Boeing Working on Fuel Cell Aircraft 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."
Reliability? (Score:5, Interesting)
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:More kinetic energy is bad (Score:3, Interesting)
I believe that's what they said about the automobile 100 years ago.
Re:Skycar (Score:2, Interesting)
Ultralights (Score:4, Interesting)
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?
giant rubber bands (Score:4, Interesting)
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.
Electric Aircraft (Score:3, Interesting)
Re:Reliability? (Score:4, Interesting)
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:More kinetic energy is bad (Score:2, Interesting)
Re:Electric Aircraft (Score:2, Interesting)
Re:Unmanned, most likely (Score:3, Interesting)
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.
Energy density is getting there. (Score:3, Interesting)
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:More kinetic energy is bad (Score:2, Interesting)
Re:More kinetic energy is bad (Score:1, Interesting)
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.