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

With the civil aviation industry under increasing pressure from increasing oil costs and environmental legislation, the race is on to find practical alternatives to traditional kerosene and these up until now appear to boil down to various kinds of biofuel.

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

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 pointed out Jatropha curcas as one of the finest candidates for future biodiesel production. It is resistant to drought 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 perform research and development into the use of biofuels to power jet airliners. It was reported that Brazilian airlines Azul, Gol, TAM and Trip would act as strategic specialists for the task.

The current airline to start exploring with new fuels is the Alaska Air Group which has carried out internal US flights utilizing a blend of 80 % petroleum based fuel and 20% biofuel made from cooking oil. This mix, it is claimed, can cut harmful emissions by 10%.

One really encouraging advancement has actually been the move away from biofuels which complete head on with food customers thereby avoiding a cost spiral. Not so long ago, a surge in usage of biofuels in vehicles triggered a spike in maize prices as US farmers diverted too much corn to fuel processing.

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