The test, scheduled for the third quarter of this year, is likely to involve a trans-Pacific trip, far longer than the one-hour test flight that was conducted in China last October, said Stephen Emmert, Boeing's regional director of the biofuel strategy team for China and North America.

The project aims to prove that a China-produced biofuel works, and to ensure "regulators and airlines around the world are comfortable using it for commercial flights," he said.

The planned test, like last year's, will involve use of a biofuel produced by PetroChina (601857.SS) from locally grown jatropha, a thorny green shrub. Jatropha based fuel, produced with oil extracted from seeds, could have particular appeal in China, where there are huge swathes of barren land that could be turned to growing the plant.

"China has a need (for cleaner fuels) like the rest of the world that is very real," said Marc Allen, head of Boeing's (BA.N) China operations, speaking on the sidelines of the International Air Transport Association meeting in Beijing this week.

"They have (economic) scale that many parts of the world cannot match. And they have fast growing technological capability that will allow them to be on the forefront on these initiatives."

(Reporting By Beijing Newsroom; Editing by Daniel Magnowski)

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