hotshot

Does anyone know if it's possible and/or legal to run a diesel powered aircraft on biodiesel or veggie oil? I know it's possible to run a diesel truck on French fry grease, so I don't see why it would be a problem in a diesel powered airplane. Also, is diesel capitalized?

jsfBoat

I read a few articles a while back about some GA aircraft that were dieseled powered being converted to use biodiesel. Heard it produces the same power as diesel, but with out the greenhouse gases produced as a byproduct.

zondaracer

"In aircraft applications, biodiesel is used as a blend, rather than 100%. This is necessary in order to reduce the effects of biodiesel's low temperature crystallization and thickening. If you were in an airplane at 20,000 feet, where the temperature is possibly well below freezing, and your fuel thickens to the point where it can't be pumped to the engine, that's a very bad situation." I found that on another website.

I think in the future, biodiesel would have to have an aviation grade developed in order to run on 100% biodiesel. I guess piston driven aircraft normally wouldn't fly to such high altitudes and it is less of a concern than a high altitude aircraft. I actually read somewhere that to create a bio jetfuel, a blend of biodiesel and ethanol would create the cold temperature properties similar to jet-a

MoosePileit

There's an L-29 Delfin out of Las Vegas running Biodiesel of some blend and testing it out- catch it at OshKosh:

http://www.airventure.org/2008/news/080313_biojet.html

rickair7777

Turbine airplanes should be able to run on bio-diesel, and I would guess that you could just fill one up and go fly with no special modifications.

However...

It would probably freeze solid at lower temps.

It is NOT equivalent to petroleum based kerosene for specific energy...it provides about 30% less energy, so it would significantly reduce the range.

It is pretty green as far as "traditional" pollutants go (sulfer, hydrocarbons), but I think it makes MORE greenhouse gas (CO2).

If you're going to use artificially manufactured fuel, coal or natural gas derived fuels work much better (essentially identical to kerosene).

zondaracer

Even better would be to produce a specific biojetfuel that has properties similar to current kerosene jetfuel. That way you dont have the pitfalls associated with using biodiesel in place of jetfuel.
http://blog.wired.com/cars/2008/04/algae-farm-to-p.html

rickair7777

You could probably get most of the needed properties (such as feezing temp) through additives or adjusting molecular ratios.

However, the underlying chemisry of biofuels is simply different than petro fuels...methyl/ethyl molecules are more complex than the simpl-chain hydrocarbons in petroleum. This means less energy per volume and weight...especially by weight. You can fiddle with additives and ratios of the various molecules, but the stuff is still what it is...

Kind of like building a airplane made of lead instead of aluminum...you can alloy the lead to change it's properties some, but it still going too be way to heavy to fly. The only way around it is to not use the lead.

zondaracer

I just read this today, algae to gasoline, not ethanol, gasoline
http://news.cnet.com/8301-11128_3-9954638-54.html
They say it is chemically identical, now they need to make a jetfuel

hotshot

That's really neat. If that actually becomes a full scale reality, I want to see Exxon's CEO sh!t his pants.

And for the record, Aston Martins are better than Zondas.

Cubdriver

And I just read this today from the AIAA listserve:

JAL announces biofuel flight.

Reuters (6/23, Hayashi) reported, "Japan Airlines Corp (JAL) said on Monday it planned to fly Asia's first commercial jet flight powered by biofuel before next March, as part of an international drive to reduce CO2 emissions from aviation." The carrier "will use a Boeing 747 aircraft with engines made by Pratt & Whitney." If the flight occurs as planned, "JAL will be the first Asian carrier to make such a flight and the fourth worldwide after British airline Virgin Atlantic, Air New Zealand and Continental Airlines." According to Reuters, "details such as the source of the fuel and the route of the demonstration flight will be decided by August." It noted, however, that "Boeing has previously been looking at algae as a source of biofuel."

The AP (6/23) added that "JAL will use a biofuel mixed with kerosene in one of four engines on the jet, with the three remaining engines powered by ordinary jet fuel or kerosene." The company "said it plans to use a new generation of biofuel made of non-edible materials to avoid using potential food sources."

According to Aviation Week (6/23, Warwick, Norris), JAL "is the fifth airline to announce a biofuel demonstration." In addition to the previously mentioned airlines, "[l]ow-cost carrier JetBlue Airways...has partnered with Airbus, A320 engine supplier International Aero Engines and Honeywell process technology company UOP to develop and test sustainable biofuel, aiming for certification by 2013." JAL also announced that "high fuel prices are forcing it to close down its 747-400 flight training base at Moses Lake in Washington." The company "plans to begin phasing out passenger 747s in 2009," and will not fly cargo-oriented 747s "in sufficient numbers to warrant a special flight training section."

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