The fourth test aircraft of the C919, China’s first home-built narrow-body passenger jet, took part in a test flight in Shanghai on Thursday, China Daily reported.

The progress indicates that the C919 will speed up its work in getting airworthiness certification, an industry expert said. Another two new test jets, the 105 and 106, will complete their first test flights later this year, before entering the market in 2021.

Four C919 jets — the 101, 102, 103 and 104 — have completed testing, and now they are undergoing more intense test flights, static tests, and other ground tests at several testing bases, said Commercial Aircraft Corp. of China (COMAC), its manufacturer.

The C919’s latest test flight comes at a time when its competitor Boeing’s 737 MAX jets remain grounded worldwide following two fatal crashes that have been blamed on software issues that killed a total of 346 people.

In March, China was the first country to ground the aircraft from commercial flights. The Civil Aviation Administration of China has also suspended the airworthiness certificate application of the model for Chinese airlines, the report said.

Last week, Boeing reported a nearly US$3 billion loss for the second quarter, its worst loss ever for the US aircraft manufacturer. It delivered 104 fewer airplanes to customers compared to the same quarter last year.

Meanwhile, Boeing’s arch-rival Airbus posted stronger-than-expected second-quarter earnings. Its net profit reached US$2.2 billion, its earnings report said.

“As there is no timetable for the B737 MAX to resume flying, passengers have shown a falling confidence in the model, and the global market would more welcome its competitors. The MAX issue also reminds China that it is quite important to do one’s own work well and develop a safe aircraft,” said Lin Zhijie, an aviation industry analyst.

“Now there are still some gaps between the C919 and mainstream single-aisle aircraft of Boeing and Airbus in economic efficiency and other aspects. After the C919 enters commercial use, it will continue to upgrade and improve, and in the long term, it is likely to challenge major Western manufacturers,” he said.

According to AINonline sources, the C919 is still experiencing some technical design issues.

One of the long-standing impediments constraining progress is the integration of avionics components and its subsystems in the flight deck, the source said.

The C919 features a complete avionics system design with key components sourced from western suppliers.

Aviage Systems, a 50-50 joint venture between GE Aviation and Aviation Industry Corporation of China, supplies an integrated modular avionics system.

Honeywell Aerospace supplies the aircraft’s fly-by-wire system with HonFei flight controls as well as the braking system under a joint venture with Boyun Aviation Systems.

Collins Aerospace, under joint ventures established with China Electronics Technology Avionics Company and AVIC, supplies the C919’s communication, navigation and integrated surveillance systems.

Getting all these component teams on the same page, has not been an easy task, the source said, and simply throwing more money at the C919 will not make it globally competitive.

While foreign firms have contributed major components to the program, Chinese teams on the factory floor are tasked with system-wide integration, the source said.

Not only does this require highly coordinated teams, it also requires a fair degree of technical know-how to bring its ambitious C919 project in line with FAA and EASA requirements.

“If they are going to sell this aircraft outside of China, they will need FAA and EASA approval, and both are difficult to get,” said the source.

To make the aircraft truly “Western ready,” operating manuals also need to be in English and up to international standards.

“Mechanics, pilots,and other personnel supporting the aircraft delivery and operations also need to be taught in English. It is imperative to have a global support system that inspires confidence.”