It's bad enough for some propeller airplanes to be referred to as being powered by rubber bands. Now the cynics could start having a dig at industrial airplane flying on whatever from cooking oil to melted algae.

With the civil air travel industry under increasing pressure from increasing oil rates and legislation, the race is on to find practical alternatives to standard kerosene and these so far appear to come down to various types of biofuel.

Not surprisingly, the first trials of alternative fuel were started by British air travel leader, Sir Richard Branson, whose Virgin Atlantic began London to Amsterdam flights with minimal biofuel usage in 2008. This was quickly followed by Lufthansa and Air New Zealand who each used different blends of routine fuel and bio derivatives including some from made from jatropha curcas which can grow in soil considered too bad for growing mainstream foodstuffs.

jatropha curcas is a genus of roughly 175 succulent plants, shrubs and trees (some are deciduous, like Jatropha curcas), from the household Euphorbiaceae.

In 2007 Goldman Sachs cited Jatropha jatropha curcas as one of the very best candidates for future biodiesel production. It is resistant to drought and bugs, and produces seeds containing 27-40% oil.

Recently, US aerospace giant Boeing, Brazilian aerial significant Embraer and the Sao Paulo state Research Support Foundation moved to perform research study and advancement into using biofuels to power jet airliners. It was reported that Brazilian airline companies Azul, Gol, TAM and Trip would act as tactical experts for the job.

The current airline company to start experimenting with new fuels is the Alaska Air Group which has conducted internal US flights using a mix of 80 % petroleum based fuel and 20% biofuel made from cooking oil. This mix, it is declared, can cut harmful emissions by 10%.

One really motivating advancement has actually been the relocation far from biofuels which compete head on with food consumers thereby preventing a cost spiral. Not so long earlier, a rise in usage of biofuels in automobiles caused a spike in maize prices as US farmers diverted too much corn to fuel processing.

Hopefully in the future, airlines and vehicle drivers will focus biofuel intake on non-food sources such as jatropha and algae. It would be a mixed blessing indeed if some people wound up starving just to please somebody else's green qualifications.