Air NZ's Biofuel Test Flight  

The Australian reports that Air New Zealand will soon trial a fuel mix using 50% biofuel from jatropha plants - Oil from wasteland tree to power Air NZ jet.

A BIOFUEL due to be used in a world-first Air New Zealand flight test next month may give aircraft an energy boost and reduce their environmental footprint.

Tests by engine-maker Rolls Royce show the 50/50 blend of Jet A1 and fuel converted from jatropha plant oil met or exceeded all critical criteria, including a freeze point of -47C and flash point of 38C. But it also has a higher energy content and lower specific gravity than the Jet A1 fuel available in most countries and the Jet A fuel airlines buy in the US.

Rolls-Royce, which tested the fuel at facilities in Britain, said the blend met or exceeded technical requirements for civil and military aircraft as well as the requirements of a "drop-in" fuel whose properties were virtually indistinguishable from conventional fuel. This means it can be put straight into today's jet engines without the need to make expensive modifications.

Air NZ chief pilot David Morgan said the ability to mix the biofuel with normal fuel was important because airlines may not be able to get the new type in all ports. He expected airlines to be able to use anything from 100 per cent biofuel to various levels of blends.

He also expected to see a reduced fuel burn per nautical mile because of the higher energy content in the new is fuel. He noted that Qantas and Air NZ flights buying the less energy-rich Jet A in the US loaded a 0.2 to 0.3 of a per cent extra because it had less calorific value. This meant, all things being equal, that airlines used more fuel coming out of the US than in travelling there. "So the high calorific value and low specific gravity is a win-win," he said.

Mr Morgan said the aviation industry consortium involved in the test had opted for a blend was because of the biofuel's lower specific gravity. "For the purpose of the test we need to bring it close to normal jet fuel specific gravity because one of the purposes of this test is to prove the efficacy and viability of biofuel in the normal system," he said.

Air NZ will test the blend in various operating conditions in one of the four RB211 on the 747 during a two-hour flight on December 3 and Mr Morgan doe not anticipate any surprises.