It has been widely reported that China has been ramping up efforts to develop its new-energy car industry. Now, new-energy planes are also on the horizon.

The Lingque H, a new-energy plane designed by the Commercial Aircraft Corp of China (COMAC), has completed another test flight on March 10, taking off from an airport in Zhengzhou, capital of Central China's Henan Province, according to an article posted on COMAC's official public WeChat account on Monday.

The Lingque H had "a steady flight," with the aircraft systems responding well, which provides sufficient verification of the hydrogen fuel cell systems it uses, COMAC said.

The company did not supply full details of the flight such as the flight length. The plane has a wing span of 6 meters, it said.

The Lingque H has made a number of test flights since January 2019, which signals that COMAC's future civil aircraft program has made "solid progress" in its exploration of the new-energy area, the company noted.

The aircraft uses hydrogen fuel cell hybrid power technologies, to verify the feasibility of using such a system on aircraft. It mainly uses hydrogen fuel cells, supplemented by lithium batteries. A number of advanced technologies such as 3D printing were used.

Song Zhongping, a Chinese military expert and commentator, said that the test flight signifies the completion of the experimental stage. Now the plane needs to go through the engineering verification stage and the practical application stage.

"Generally speaking, after the experimental stage, companies would make an 'engineering prototype' that's exactly the same size as the planes that will be put into production. Only when the test flight of that engineering prototype is successful can the planes be ready for actual use," Song said.

According to Song, only some of the new-energy plane technologies have been verified so far. There are still many technological hurdles and much technical verification needs to be done before the concepts can become reality. "It will be a very long path," said Lin Boqiang, a professor at Xiamen University.

"It's unlikely to happen unless the government invests a large sum of money to support the relevant research," he told the Global Times on Tuesday.

But despite the hurdles, new-energy planes will be an important development direction for China, according to Song. "For one thing, new-energy batteries don't produce noises like traditional turbine engines and turboshaft engines do. For another thing, new-energy batteries do not pollute the environment while jet fuel produces serious atmospheric pollution."

More importantly, as hydrogen is ample, the price of hydrogen cells will be much cheaper than traditional fuel in the long run, which will largely reduce the cost of new-energy planes. That's based on the premise that hydrogen technologies become mature with continuing research and development (R&D), Song said.

"So far, the cost of hydrogen cells is still relatively high because we are still in the expensive R&D stage, but costs will fall significantly. The time when China can put new-energy planes into practical use mostly depends upon the R&D pace of new-energy fuel cells," he said.

In the recently released Government Work Report, the government announced that it would push the construction of hydrogenation settings, the first time that hydrogen technology appeared in the report.