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

With the civil air travel market under increasing pressure from rising oil prices and ecological legislation, the race is on to find practical options to conventional kerosene and these so far seem to come down to different kinds of biofuel.

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

Jatropha 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 pointed out Jatropha curcas as one of the very best prospects for future biodiesel production. It is resistant to dry spell and pests, and produces seeds including 27-40% oil.

Recently, US aerospace giant Boeing, Brazilian aerial major Embraer and the Sao Paulo state Research Support Foundation transferred to bring out research and development into making use of biofuels to power jet airliners. It was reported that Brazilian airline companies Azul, Gol, TAM and Trip would act as strategic experts for the project.

The latest airline to start experimenting with new fuels is the Alaska Air Group which has conducted internal US flights utilizing a blend of 80 % petroleum based fuel and 20% biofuel made from cooking oil. This mixture, it is claimed, can cut damaging emissions by 10%.

One really encouraging advancement has actually been the relocation far from biofuels which complete head on with food consumers thereby avoiding a rate spiral. Not so long ago, a surge in use of biofuels in automobiles caused a spike in maize rates as US farmers diverted too much corn to fuel processing.

Hopefully in the future, airline companies and motorists will focus biofuel consumption on non-food sources such as jatropha and algae. It would be a blended true blessing certainly if some individuals ended up to please another person's green qualifications.