Boeing 737 Max airplanes sit parked at the company's production facility on November 18, 2020 in Renton, Washington. Photo: VCG

China's civil aviation regulator released an airworthiness directive on the grounded Boeing 737 MAX on Thursday, showing that the airplane has won support from the agency, a further step for the plane to return to flying in Chinese skies.

However, this does not mean the plane will return to service in China immediately, and it will take time for the modification of the aircraft by domestic airlines and pilot training, Chinese experts said. 

According to an airworthiness directive posted on the official website of the Civil Aviation Administration of China (CAAC), the authority has confirmed that the relevant corrective measures can eliminate the unsafe state of the Maneuvering Characteristics Augmentation System (MCAS) of the model, which means that the Boeing 737 MAX has no airworthiness regulatory obstacles now in the country. 

The announcement shows that the authority has given approval to the plane's comeback. After the corrective measures in the airworthiness directive are completed, the relevant aircraft are eligible to go back into service, Wang Yanan, chief editor of Beijing-based Aerospace Knowledge magazine, told the Global Times on Thursday. 

Last month, China's civil aviation regulator said in a request for public comment on airworthiness directives that in order to address unsafe conditions relating to the 737-8 aircraft MCAS within the 737 MAX family, Boeing initiated design changes to the flight control system software and display system software.

After a comprehensive assessment by the CAAC, it was confirmed that the relevant corrective measures can eliminate the above unsafe conditions.

China, the first country to ground the 737 MAX after two fatal accidents, has maintained that for the plane to resume commercial services, aircraft modifications must be approved for airworthiness, and pilots must be fully retrained to fly the model. The authority also demanded that the findings of investigations into the two fatal air tragedies must be made available and the defects, which caused the incidents, must be addressed.

Although there are no obstacles in the airworthiness permit, it will take some time for the 737 MAX to go back into service, and airlines need to carry out tasks such as aircraft modification and pilot training. 

The next step for Boeing will be modifying each grounded 737 MAX according to the sample it showed to the CAAC, and this will be done one plane at a time, and at one carrier at a time, no matter whether it involves hardware or software, Wang said. 

Boeing remains hopeful that the 737 MAX will return to service in China before the end of this year, but the ultimate decision is in the hands of the regulator, Richard Wynne, managing director of China marketing for Boeing Commercial Airplanes, told the Global Times in September.

There are 97 737-8 jets in China, and all of them are grounded. 

In November last year, the US Federal Aviation Administration announced that the Boeing 737 MAX had obtained a go-back to sky permit, and countries such as Brazil and Canada then followed suit.