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Interesting. I've never heard of such a thing. But wouldn't you need to replace a substantial part of the engine itself?

"Because hydrogen has a much lower energy density and burns much faster and hotter than gasoline, compression ratios can be increased, and more air is mixed with the fuel to keep combustion temperatures and exhaust emissions down. Most hydrogen engines run lean (air-to-fuel ratio of 30:1 or more)," - that's very non-standard for internal combustion engines isn't it? About twice normal? What effects would that have, i.e. would you have to rework all the sensors etc that control air intake and exhaust? It seems like you'd need an engine custom built for this, and you'd still need all the advances in storage/compression that fuel cells need as well.

I found a couple articles saying that the Wankel engine or a quasi-turbine engine is better performing for a hydrogen internal combustion engine than a piston design.

http://www.monito.com/wankel/hydrogen.html/

http://auto.howstuffworks.com/quasiturbine.htm/

Why would you have to hop them up? If anything, since you have redundant engines, you can reduce their power.

http://www.monito.com/wankel/aircraft.html

That page points out a wankel engine that runs on 10 liters per hour, or 2.6 gallons. Now, if that plane is going 200 miles an hour, that's 77 miles per gallon.

Get it?

Yep, norton had a rotary powered bike. These look like some cool bikes!

http://www.monito.com/wankel/norton.html

It's called a Wankel engine and is conventiently ignored by the majority of engineers because they remember the engine sealing problems with the early NSU Ro80 in the late 60's that almost bankrupted them.

Talk to most people about the Wankel engine and the chances are they've never heard of it. Many engineers laugh when you mention it, because they remember 1967 and haven't heard of all the developments since then. My old (1983) Mazda RX7 did 127000+ miles before the engine wore out.

The spiffy model on the showroom floor is nothing more than a stage prop. It doesn't fly, it never did, and it probably never will.

Unless the man is a bare-faced lier, you can find out all sorts of things about it at moller.com.

Need I remind you that VTOL aeroplanes have been built before (albeit with jet engines).

The question from the orginal conversation was "has anyone used a wenkel rotary (it has a low weight to power ratio) in a plane?" Why/Whynot . . .

They have.

OT: My '86 RX-7 is a blast to drive. I wish they still made them.

Doubtless you know that Norton produced Rotary Powerered Motorcycles several times. I've seen a couple small pictures of the older bikes, but I couldn't find anything likely just now.

First-generation RX-7's were actually carbureted, according to a mention here

Yeah? Well, I wonder what a wankel engine in one of those could do...

Really?

Never mind turbines, I'd rather be wankeling my hydrogen!

At the Detroit Autoshow Media Preview days, I had a chance to talk to an engineer from Mazda about hydrogen Rotaries (if you are unaware of Mazda H2 Rotaries, check out this website

They said the largest problem for them right now with hydrogen is delivery and distrobution. Mazda has the in-vehicle delivery system basically in place, and can, within a matter of months, crank out rotary powered hydrogen cars. "We are ready to go" he said, "If they distribution system was in place today, we'd be number one on the market.

Additionally, he said retrofitting older fuel injected rotaries (13b RX-7's from 1984 on) would only need the fuel tank replaced, injectors replaced, and computer repoogrammed.

The remaining problem: there is only 68k BTUs per ft3 for H2 compressed at 3500 psi. At the same ft3 for gas yeilds 922k BTUs. Increasing the PSI for in car storage is a major research focus for the auto industry right now... Hyundai has developed a 5000 psi tank, but that still falls short of the 922 BTU's that has has at 1 ft3

Here's a little more info if you weant to do some research.

Tom.