclosure: I'm a solo pilot due to take my checkride sometime before the end of April, according to my CFI. I love flying, and am trying to figure out how to make it make financial sense as the father of 6 kids despite my 6-figure income.

Bah. (5, Funny)

rackhamh (217889) | more than 7 years ago | (#18523343)

Their heads are in the clouds on this one. This project will never fly. I bet it stalls and they never get it off the ground. It simply flies in the face of reason. That said, the sky's the limit when it comes to technological fantasy.

Re:Bah. (1)

Hektor_Troy (262592) | more than 7 years ago | (#18525807)

I bet it stalls and they never get it off the ground.
Technically if it stalls it's already off the ground. You might have meant that it stalls and crashes and burns.

Don't cross the road if you can't get out of the kitchen. And remember - a penny saved is worth two in the bush.

Blimps could be quiet (1)

Soong (7225) | more than 7 years ago | (#18523467)

But there just aren't good places to park all those cubic meters of helium each of our blimp-cars would need.

So, engine noise and laminar flow ducted fans? However you do it, flight needs a lot of power and it's going to get all that power to be smooth and quiet.

Use a compressor (1)

CustomDesigned (250089) | more than 7 years ago | (#18523565)

But there just aren't good places to park all those cubic meters of helium each of our blimp-cars would need.

Pump the helium (or hydrogen - that wasn't what started the fire on the Hindenber, although it certainly made it worse once it ignited) into tanks to descend. Release it into the gas bag to ascend. Pump it all into your tanks and fold up your envelope to park. Submarines do something like this with air.

Re:Use a compressor (1)

stratjakt (596332) | more than 7 years ago | (#18523777)

Dont you watch mythbusters?

It was the helium. It was not painted with thermite.

Re:Use a compressor (2, Informative)

Miseph (979059) | more than 7 years ago | (#18523947)

You mean hydrogen... helium is incredibly stable and does not combust at any temperature we would consider to be "normal" outside of a dying star.

Re:Use a compressor (0)

Anonymous Coward | more than 7 years ago | (#18525029)

I very much doubt that the helium burned.

Re:Blimps could be quiet (1)

maxume (22995) | more than 7 years ago | (#18523673)

We just need a way to hide stuff from gravity. If you could generate the force, you could probably hide a mass the size of a car with a nine volt battery.

You're a blimp, so stfu (0)

Anonymous Coward | more than 7 years ago | (#18524457)

we're talking about airplanes asshole

Ultralights (3, Interesting)

MobyDisk (75490) | more than 7 years ago | (#18523583)

I know nothing about engines, so can someone answer some basic questions for me? Wouldn't a fuel-cell engine be essentially an electric engine? Would it be quieter than a gasoline engine? More reliable? Would there be any odor? If so, they would be ideal for ultralights:

I am a hang glider pilot, and I would love to have a small engine for it. There are several manufacturers [doodlebugnorthwest.com] who make small engines [swedishaerosport.se] for them, they are loud, stinky, gasoline engines. Most of them only hold 1-2 gallons of fuel, which is plenty for this type of flight. Wouldn't a fuel-cell engine do the trick?

Re:Ultralights (1)

YrWrstNtmr (564987) | more than 7 years ago | (#18523917)

they are loud, stinky, gasoline engines.

An awful lot of that noise is the prop, not the actual engine.

Re:Ultralights (2, Insightful)

myrdos2 (989497) | more than 7 years ago | (#18524013)

Wouldn't a fuel-cell engine be essentially an electric engine?

-Yes, the fuel cell takes in hyrodgen and outputs electricity, which runs an electric motor.

Would it be quieter than a gasoline engine? More reliable?

Yes, and yes. Electric engines are virtually silent, and have far less moving parts than internal combustion engines.

Would there be any odor?

No, the only output from a fuel cell is water vapour.

If so, they would be ideal for ultralights:

Maybe! Your main problem here is fuel density. On the one hand, electric engines are around 95% efficient, compared to gasoline engines which are around 35% efficient. On the other hand, hydrogen isn't very dense - a liquid hydrogen tank requires roughly three times the volume of a gasoline tank with similar energy. (It also needs to be very well insulated) And by eyeballing the picture, it looks like they're using a compressed tank, not liquid. Probably one of those new 10,000 psi tanks, this being Boeing. Even at that pressure, the energy density's going to be a lot less than liquid hydrogen.

I note that they don't mention the range or price, which are going to be very small and very large, respectively. A fuel cell alone can set you back 30,000$ US. The cheapest I've seen for a complete system that can power a car is $60,000 US.

Re:Ultralights (1)

DayBoyUSA (626824) | more than 7 years ago | (#18524359)

All the fuel cells I have worked with run very quiet. The loudest noise is the fan bringing air into the unit and that is about as loud as some of the PCs I have used. The exhaust is pretty much air + CO2. I would imagine that fuel cells could provide significantly more power per weight than a battery. The fuel cell will provide electricity, so all you would need is an electric motor.

Re:Ultralights (1)

jdray (645332) | more than 7 years ago | (#18524677)

I think the important question is, "Given a (two stroke) gas engine and full (two gallon) fuel tank, what would the power of a fuel cell/electric motor system be for the same amount of runtime?" I think the answer is "Not much." Two stroke (noisy, stinky) gas engines are very good at converting fuel into mechanical power. You just pay for it in environmental damage, not only in noise and smell, but in toxicity.

Moller (1)

zippthorne (748122) | more than 7 years ago | (#18523605)

Heck, I'll be happy if we can get the regular version of mr. Moller's skycar.

It's not the engines which are noisy (5, Insightful)

M0b1u5 (569472) | more than 7 years ago | (#18523621)

It's not the engines which are noisy on Moller's ultra-dangerous thing (I refuse to dignify it with the title "car" or "aircraft" as it is neither) it's the fans/propellers which make all the noise. You simply can't move lots of air without making a hell of a racket.

See: Overclocked PCs, Helicopters, Jet Engine, extractor fan, air conditioner, Vacuum cleaner...

It wouldn't matter if Moller's thing had fuel cells - it would just as noisy.

Re:It's not the engines which are noisy (1)

DigiShaman (671371) | more than 7 years ago | (#18524423)

See: Overclocked PCs, Helicopters, Jet Engine, extractor fan, air conditioner, Vacuum cleaner...

None of these applications have blades that are acoustically optimized either with the exception of some CPU HS Fans and military copters.

I wouldn't put it out of the realm of possibility that the Moller's "thing" could be engineered to be more quite.

Re:It's not the engines which are noisy (3, Insightful)

M0b1u5 (569472) | more than 7 years ago | (#18524595)

Acoustic optimisation can onyl get you so far. In other words, you reduce fans/propellors from "an ear damaging roar" to simply "extremely fucking loud". There's only so much you can do to quieten fans;

You can get cute and use TMD (Tip Magnetic Drive) fan blades, which have no ends (its thought that tip vortex at the end of fan blades is responsible for much of the noise associated with fans and blades) and you could spend millions designing the most efficient blades possible.

Hell, you could even bet that in a few years the next generation of memetic polyalloys (T1000 et al) or "memory metals" will even allow the actual blades to change shape depending on their rotational speed, thus reducing noise still further.

But the fact remains, on a 2000 KG car, you need at least 2000 KG of vertical thrust to keep it in the air, and 2000 KG of thrust is a LOT. Are you seriously suggesting that fan blades can be made as quiet as say - a 5-litre V8 car at 6000 rpms? No way. Not gonna happen. Not ever.

Unless some way can be made to shift large amounts of air, efficiently, with no blades at all, then the Moller thing will never be anything more than a fucking dangerous, extremely noisy experimental demonstrator.

I'm still hanging out for effective anti-gravity. After all, it's such a weak force, that 2 AA batteries should be powerful enough to keep your car airborn for a year or so. Then all you need is some way to move it about, and you only need one engine for that - so it'd be much quieter.

Re:It's not the engines which are noisy (0)

Anonymous Coward | more than 7 years ago | (#18526095)

What about, erm, what are they called....cylons? Or whatever the term is; you know, those things on certain helicopters where the tailrotor is caged in. Apparently those make a LOT less noise.

Electric Aircraft (2, Interesting)

Sloppy (14984) | more than 7 years ago | (#18523927)

Huh. Haven't heard of that before. That's pretty unusual, no?

Re:Electric Aircraft (2, Interesting)

mjwx (966435) | more than 7 years ago | (#18524549)

Not so strange, after you find out about this [wikipedia.org]

Another Lightning Rod..... (2, Funny)

IHC Navistar (967161) | more than 7 years ago | (#18524227)

Soon, the complete idiots who build their homes next to airports and then complain about all the noise will have another thing to whine about.

Energy density is getting there. (2, Interesting)

Animats (122034) | more than 7 years ago | (#18524805)

Battery energy density is finally getting good enough for this sort of thing. Electric cars with real performance are at last possible, although the trunk full of laptop batteries still costs too much.

For aircraft, the price point is higher, so this could work. There are lots of little electric-powered unmanned aircraft around, from toys to small military recon units. An outfit called Aviation Tomorrow [archive.org] was making noise about an electric-powered kitplane back in 2002-2005. They got to the point where they'd announced the first flight test in 2005, then disappeared. What seems to have gone wrong is that they originally planned a battery powered plane, which would have worked, then switched to hydrogen and Ballard fuel cells, which didn't.

The embarrassing fact about the fuel cell industry is that almost nobody is shipping a usable product. It's still all prototypes. Five years ago, Ballard was about to launch a commercial product with Coleman, but they couldn't make it work well, and Coleman backed out. APC supposedly sells a fuel cell product for server backup power, but it doesn't really seem to be installed in any quantity. (For one thing, it requires chilled water for cooling, which is a real problem if you need power to chill the water.)

Re:Energy density is getting there. (0)

Anonymous Coward | more than 7 years ago | (#18526297)

"Electric cars with real performance are at last possible, although the trunk full of laptop batteries still costs too much."

Laptop batteries on cars are an extremely bad idea. Imagine this: you are driving along, minding your own business, some other car crashes into yours and you explode. Nice uh?

Lithium batteries are sensitive to heat and impact (which can cause a short-circuit, leading to heat), and can explode. If you've seen pictures of exploding laptop batteries, now imagine an explosion with 30 times as many battery cells. It's like some kind of personal Hiroshima.
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